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Construction Research Congress 2005: Broadening Perspectives Proceedings of the Congress

April 5–7, 2005 San Diego, California

Editor(s): Iris D. Tommelein

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LEAN CONSTRUCTION JOB SHOPS

Select this Article		SLAM—A Case Study in Applying Lean to Job Shops Todd Brink and Glenn Ballard ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)1 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Lean production has been applied broadly within manufacturing, but mostly to production systems that can be structured as flow lines. Can lean be applied to production systems that produce small numbers of a wide variety of custom products and thus do not lend themselves to a flow line structure; i.e., to job shops? Systems structured as job shops belong at the same end of the spectrum of production system types as do projects, so finding how to take job shops lean could have important implications for both manufacturing job shops and the application of lean to project based production systems such as those producing capital facilities, developing consumer products, and engineering software. Spancrete, a Midwest fabricator of concrete products, is achieving great success with its lean implementation. The primary tool is value stream mapping, which is done by employee teams with participants drawn from every level in the organizational hierarchy. Substantial performance improvements have been made, but arguably the most important change is cultural, the transformation of Spancrete into a learning organization. This paper reports the methodology and the results Spancrete has achieved and suggests how their methodology might be applied by others.

Select this Article		Value Stream Mapping for Make‐to‐Order Products in a Job Shop Environment Thais da C. L. Alves, Iris D. Tommelein, and Glenn Ballard ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)2 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract This paper investigates the use of Value Stream Mapping (VSM) for make‐to‐order products in a job shop environment, specifically the fabrication of Heating Ventilating and Air Conditioning (HVAC) sheet metal ductwork. The use of VSM for analyzing the production of repetitive units has proven to be successful in different industries. The use of VSM for studying the production of non‐repetitive units requires some adaptation from repetitive‐unit uses in order to successfully capture the attributes of multiple product families required at different frequencies and volumes. The VSM for a job shop environment has to be flexible to deal with the dynamic nature of job shops, e.g., maps may change daily according to the products scheduled for fabrication. Other aspects of the production system for sheet metal ducts that should be captured in the maps include the availability of a multi‐skilled workforce for shop and site work, single flow of product and worker, and development of forecasts and capacity allocation to deal with frequent changes on incoming orders from project sites. Besides discussing the peculiarities of this job shop environment and their representation in a VSM, the authors discuss the process for elaborating VSMs for this production system and the definition of data used to develop them. Finally, the authors present a VSM for the fabrication of sheet metal ducts and discuss it using Lean Production concepts and recommend systematic data collection to reveal current practices and opportunities for improvement.

Select this Article		Analysis of Variability in Precasting and Installation of Pile Foundations Hasan Kaplan, Andries Elburg, and Iris D. Tommelein ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)3 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents a study on the use of pre‐stressed precast foundation piles using data collected on a building project that comprised the installation of more than 340 piles. The objective is to assess the presence of product and process variability in demand and supply, and the impact it has on precast pile delivery. Sources of variability in precasting, transportation, and installation are described. As a step towards understanding the complexity of this production system and to show how production planning decisions affect execution, this paper elaborates on two deterministic scenarios and compares those with actual data from the project. Performance of the system is analyzed on the basis of inventory vs. work completed. From the perspective of ‘lean’ thinking the paper then identifies sources of waste and suggests means to eliminate them. It also presents questions for follow‐on research.

Select this Article		Fabrication Lead Time and Demand Variability: An Empirical Study Chien‐Ho Ko and Glenn Ballard ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)4 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract This paper reports the methods and initial findings of an empirical study of fabrication lead time and demand variability conducted with a precast concrete fabricator. The study is the first step in an exploration how changes in design or required delivery of fabricated products impacts the fabricator's execution of a customer order; first the impact on on‐time delivery rates and the durations between execution milestones, then the impact on fabricator efficiency and costs. The study was performed on previously completed projects at the fabricator's largest plant. Averages and standard deviations were calculated for durations between the key milestones in execution of an order. Actual versus planned dates were compared for each milestone after project award, the on‐time delivery percentage calculated and the distribution of positive and negative values documented. Jobs were categorized by size, type and product mix. This study is preliminary to an evaluation of current projects, which will include documentation and analysis of changes in design information, delays in achieving final approval of erection (shop) drawings, and changes in required delivery date.

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LEAN SUPPLY AND PROJECT DELIVERY

Select this Article		Restructuring the Rebar Supply System Iris D. Tommelein and Glenn Ballard ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)5 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract The rebar supply system includes all the organizations involved in the manufacturing, design, procurement, fabrication, transport, installation, inspection and regulation of reinforcing steel. It also includes their relationships and their processes. That system is highly fragmented and sub‐optimized; it needs to be restructured. An industry task force, formed to support the authors' research, characterized the current state of the system in terms of adversarial relations, low pay, and failure to learn from project‐to‐project. No one is making an adequate profit, low fees constrain designers from full exercise of their professional capabilities, and drawing quality and design constructability are declining. The task force also proposed a vision of the future state, identified obstacles to its realization and generated basic strategies for overcoming those obstacles. This paper describes these task force outputs and develops its strategies into a plan for reforming the rebar supply system.

Select this Article		Delivering Sustainability: Lean Principles for Green Projects Anthony Lapinski, Michael Horman, and David Riley ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)6 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Corporate facility owners have developed an increased interest in high performance “sustainable” or “green” facilities. The superior long term performance of these facilities in energy efficiency and indoor environment quality makes them excellent investments for both public and private facility owners. However, project budget increases often result due to complex design processes requiring elevated levels of interaction between design and construction disciplines. Lean production principles are able to reduce waste and streamline processes in highly complex development and production environments. When utilized they can greatly shorten lead times, reduce costs, and show considerable promise for improving the delivery of high performance green facilities. This paper reports a research project between Penn State University and the Toyota Motor Corporation into the successful delivery processes for high performance green facilities. Guided by the principles of the Toyota Production System, the objective of this research is to map in detail the delivery processes for high performance green facilities at Toyota. The outcome of this research has revealed the critical factors that contribute to Toyota's success at high performance green facility delivery, thereby providing corporate facility owners with much needed insight to achieve better delivered high performance green facilities.

Select this Article		Building Performance Engineering during Construction T. Michael Toole and Matthew Hallowell ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)7 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Exploratory research was performed into the hypothesis that a substantial number of building performance engineering tasks on design‐bid‐build projects are typically provided by entities associated with the construction phase, not with the AE of Record. The project specifications, drawings, and submittals were analyzed and employees from key project participants were interviewed for five $5–45M building construction projects. Twenty four building performance engineering tasks were required by the project specifications to be performed by entities associated with the construction of the buildings. Many of these tasks had to be completed by a licensed engineer retained by subcontractors or material suppliers. This large number of delegated design tasks indicates the increasing fragmentation of the design and construction process, which has implications for design‐bid‐build, design‐build and lean construction processes. The shift in engineering from AEs to construction entities is proposed to result from decreased design time and profit margins, attempts to minimize liability, increased specialization and increased prefabrication. The compelling preliminary findings suggest additional research is warranted.

Select this Article		Accident Prevention Strategies: Causation Model and Research Directions Panagiotis Mitropoulos, Gregory A. Howell, and Tariq S. Abdelhamid ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)8 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents an accident causation model that identifies the production system factors affecting the accident process, and proposes accident prevention strategies. The model builds on descriptive rather than prescriptive theories of work behavior and acknowledges the inevitability of exposures and errors. It also focuses on the operation as the level of analysis—that is, it focuses on the factors that influence the number of accidents during a construction operation. The model first identifies the production factors that affect the frequency of hazards during a construction activity, and emphasizes the importance of task unpredictability. Then we examine how the production pressures and the tendency to minimize effort increase the workers' efficient behaviors and their exposure to hazards, while safety efforts try to prevent such exposures. Finally, the model acknowledges that exposure to hazards only leads to accidents, if errors or changes in the situation “release” the hazard. Based on this conceptualization of the accident process, the paper proposes accident prevention strategies that do not focus on compliance with safety rules: (1) reduce task unpredictability to reduce the frequency of hazards; (2) improve the work conditions to enable more productive behaviors without increasing the safety risk, and (3) develop error management strategies to prevent, trap and mitigate the consequences of errors. These strategies provide direction for safety research.

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PROJECT, PRODUCTION, AND CHANGE MANAGEMENT

Select this Article		Dynamic Error and Change Management in Concurrent Design and Construction SangHyun Lee, Feniosky Peña‐Mora, and Moonseo Park ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)9 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Concurrent design and construction has gained considerable popularity in the A/E/C industry mainly due to its potential to reduce project completion time. However, recent studies have shown that it may actually introduce more uncertainty than when a sequential method is used as a delivery system. One of the major driving forces that accounts for this phenomenon is the formation of iterative cycles caused by errors and changes, which ultimately generates detrimental ripple effects on project performance. As an effort to address this issue, this paper introduces the Dynamic Planning and control Methodology (DPM), as a comprehensive framework that helps prepare robust construction plans and provide policy guidelines to handle errors and changes. DPM incorporates a system dynamics model as a core framework and a reliability and stability buffering approach to reduce negative impacts of errors and changes. Lastly, the proposed DPM is applied to a real world infrastructure project in Massachusetts, which provides very encouraging support for protecting schedule performance more efficiently against errors and changes.

Select this Article		Key Constraint Analysis: Achieve Lean Processes with the Application of TOC Li Jun Shen and David K. H. Chua ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)10 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Constraint modeling provides an unambiguous means to identify the causes of uncertainties in the construction workflow and consequently it is possible to improve plan reliability and project performance by tackling these constraints in time following certain methodologies and strategies. Besides precedence and resource allocation constraints, another type of constraints regarding the availabilities of resources and information (RI) prerequisites should be explicitly handled in the work plan. Resolving RI availability constraints is a necessary step in low‐level project planning to reduce uncertainties in the supply chain and information flow, enhance plan reliability, and achieve lean process in terms of fewer delays and less schedule disturbance. Among various RI constraints, some result in more adverse impact to project completion than those of others. According to the theory of constraints (TOC), the overall system performance of a production process may be confined by a few critical constraints which should be eliminated with higher priority. Such constraints are collectively called key constraints, the removal of which would directly improve project performance. This paper provides a methodology to prioritize the RI constraints and identify the key constraints for effectively reducing project delays with minimum impact on schedule changes. The application of key constraint analysis has been implemented with the Integrated Production Scheduler (IPS), a constraint‐based planning and scheduling tool which fulfills the principles of lean project management. An illustrative example is provided to demonstrate the application of key constraint determination and resolution to eliminate project delay through resolving the key constraints step by step.

Select this Article		Automatic Construction Process of Prefabricated Buildings on Geometric Reasoning Wenfa Hu ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)11 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Construction process is very important in construction management, development of AI and IT technology provides feasibility of automatic construction. This paper presents a model of geometric reasoning to automatic construction process planning of prefabricated buildings. Based on the principle of construction by disassembly, a prefabricated building can be decomposed into components. Components are disassembled from the building and the sequence of disassembly of components are derived from the connection graph and disassembling directions of the building. On the reverse of the disassembly process, construction process is gotten in the end.

Select this Article		Model to Facilitate Optimization of the Concrete Supply Process L. Darren Graham and Simon D. Smith ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)12 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract The current method of planning a concreting operation is for a construction practitioner to make an intuitive estimate about the quantity of resources (people and plant) required in a particular situation. This has been found to produce inefficient operational performance, which is unacceptable in the contemporary climate where construction contractors receive in the region of 3% of the total project budget as profit. An alternative method of providing such estimates is presented here, which consists of using a computer model, CBRSim, powered by a combination of artificial intelligence and statistical methods, to determine the likely achievable performance in the ready mixed concrete (RMC) supply process. It was found that CBRSim, can recreate past concreting operations with a high degree of accuracy, and thus the output from the model can be trusted to a certain degree. In this paper, a previously unpublished method to attain an optimum performance in the RMC supply process using CBRSim is presented. This entails: undertaking experiments (using CBRSim) to examine the effect of varying the number of truck mixers on performance; from these experimental results an identification of the optimum performance can be made, and the corresponding details regarding the quantities of resources required for an operation can be relayed to a supplier.

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HOUSING

Select this Article		Technical Preconstruction Service Process Model for the Private Real Estate Development Industry Clark B. Pace and Greg Duggan ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)13 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Real estate development can be described as both complex and diverse; complex due to the large number of private companies and public agencies undertaking development in a variety of organizational forms and legal entities; diverse due to the involvement of a great number of businesses across a wide range of sectors, with each having different objectives and operational structure. Further complicating the study of the development process, each property is unique, and subject to ever changing regulation, and often subject to an approval or permitting process that is public, which allows for citizen involvement. Each of these issues creates an environment that is difficult to model. This paper identifies the common practices used by development managers during the technical services phase of the preconstruction process. Each of the activities involved with this process can be considered technical in nature, due to the structured procedures and need for professional consultants.

Select this Article		A Dynamic Boolean Model of Roll‐Over Financing for Residential Real Estate Development in China Nga‐Na Leung, Kevin Grosskopf, Lezhou Zhan, and Raja R. A. Issa ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)14 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract During the past two decades, China has maintained strong growth in residential real estate development, which has become increasingly attractive to foreign investors. However, the People's Bank of China released new housing loan regulations in June 2004 effectively eliminating development subsidies, raising interest rates and equity requirements for both developers and buyers, making debt and public equity expensive and rarely accessible. As a result, developers with limited private equity increasingly have to rely on internally generated cash flow for roll‐over development. Roll‐over financing means using sale proceeds from buildings completed and sold early in the project life‐cycle to finance later construction phases. The key issue for successful roll‐over is to determine the optimal interval between construction phases. However, quantitative analysis of optimal interval would require tremendous work in the traditional discounted cash flow (DCF) models. As a result, this study proposes a dynamic model with Boolean variable constraints, which defines cash flows as Boolean variables, and enables them to change with construction intervals. The dynamic model not only simplifies quantitative analysis for optimal interval, but also depicts a complete picture for decision making in various scenarios. The model is applied to a hypothetical project consisting of four (4) high‐rise residential condominiums developed in sequence in Shenzhen, China. It easily computes optimal intervals in both cash‐constraint and cash‐sufficient situations.

Select this Article		Residential Construction and the Influence of Inspections on Cycle Time Howard Bashford, Anil Sawhney, Kenneth Walsh, and Jacqueline Thompson ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)15 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract A key component of the homebuilding process is inspection of construction by the building permitting agency within the jurisdiction where the work is performed. Several inspections are made throughout the construction process, but four of the inspections, pre‐slab, framing, drywall, and final, lie on the work schedule critical path. This research focuses upon these particular inspections to determine if the inspection failures influence construction cycle time. Inspections of production homes are examined to determine how often these critical path inspections do not pass the first time, and how many reinspections are required. The number of days utilized to pass those inspections and reinspections is also measured and reported. The research finds that, on average, 12 days are required, to pass these critical path inspections, thus adding 8 days to the construction cycle time. When these inspections do not pass the first time the inspection is made, rework and reinspections must be completed before construction can proceed. The results show that this process may occur within the same day as the original inspection, and the subsequent inspection takes place the next day. More research is necessary to determine precisely why these inspection failures occur, what cost is incurred because of such failures, and in turn, what opportunities are lost.

Select this Article		Production Planning Process in Residential Construction Using Lean Construction and Six Sigma Principles Thanveer M. Beary and Tariq S. Abdelhamid ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)16 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract This research is focused on the prevalent practices for production planning in homebuilding companies. The overall research aim is to develop a production planning model that reduces variations and defects (muda and mura), and creates a reliable production planning system The research is based on Lean Construction production planning concepts and Six Sigma methodology. Interviews with professionals from the homebuilding industry were conducted to study the prevalent practices. Data was collected from a homebuilding site and a set of analysis tools was used to analyze the data and find areas of improvement. A production planning process model was developed using the analysis results and a combination of the DMAIC methodology and the Last Planner System. As part of this research, a metric for production planning process assessment is developed and is used in conjunction with the Last Planner System. This paper will report on the metric development and a case‐study implementation results.

Select this Article		National Housing Research Agenda for Construction Management and Production Makarand Hastak, Michael A. Mullens, and Matt Syal ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)17 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract On February 12, 2004 the National Science Foundation (NSF) sponsored a workshop to define a national housing research agenda. The three‐day workshop was held at the University of Central Florida in Orlando. Workshop participants included 39 faculty members representing 26 universities, a researcher from the National Association of Home Builders (NAHB) Research Center, and a researcher from State Farm Insurance Companies. Representatives from NSF and the U.S. Department of Housing and Urban Development (HUD) also attended. Most faculty participants were invited as representatives of their NSF‐Partnership for Advancing Technology in Housing (PATH) research teams. These participants were supplemented with a limited number of additional faculty/researchers from the universities represented in National Consortium of Housing Research Centers (NCHRC). The workshop was organized into five topical areas: 1) construction management and production, 2) structural design and materials, 3) building enclosures, energy and indoor air quality (IAQ), 4) housing technology, community and the economy, and 5) systems interactions and “whole house” approach. This paper provides a brief overview of the workshop and presents findings in the construction management and production area, summarizes the state of the art in research and recommendations for future research directions. In summary, metrics, methods and tools must be developed to achieve the desired improvements in homebuilding performance. Research is recommended in the following areas: 1) enhancing demand side pressure for quality, 2) developing fundamental construction theory, 3) coordinating the disaggregated supply chain, 4) developing shell and infill processes and technologies, 5) balancing off‐site and on‐site production, and 6) innovation in safety, quality, scheduling and cost management systems.

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SUSTAINABILITY IN CONSTRUCTION OF BUILDINGS AND ROADS

Select this Article		Life Cycle Assessment of Residential Buildings Luis Ochoa, Robert Ries, H. Scott Matthews, and Chris Hendrickson ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)18 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Residential building construction represented about 4.2% of the US Gross Domestic Product in 2000, and residences consumed nearly 20% of total US energy consumption. However, design and construction of residential buildings is often not conducted with an analysis of the life cycle costs and environmental impacts. In this paper, we outline an approach to a life cycle analysis for residences, using the results of a typical construction cost estimate to map into tools for environmental life cycle assessment (using the Carnegie Mellon economic input‐output life cycle assessment model) and for resources required during the use phase of residences (using the DOE Energy Saver model). In essence, material costs are mapped into input‐output sectors and the EIO‐LCA model applied to assess environmental impacts. Similarly, operating inputs such as electricity or natural gas are estimated from the Home Energy Saver model and mapped into EIO‐LCA sectors. The result of using our toolset is a life cycle assessment based upon the construction cost estimate. We are limited in the life cycle assessment to the building costs and the impacts calculated by the Carnegie Mellon economic input‐output life cycle assessment.

Select this Article		Decision Support Tool for Environmental Analysis of Commercial Building Structures Angela Acree Guggemos, A.M.ASCE and Arpad Horvath, A.M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)19 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract The life‐cycle of a commercial building includes: raw materials acquisition and manufacturing, construction, use, maintenance, and end‐of‐life. To date, environmental research has focused on the energy use, environmental emissions, and waste generation associated with creating building materials and operation during the building use phase. Environmental effects of construction, maintenance, and end‐of‐life phases were either ignored or assumed to be insignificant. To truly understand the environmental impact of a commercial building, the environmental effects from all life‐cycle phases should be known. Impacts of concern include energy use, greenhouse gas emissions (CO₂, CH₄, N₂O), related emissions (CO, NO₂, SO₂, VOC, HC), water consumption, waste generation, particulate matter emissions, and heavy metal discharges. To respond to the need for a tool to evaluate the environmental effects of the construction phase of commercial buildings, the Construction Environmental Decision Support Tool (CEDST) was created. CEDST allows designers and contractors to estimate the energy use, environmental emissions, and waste generation associated with the construction of commercial buildings. The categories evaluated include: manufacturing of temporary materials, transportation of equipment and materials, equipment use, and waste generation. To show how contractors can use CEDST to help reduce their energy use and environmental emissions, an analysis is performed to compare the energy use and environmental emissions resulting from the use of alternate construction materials and methods for cast‐in‐place concrete formwork.

Select this Article		Economic and Environmental Implications of Construction Energy Use and Generation under New EPA Emission Standards H. Scott Matthews, Michael Roth, Aurora Sharrard, and Melissa Bilec ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)20 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract The construction industry is responsible for many environmental impacts, primarily air emissions, waste generation, and use of land, water, and energy. Most of the attention has focused on the environmental impacts of material selection and building operation. In this paper, we focus on the energy and environmental implications of construction, specifically on‐site energy consumption including on‐site electricity generation. Existing estimates of energy use and environmental emissions in the construction sector are tied to large construction vehicles, but many other engines and vehicles consume energy. We create a framework for broadly considering the energy use and environmental impacts of construction engines, vehicles, and activities. We estimate the impacts of this energy use and compare it to other known national‐level impacts. Finally, we discuss the possible implications of new EPA regulations on diesel fuels and engines that may lead to a significant reduction in environmental impacts. We propose design changes for large construction equipment that would provide excess power that could be used to replace existing inefficient portable generators. If fully implemented, on‐site electricity generation could be cleaner—i.e., producing fewer emissions, than the electricity grid.

Select this Article		Sustainable Roadway Construction: Energy Consumption and Material Waste Generation of Roadways John A. Gambatese and Sathyanarayanan Rajendran ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)21 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Sustainable roadway construction can be defined as the optimal use of natural and man‐made resources during the roadway lifecycle causing negligible damage to the environment. Two means of improving the sustainability of roadways are to minimize the amount of energy consumed for their construction and to efficiently use roadway materials to reduce waste. This paper describes two separate studies conducted to estimate the amount of energy consumed and the amount of waste generated in continuously reinforced concrete pavement (CRCP) and asphalt pavement (AC) roadways from extraction of raw materials through the end of construction. For CRCP, energy is primarily consumed during the manufacture of cement and reinforcing steel, while for AC the majority of energy is consumed during asphalt mixing, drying of aggregates, and the production of bitumen. With regard to material waste, most of the waste generated from CRCP roadways occurs during extraction and production of cement and aggregates. For AC, the extraction and production of aggregates produce the majority of waste. The results indicate that the amount of waste generated is greater for CRCP than for AC. The results of the two studies highlight where sustainable design efforts to reduce energy consumption and waste generation can best be directed in the initial phases of a pavement's life cycle.

Select this Article		Modified Concrete by Using a Waste Material as a Coarse Aggregate Abdulkerim H. Ghailan ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)22 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Natural aggregate is the main source of aggregate used in concrete work in Iraq. Synthetic aggregate is also used in limited scale around the world. An industrial solid waste is produced from iron and steel industry. It was physically treated and fully inspected and incorporated in concrete as coarse aggregate. The concrete mixes were made with three mix proportions 1:1:2, 1:1.5:3 and 1:2:4. Each mix was made with different water/cement ratio to cover wide range of workability. In the present work some characteristics of the prepared mixes are evaluated and discussed. The characteristics include; static modulus of rigidity, rebound number and chemical resistance towards some acids and salts solutions. For comparison purposes conventional concrete mixes are prepared and tested. The results obtained confirmed that the concrete mixes made with the waste material gave higher modulus of rigidity, higher rebound number and higher chemical resistance towards the expose acids salts solutions compared with the conventional concrete mixes. The results obtained insure that the reuse of the waste material gives an approach to solve the pollution problems that arise from an accumulation of the waste in the site of production, at the same time, modified properties are added to the concrete. Especially previous investigations regarding other characteristics revealed that the concrete mixes made with the waste material possessed superior modified properties.

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SUSTAINABILITY IN LIFE‐CYCLE MANAGEMENT

Select this Article		Lean and Green: The Role of Design‐Build Mechanical Competencies in the Design and Construction of Green Buildings David Riley, Victor Sanvido, Michael Horman, Michael McLaughlin, and Daniel Kerr ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)23 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Building mechanical systems play a major role in both initial cost and life cycle energy use in buildings. This research examines the role of design‐build mechanical contractors in meeting energy efficiency and first cost objectives on high performance “green” building projects. Specifically, synergies between lean principles which eliminate process and materials waste are evaluated for alignment with green goals in resource minimization and energy efficiency. The role of design‐build mechanical contractors in achieving green buildings is explored through engineering, design detailing, fabrication, and construction processes. Three illustrative case studies are summarized to illustrate the unique abilities of design‐build mechanical contractors as valuable contributors on green projects. The results of these case studies and interviews with design‐build mechanical professionals are summarized in descriptive tables in which waste reducing lean principles are applied to achieve green results. Key results include the value of integrated design and detailing of mechanical systems, the ability of design‐build mechanical contractors to take on more risk with innovative design solutions, and the benefits of early involvement of expertise in estimating and constructability of mechanical systems on building projects. Implications for the design process of green buildings and the role of energy and mechanical engineering are discussed.

Select this Article		A Prototype E‐Society Portal: Using a Semantic Model to Represent Sustainability Aspects of Highway Projects to Local Communities Tamer E. El‐Diraby and Bo Wang ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)24 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract More than any other industry, the infrastructure has a direct impact on our communities and quality of life. There is a need to utilize the compendium of information technology research and applications to investigate how to engage local communities in the design and configuration of such projects. Systems are needed to explain to communities the various elements of projects, who is sponsoring them, who has the decision powers to develop and approve such components and, more importantly, the impacts of various design options on sustainability. This paper developed an ontology for sustainability in highway construction. An ontology is a conceptual semantic model that attempts to capture human knowledge (both explicit and tacit) in a consistent manner. Ontologies include three main elements: a taxonomy (common vocabulary presented in concept trees), set of relationships (linking concepts across trees) and axioms (limitation/constraints on the behavior of concepts). The ontology was used to develop a portal for broadcasting highway design features to local communities. By browsing through the portal, a user can learn about project elements, the impacts of each element on sustainability issues, who is sponsoring such element and what efforts have been made to reduce any impacts of such elements on local communities.

Select this Article		The Continuous Value Enhancement Process to Efficiently Achieve Sustainable Project Objectives Michael Pulaski and Michael Horman ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)25 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Sustainable building projects present numerous challenges to project management teams that are not always addressed effectively. Few explicit project management processes are available for managing sustainability goals and requirements on construction projects. Consequently, sustainable objectives are often managed separately from other project objectives and treated as “tack ons” to regular project requirements. This creates inefficiencies in the delivery process leading to additional costs and schedule overruns, as well as missing opportunities to improve sustainable building performance. To minimize missed opportunities and maximize the integration and advancement of sustainability in building projects, the Continuous Value Enhancement Process (CVEP) was developed. This process harnesses the knowledge and competencies of construction professionals to enable project teams to take advantage of inherent synergies between sustainable building and constructability practices. CVEP provides a systematic process to evaluate project decisions and generate potential solutions that improve project performance and sustainable project objectives while and monitoring the process with an in‐process metric. In this paper, four tests are described that show how CVEP collects sustainable building solutions that improve project constructability; provides a systematic evaluation process; consistently generates potential value enhancements from project team members; and produces significant sustainable building solutions that result in actual first cost savings. Initial results of CVEP implementation on the Pentagon renovation project indicate that the process is working as intended resulting in previously untapped sustainability ideas being exposed.

Select this Article		Life‐Cycle Cost Analysis of Bridges and Tunnels Yingchun Zhang, David Novick, Ahmad Hadavi, and Raymond J. Krizek ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)26 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents an analysis of life cycle costs for four bridges and two tunnels constructed and operated by the Port Authority of New York and New Jersey. Cost components include the initial cost, repair and rehabilitation costs, and annual maintenance costs. Results show that the maintenance and rehabilitation costs, as a percentage of the initial cost, are reasonably similar for both bridges and tunnels for perhaps the first 65 years of their service life, after which these costs increase significantly for bridges. However, based on cost per square foot and cost per traffic lane, the opposite is clearly true. Only time and detailed cost records for ensuing years will reveal how the two types of structure compare over their entire service lives.

Select this Article		Evaluating Design‐Build‐Operate‐Maintain Delivery as a Tool for Sustainability Peter Dahl, Michael Horman, Teresa Pohlman, and Michael Pulaski ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)27 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Building and other capital projects usually have a clear distinction between project development phases (i.e. design and construction), and the operations and maintenance phases of a facility. Over the life of the facility, operations and maintenance expenses often far exceed the initial cost of a facility. Importantly, the decisions made early in a project have a strong affect on the life cycle costs of a building. Operation and maintenance knowledge needs to be incorporated early in design to make these critical decisions. High performance green building projects extensively use methods to evaluate the impact of design features over the life of the facility. Techniques such as life cycle cost analysis, energy modeling, and daylight simulation help to evaluate long term impacts of building features. Project delivery methods strongly affect the way project teams are brought together, thus impacting the quality of decisions made in a project. Design‐Build has been shown to introduce often crucial and reliable construction input during design to improve the performance of a project. Likewise, the Design‐Build‐Operate‐Maintain (DBOM) project delivery system brings critical operations and maintenance knowledge into design. With this knowledge, better decisions can be made resulting in a higher performing building. As a result, a more efficient and sustainable facility will be turned over to the owner. A review of literature reveals that DBOM has not yet been widely adopted to achieve sustainable project goals. This paper defines the DBOM delivery system, explores the benefits of DBOM, investigates the ability of DBOM to achieve important sustainable initiatives and concludes that this is a promising development for the advancement of sustainable projects.

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PERFORMANCE CONTROL

Select this Article		An Automated Barcode System for Tracking and Control of Engineering Deliverables T. Shehab, Ph.D and O. Moselhi, Ph.D, P.E., F.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)28 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract The use of barcode technology has proven its effectiveness in a number of industries such as retail and manufacturing. This is due to its ability to assist in organizing, storing, retrieving and making use of huge amount of data in an efficient manner. Although, this technology has been explored by many researchers, it has not been yet fully embraced by the construction industry. This paper highlights the potential use of barcode technology in the construction industry. It focuses mainly on presenting an automated system for tracking and control of engineering deliverables such as drawings, reports and specifications. The system utilizes barcode technology and database management systems (DBMS) for performing its task. The paper briefly describes the various types of barcode labels, scanners and decoders and focuses primarily on presenting a barcode system that is designed to facilitate coding of information pertaining to a wide variety of documents produced in the construction environment. It utilizes 92 alphanumeric characters that is coded in accordance to Code 39 system and stores information related to up to 10,000 documents. The paper also presents a schematic diagram for a database system designed to retrieve a wide variety of information in a multi‐project environment. A plan for validating the developed system is also presented.

Select this Article		Automated Materials Management and Control Model R. Navon, M.ASCE and O. Berkovich ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)29 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Building materials account for a high percentage of a project's total cost and therefore are an important and attractive resource to control. A model based on automated data collection for materials management and control was developed. Based on project plans, the model manages and initiates the ordering of materials automatically, the actual flow of materials and the current stock at the construction site. The model operates in a real‐time mode enabling corrective actions to be taken in time. In this manner costs and unnecessary handling of materials are reduced. In addition, up‐to‐date information regarding materials flow is available and different statistical analyses are enabled. The information generated by the model enables the updating of a historical database, which can be used for planning of future projects.

Select this Article		Data Collection System for Labor‐Intensive Projects José H. Loría‐Arcila and Sergio Álvarez‐Romero ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)30 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract This paper describes a research project sponsored by a construction firm primarily involved in affordable housing. The firm has built 1,200–1,500 dwelling units each year for more than two decades, and it is common for the firm to have up to 800 units simultaneously under construction in a single site. The amount of construction data generated in this type of labor‐intensive projects is large and demands substantial time for its collection and processing. It is common to generate and manage up to 20,000 construction activity‐related data every week. Given the importance of data management upon the control phase in these types of construction projects, a data collection system was developed to assist the firm. The system evolved from a multi‐pages weekly report, requiring slightly over 200 man‐hours to be filled and processed, into a electronic document using current computer technology. This, tested and adopted by the firm, has proven to be very efficient since it only requires 40 man‐hours. Most importantly, accuracy of the information and standardization of the process have been the major contribution of the data collection system.

Select this Article		State‐of‐the‐Art Review of Construction Performance Models and Factors Tanaya Korde, Mingen Li, and Alan D. Russell ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)31 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Measuring and assessing construction project performance on an ongoing basis is an important part of management and control of a project. Described in this paper is the current state‐of‐the‐art of research on prediction and explanation of construction project performance gleaned through an extensive literature search that identified 122 relevant articles published over the last 20 years. This review was carried out in support of an ongoing research program that seeks to embed within a decision support system a transparent reasoning schema that operates on fundamental relationships amongst influencing factors as well as user‐defined, experience‐based hypotheses for explaining project performance. Findings from the review are presented in two tables that identify performance measures treated (productivity, time, cost, scope, quality, safety, project success and others), level of analysis (overall project, work package, individual activity), and factors that affect performance outcomes. The paper concludes with a discussion of the findings in terms of areas of consensus, knowledge gaps, and steps to be pursued to develop a robust and practical schema for interpreting project data in order to explain the basis for performance to date.

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SCHEDULING AND CONTROL

Select this Article		The Need for Prompt Schedule Update by Utilizing Reality Capture Technologies: A Case Study Semiha Kiziltas and Burcu Akinci ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)32 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Updating of construction schedules involves prompt and accurate capture of facts from a construction site for progress assessment and for learning from the assessment of site related facts to improve scheduling of upcoming activities. This paper discusses a case study being conducted on a highway construction project to understand the need for and the current practice of capturing, transferring and storing site related factual data for assessing the status of a project and of how this information is used in scheduling of upcoming activities. It highlights the challenges and opportunities for improvements observed in data collection and situation assessment processes. The case study findings are used as a basis for a discussion on possible ways of improving the current process by utilizing automated data capture technologies.

Select this Article		Realtime 4D CAD + RFID for Project Progress Management Sangyoon Chin, M.ASCE, Suwon Yoon, Yea‐Sang Kim, Jeongwon Ryu, Cheolho Choi, and Chang‐Yon Cho ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)33 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract This research presents the integration of 4D CAD with RFID (Radio Frequency IDentification) technology to improve the progress management process. The objective of this research was to build an effective and efficient project progress management framework by integrating 4D CAD with RFID technology under a collaborative environment throughout the supply chain of a construction project. This research proposes a system, named 4D+RFID, that presents building elements in 3D CAD models according to as‐built progress, where the as‐built information is collected in real‐time by sensing the progress throughout the supply chain using RFID. 4D+RFID developed in this research aims at supporting processes with a focus on structural and curtain wall elements, such as steel columns and beams, concrete slabs, and curtain walls, which are typically on the critical path of project schedules in high‐rise building construction projects. The process is that RFID is applied to sense the progress status of ordering, delivery, receiving, and erection of building elements, and then the as‐built progress information is presented in 3D CAD models. 4D+RFID is under development for use in a high‐rise office building construction project in downtown Seoul, Korea.

Select this Article		Integrated Cost and Schedule Control: Variables for Theory and Implementation Youngsoo Jung ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)34 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract The purpose of this paper is to identify the variables for integrated cost and schedule control in terms of reducing required workload. Potential variables including project delivery system, contract type, level of outsourcing, degree of specialization, progress measurement methods, budget format, management detail, vertical integration, and so on are identified first. The variables are then reviewed in order to detect any interdependences. An evaluation of these variables is performed by estimating the potentiality of reducing workloads. Two real‐world cases are briefly introduced in order to illustrate the practical application of variables identified in this paper. Details and implications of the case studies are outlined as well.

Select this Article		Productivity Evaluation of the Conventional and GPS‐Based Earthmoving Systems Using Construction Simulation Seung‐Woo Han, Sang‐Youb Lee, and Daniel W. Halpin ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)35 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Over the past few decades, the construction industry has pursued productivity and quality improvement, enhanced safety, and reduced operational cost by applying geospatial data collection technologies. One solution, Global Positioning System (GPS) is being currently and applied to earthmoving operations with several benefits over conventional systems in efficiency, performance, and safety. Basically, a GPS‐based system provides a stake‐less operation controlled by the operator who is on the vehicle. The operator is informed of information such as the amount of cut and fill volumes associated with precise elevations and the current location of equipment in real time. With these enhanced functions provided by GPS, the GPS‐based system can achieve productivity improvement by the simplification of surveying tasks and reworks which are not required. However, planners and estimators have been struggling with the lack of data for evaluating GPS‐based systems versus conventional systems prior to commencement of site work. The objective of this study is to present application models for evaluating performance of the conventional and the GPS‐based systems using Web CYCLONE, a simulation methodology.

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ROBOTICS

Select this Article		Instrumenting an Asphalt Vibratory Compactor for Automation of Roadway Compaction R. A. Tarefder ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)36 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract The work presented in this paper is a part of an ongoing research to predict the relative density of an asphalt mat in real‐time during compaction in the field. In this paper, compaction results from a laboratory asphalt vibratory compactor (AVC) are presented. In laboratory test setup, the AVC was instrumented with tri‐axial accelerometers connected to a computer equipped with a data acquisition card. Several asphalt mixes were compacted in the AVC and the vibration responses were recorded. The relationships between the vibratory response and the various process parameters such as: sample thickness, mix types, temperature vibration frequency, compaction pressure, etc. are examined. For selected mixes, the vibration properties (i.e. frequency) are evaluated using spectrogram method. The results show that the spectrogram of vibration response can represent the degree of compaction. The study results demonstrate that the similar (spectrogram) approach can be used to monitor the compaction process of asphalt pavements in real time by instrumenting the filed vibratory roller.

Select this Article		Fully Autonomous Robot for Paving Operations L. Sebastian Bryson, Christopher Maynard, Daniel Castro‐Lacouture, and Robert L. Williams, II ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)37 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Efficiency is low in conventional concrete construction. This fact, combined with high accident rates at construction sites, low product quality, and insufficient controls of the project schedules have led researchers to develop autonomous robots to perform specific tasks. Such robots are highly advantageous for a multi‐task operation such as concrete paving. Concrete pavement construction is ideally suited for robotics in that the complete construction process is made up of many single‐tasks that can be automated and integrated into a single machine. Although the state‐of‐the‐art paving process includes a high level of automation, the process is still labor intensive and the final quality of the pavement section is a function of the skill of the paving crew. Introducing autonomous robotics into paving operations provides a means to consistently produce high‐quality products, faster and safer than conventional concrete paving techniques. Ohio University is developing a 1:20 scale prototype of a fully autonomous robot for concrete paving called RoboPaver. The purpose of the prototype is to serve as a proof‐of‐concept concrete pavement construction robot. The full‐scale version of the RoboPaver will occupy about the same volume as a typical commercially‐available slipform paver, but will combine all the operations of a conventional paving system into one robot. The RoboPaver prototype will also implement an intelligent concrete construction system that will allow real‐time remote monitoring and control of the paving operations, based on sensors and other machine performance data. The tangible benefits of using RoboPaver for pavement construction will include lower labor costs, lower equipment maintenance costs, less construction downtime, and lower demobilization and cleanup costs. Other potential RoboPaver benefits include increased construction site safety and higher quality of the finished pavement section, both of which can be directly related to a reduction of overall project costs.

Select this Article		Climbing Robots with Adaptive Grippers for Construction M. Rachkov, V. Gradetsky, and M. Knyazkov ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)38 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Climbing robots are intended to move over vertical and slope surfaces to fulfill different technological operation by means on‐board equipment. Vertical surfaces of buildings can be porous and rough so the robot should perform adaptation to such kinds of surfaces. The paper presents a new climbing robot for construction tasks that has adaptive possibility to move over various surfaces by means of a vacuum adaptive gripper system. It includes pressure, flow and force sensors, sealing gripper design and feedback control system of pedipulators. The control system ensures a sealing mode of adaptive pedipulator motion. The robot has two platforms and a light skeleton structure with nine degrees of freedom including two flexible technological manipulators. The climbing robot design allows adaptation to vertical surfaces of different quality. The design of the robot, its technical characteristics and experimental results are discussed.

Select this Article		Current Research and Development and Approach to Future Automated Construction in Japan Junichiro Maeda ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)39 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Automated construction technologies have been developed and introduced in the Japanese construction industries since the 1980s. However, the construction industry remains a craft‐oriented and labor‐intensive industry with minimal automation of tasks. Automation of construction processes has potential significant effects on construction of buildings. This paper describes the history of research and development of automation technology in Japan and the advantages to using construction robots and automated building construction system at the field level, and examines possible application and requirements in future construction operations. In addition, current research and development of robotics technology is introduced with concrete examples.

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EDUCATING TOMORROW'S CONSTRUCTION LEADERS

Select this Article		The Integrator Model for the Construction Professional of 2020 Paul S. Chinowsky and Anthony D. Songer ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)40 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract The construction industry is changing based on external forces and changes in the workforce. Responding to these changes requires a professional with a new set of skills and knowledge. In an effort to identify these skills and knowledge, the National Science Foundation sponsored a workshop where industry and academic professionals gathered to define the Construction Engineering Professional of 2020 (CEP 2020) and call for organized action toward investigating education and research issues within the CEP 2020 domain. This paper details the results of that meeting and the introduction of the Integrator model as the foundation for the CEP 2020 professional. Barriers and opportunities for this model are introduced together with its potential impact on the education and research communities.

Select this Article		What Is the Background of Future Construction Leaders in Mexico? José H. Loría‐Arcila and Jorge A. Vanegas ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)41 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract This paper reviews the background of the newcomers that we are “formally” educating in construction related programs in Mexico. Most of them come from either Civil Engineering or Architecture, and only a few from Construction Engineering or Building Construction programs. Curriculums at these programs in the past have been too rigid, namely a fixed set of courses for all students without or with just few electives. The most recent trend is to educate generalists, who may specialize later in a particular field of their choice, construction for instance. There is evidence that students enrolled in those programs, on the average, take only a few construction related courses, and only a couple of management related courses, after four or five years of college education. However, many of them will incorporate into the construction industry. This raises the question: Is this the proper approach? It appears that today's programs are failing to provide proper education to the future construction actors, at least at the undergraduate level. Moreover, they are not being prepared to carry out properly their roles as construction leaders, particularly in the management arena. What is the solution then? How to combine the needs for educating generalists and at the same time prepare them as future (management) leaders for the construction industry? The authors propose in this paper a perspective that may allow a gradual learning process, both theoretical and practical, for those interested in pursuing a career in construction.

Select this Article		Leadership and Goal‐Setting in Construction Education William W. Badger, Kenneth Walsh, and Richard Mayo ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)42 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract An evaluation of the processes by which students develop their leadership and management skills and the paradigms that they hold was completed at the Del E. Webb School of Construction at Arizona State University. Student papers on the subject of leadership and management were analyzed to identify leadership traits most important to construction students. The most common traits that the students identified as needed by good leaders are communication skills, the ability to empower and delegate, trust and respect, ethics and morality, and people skills, in that order. A “living lab” was developed to determine when and how students develop their understanding of leadership traits. It was concluded that more than approximately 70% of the influences that define a student's understanding of good leadership skills occur prior to college attendance. This paper presents the processes used for the evaluation and some observations based on student responses. The job of the faculty, therefore, is build upon that understanding, building confidence and opening new avenues, expanding areas of interest, and raising student expectations.

Select this Article		Aspects of Learning and Knowledge in Construction Projects Patrick S. W. Fong ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)43 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract The construction industry is viewed globally as a project‐based industry, as project personnel move from project to project upon completion. Society is also becoming knowledge‐based, so that knowledge can provide firms with competitive advantage in this age of dwindling resources. As a result, two important issues arise that require our careful attention, i.e. the knowledge and learning aspects in construction projects. These issues influence the working of companies' employees as well as the quality of service provided to clients. CEOs from 200 top international design firms and 225 top international contractors were selected for this study in June 2004 with a 15.5% response rate. The study emphasizes that project‐based organizations face many difficulties in ensuring adequate learning and knowledge sharing within and across projects, as projects themselves do not share experiences with other projects routinely and naturally. Both personalization and codification knowledge‐sharing mechanisms should be properly deployed to projects in order to prevent employees from reinventing the wheel and leveraging on companies' knowledge stocks.

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INNOVATIVE CONSTRUCTION EDUCATION

Select this Article		Interprofessional Issues in Construction Education Tony Selman and Tony Westcott ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)44 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract One of the distinctive features of construction education at the University of the West of England Bristol is that it takes place in a Faculty of the Built Environment in which interprofessionalism is a key educational principle. Interprofessional Issues, or Interdisciplinary Issues as it has been renamed this last year, is the final year module in a series of modules designed to develop the interprofessional theme in the Faculty's undergraduate programme of studies. The paper explains how the module philosophy has developed since its inception in 1992, together with an analysis of the pedagogic issues faced and addressed by the module team.

Select this Article		Lessons Learned from a Design Course Utilizing Object‐Based Learning Method Joo Hyoung Lee and Bob G. McCullouch, P.E., M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)45 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract This paper describes the lessons learned from using a digital object‐based learning method in a paperless course, CE 526 Design of Temporary Structures at Purdue University. The primary purposes of the evaluation are to assess the impact of Object‐Based Learning Model (OBLM), refine the learning method, and improve the delivery system in accordance with students' needs and feedback. For this reason, students participated in three online surveys, Initial, Intermediate, and Post Surveys, throughout the course, and then the survey results are statistically evaluated and reviewed. The evaluation has several steps: setting up evaluation method, data collection, and a statistical analysis. The evaluation is focused on substantiating the effectiveness of the OBLM in engineering education by examining students' opinions. The evaluation results are statistically and verbally discussed and concluded with lessons learned from the course.

Select this Article		Understanding Cognitive and Metacognitive Processes in Construction Management: The System Dynamics Perspective Amlan Mukherjee, Eddy M. Rojas, and William D. Winn ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)46 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract The fragmented and de‐contextualized nature of the construction management (CM) curriculum does not adequately prepare students for the industry. In order to create a more appropriate CM curriculum, we feel it is imperative to examine the nature of learning in the CM domain. How do novice construction managers learn? How do they build expertise through experience? Most importantly, what tools do we have that will allow us to educate novice construction managers and provide instructors with guidance in answering these questions? We have argued that the CM domain can be modeled using system dynamics. Based on our observation of the students interacting with the Virtual Coach, a situational simulation environment, we have concluded that students in CM learn by developing a better understanding of the inter‐relationships of the sub‐components of the CM system (cost, schedule, and resource availability) and its evolution over time. We also contend that tools like the Virtual Coach can be very useful in helping us better educate construction managers.

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MANAGING CONSTRUCTION PROFESSIONALS

Select this Article		Attitudes in Construction Safety Brenda McCabe, Dimitrios Karahalios, and Catherine Loughlin ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)47 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract After years of decreasing injuries in the construction industry, a reduced improvement trends and occasional spikes in injury and fatality rates have been observed. We know that there exist sufficient rules, regulations, and requirements; so what is the cause? A group of researchers, including two engineers, an economist, and a psychologist, are investigating attitudes toward safety in the construction industry. A survey was developed to collect demographic, attitudinal, and incident data. To date, several hundred workers and supervisors have participated in the survey. Interim results are being generated to understand trends in the data. This paper reviews these interim results, and looks to provide insight and suggestions on how contractors might improve their safety programs.

Select this Article		Exploring Mental Models of Construction Managers Amlan Mukherjee, Eddy M. Rojas, and William D. Winn ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)48 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Experience is a critical component of expertise for construction managers. Time allows them to inductively construct and organize knowledge about the construction management domain that often cannot be easily formalized. The goal of this study was to investigate the nature of expertise in construction managers. Both experts and novices represent and organize experientially gained knowledge as abstractions that we refer to as “mental models”. We investigated expertise by exploring mental models of construction managers. In this study we explored experimentally the existence of a difference in the mental models among construction managers. A group of construction managers with varying levels of experience were asked to respond to a construction management crisis scenario. Using the ConProFac software to calculate an index i indicative of the structuredness of the responses we found a significant correlation between i and the number of years of experience of the respondent. A better understanding of the mental models of experienced construction managers will help in developing a better theoretical understanding of the CM domain, while also enriching the construction management educational experience.

Select this Article		Cross‐Cultural Virtual Design Teams: Cultural Influences on Team Performance in Global Projects Tamaki Horii, Raymond E. Levitt, and Yan Jin ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)49 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Globalization of the construction industry has brought unique challenges such as coordination among project participants from different countries. This research attempts to understand cultural differences in international joint‐venture (IJV) teams composed of Japanese and American participants, and to develop a prototype computational model—“Cross‐Cultural”‐Virtual Design Team (CC‐VDT)—to seek better organization designs for cross‐cultural engineering teams. Based on our case studies, we characterize cultural differences along the dimension of cultural values and cultural practices. Cultural values refer to an individual's preferences in decision making and communication. Cultural practices include the cultural norms for adopting specific coordination mechanisms to control organizations and tasks. CC‐VDT incorporates value‐practice dimensions based on our observations and a literature survey. The simulated results of the effects of cultural impacts are qualitatively consistent with cultural contingency theory and our observations, validating the reasoning of CC‐VDT. These results extend the possibility of using simulation modeling to capture distinguishing cross‐cultural phenomena that emerge in global construction projects.

Select this Article		Understanding and Mitigating Challenges on Global Projects: The Role of the Freelance Expatriate Ashwin Mahalingam and Raymond E. Levitt ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)50 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Global construction projects that involve collaboration between participants from multiple countries result in unique challenges that are not faced on intra‐national projects. In order to further investigate this phenomenon, we conducted detailed case studies on four, matched international construction projects—two in Taiwan and two in India. Through our study we found four key differences in institutionalized work practices that led to large challenges on projects. How were these institutional challenges mitigated? We found that a group of freelance professionals, hailing mainly from the UK but also from other parts of the British Commonwealth, acted as the mediators or catalysts in resolving these differences. In this paper we describe the types of problems that arose on the project and the nature of the expatriate freelance community. We also analyze some of the strategies adopted by its members, and the ways in which conflicts were solved.

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SUPPLY CHAIN MANAGEMENT

Select this Article		MANS3C: An Agent‐Based Multi‐Attribute Negotiation Framework for Construction Supply Chain Coordination Yaowu Wang, Xiaolong Xue, and Qiping Shen ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)51 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract There are many problems in construction process, such as fragmentation, budget overrun, time overrun and high waste, most of which are supply chain problems and often caused by the lack of coordination and information sharing across organizations in the supply chains. Supply chain coordination (SCC) is a critical success factor for the application of supply chain management to effectively improve construction performance. An agent‐based multi‐attribute negotiation framework for construction SCC (MANS3C) is designed, which adopts the agent technology and regards construction supply chain as a typical multi‐agent system. This framework integrates the specialty agents (contractor agent, designer agent, supplier agent, owner agent, etc.) and service agents (coordinator agent, monitor agent, name server agent) into a multi‐agent system on the Internet to improve decision‐making efficiency and information sharing. Since different participants in the supply chain have different preferences on decision‐making attributes, such as cost, time, quality, safety and environment, a multi‐attribute negotiation mechanism is established by constructing a multi‐attribute negotiation model, describing the multi‐attribute negotiation process, and designing the multi‐attribute negotiation protocol. The establishment of this mechanism is based on the negotiation theory and utility theory, and aimed at promoting the coordination between specialty agents. A prototype system is developed and tested on a hypothetical construction project. The test indicates that MANS3C can solve problems in construction supply chain and provides a solution to construction SCC.

Select this Article		Legal Risk Analysis, Modeling and Programming for E‐Commerce in Construction Ihab A. Ismail, S.M.ASCE and Vineet R. Kamat, M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)52 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents an aspect of the ongoing research at the University of Michigan aiming to analyze the status of e‐commerce in the construction industry. It identifies impediments and challenges, and research solutions for the identified challenges. The focus is on risk management and legal challenges for e‐commerce in construction. Very little, if any, research exists on this area in construction literature. The premise of the argument is that studying the legal aspects and challenges for e‐commerce in construction are an essential element to having a strong e‐commerce infrastructure. This paper introduces the concept of legal modeling and programming for e‐commerce in the construction industry. To present the argument for legal programming, the paper starts by outlining the taxonomy of construction e‐commerce risks and introducing the legal risks of doing business through e‐commerce in construction. It then looks to the future and considers how to incorporate legal criteria in e‐construction applications, design and programming.

Select this Article		Taxonomy for International Construction Market Entry Mode Selection Chuan Chen and John I. Messner ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)53 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract To achieve sustainable business growth in the competitive international construction market, contractors must carefully and intelligently design or review their geographic market entry strategies. With rapid changes in the international construction arena, there is an increasingly wide range of optional entry modes that international contractors can use to meet specific conditions in accessing target attractive markets. A taxonomy of these entry modes can provide a comprehensive and systematic basis for international construction firms to conceptualize their entry activities and identify alternative or complementary entry modes or combination of entry modes. This research investigated ninety four entry cases of leading international construction companies from around the world, characterized different entry modes with study of these cases, and identified their interrelationships in terms of flexibility and compatibility. Based on this analysis, a taxonomy of nineteen entry modes for international construction markets is proposed. This taxonomy was validated through a questionnaire survey of seasoned industry practitioners.

Select this Article		Planning to Get Work: An Evaluation of Market Forecasting Techniques for Use by Large Designed Construction Firms Otto Fetterhoff and William J. O'Brien ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)54 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract This research examines market forecasting techniques for use by large design and construction firms working in the nonresidential construction‐market. The intent is to help large firms focus their resources on the markets with the most opportunity several years in advance. Specifically, the research applied five existing and one new forecasting methodology to the task of analyzing and prioritizing multiple construction‐markets. The six forecasting methodologies were used to estimate nonresidential construction activity in all 67 counties of the State of Florida. A 13‐year time period was used (1990–2002) and over fourteen thousand data points were collected for 17 variables in each county in each year. This data set provided a basis for comparative validation of the forecasting techniques. The variable total tax revenue was found to be the best indicator of future non‐residential permit activities. Somewhat surprisingly, there was a low correlation between residential and non‐residential permit activities. Overall, the research findings demonstrate that forecasting methods are useful tools to help design and construction firms identify and prioritize new markets for future growth.

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PRODUCTIVITY AND METHODS I

Select this Article		Prediction of Productivity for Microtunneling Projects in Bidding Phase Mohamed Y. Hegab, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)55 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract The need for utility service line replacement or repairs with minimum disruption to the surface has increased the demand for trenchless excavation methods like microtunneling. Microtunneling is a trenchless technique that is used in installation of new pipelines. Microtunneling can be applied in gravity and pressure lines, permanent ducts for cables, and crossings under rails or roads. When bidding a microtunneling project, the main concern of microtunneling contractors is predicting the underground behavior of the machine. In other words, the microtunneling productivity is the key for profit in microtunneling projects. Contractors use their own experience in predicting approximate productivity, which risks cost estimation accuracy for microtunneling projects. Contractors lack productivity models that help them in predicting overall project time. Predicting the overall time for microtunneling projects in different soil types using probabilistic analysis methods is the purpose of this paper. Low, medium, and high performance operation is considered in the models. Contractors can use the models in predicting the overall project time through different soil types in bidding phase. Contractors can use it as well to evaluate the performance of project team. Researcher can use these models to start a more detailed analysis of the bidding process of microtunneling projects.

Select this Article		Predicting the Production Rates of Foundation Construction Using Factor and Regression Analysis Wai Kiong Chong, James T. O'Connor, Jui‐Sheng Chou, and Sang‐Hoon Lee ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)56 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Foundations are often part of the critical path for bridge construction. However, foundation constructions are highly variable due to the fact that construction process faces difficult problems like poor soil conditions, congested traffic and unpredictable weather. Designers are often unable to obtain reliable production rates in order to improve the accuracy of project time estimation that often leads to more delays and disputes. Field construction data related to this research were collected from twenty‐five Texas highway projects within a two‐year period to develop three models that could predict production rates of drilled shafts and prestressed concrete piles more accurately. Analyses showed that these models are estimate production rates accurately and relatively simple to apply and develop.

Select this Article		Economic Assessment of Site Exploration Programs Using Stochastic Dynamic Programming Veerasak Likhitruangsilp and Photios G. Ioannou ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)57 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Site exploration programs are generally used to mitigate geologic uncertainty associated with underground projects. Developing the optimal exploration program for a subsurface project is an extremely challenging task due to the difficulty to assess its economic value in advance and in a quantitative and systematic manner. This paper presents a methodology to evaluate the economic value of sequential subsurface exploration programs by using stochastic dynamic programming. The paper illustrates the application of site exploration programs as a risk reduction strategy for underground projects. A sequential site exploration program is structured as a stochastic dynamic programming model. Effects of test results on geologic prediction are analyzed using Bayes' theorem. Preposterior analysis is performed to evaluate the economic value of the program based on the concept of value of information. A sequential site exploration program is used to illustrate the application of the proposed methodology.

Select this Article		Quantifying the Impact of Schedule Compression on Construction Labor Productivity Chul‐Ki Chang, Awad S. Hanna, Jeffery A. Lackney, and Kenneth T. Sullivan ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)58 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract In a typical construction project, a contractor may often find that the time normally expected to perform the work has been severely reduced. The reduction of time available to complete a project is commonly known throughout the construction industry as schedule compression. Schedule compression is a problem because it negatively impacts labor productivity in various ways, and it becomes a source of dispute between the owners and contractors. This paper investigates how schedule compression affects construction labor productivity and provides a model that quantifies the impact of schedule compression on labor productivity by analyzing 66 mechanical projects and 37 sheet metal projects collected from across the United States. The model can be used in a pro‐active manner to reduce productivity losses by managing the factors affecting productivity under the situation of schedule compression. Another useful application of the model is its use as a litigation avoidance tool after the completion of a project.

Select this Article		Shift Work Impact on Construction Labor Productivity Awad S. Hanna, Chul‐Ki Chang, Kenneth T. Sullivan, and Jeffery A. Lackney ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)59 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Schedule compression or acceleration is a common problem for specialty contractors. Schedule acceleration is often the result of late start, delays and/or added work. Generally, a contractor has three options in accelerating a construction schedule; scheduled overtime, increasing the number of workers, or creating an additional shift of workers. There has been a significant amount of research conducted on scheduled overtime on construction labor productivity. However, little information has been found in the literature addressing the cost implications or labor inefficiency associated with working a second shift. This paper quantifies the relationship between the length of shift work and labor efficiency. The results of the research show that shift work has the potential to be both beneficial and detrimental to the productivity of construction labor. The productivity loss obtained from the quantification model developed through this study range from −11% to 17% depending on the length of shift work used.

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PRODUCTIVITY AND METHODS II

Select this Article		Analysis of Focus Group Data regarding Construction Craft Workers' Perspective of the Factors Affecting Their Productivity Jiukun Dai, Paul M. Goodrum, William F. Maloney, and Colwyn Sayers ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)60 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract This paper examines the preliminary findings of an ongoing research project to identify the factors that influence construction productivity from the perspective of construction craft workers and their immediate supervisors. Eighteen focus group sessions with craft workers and their immediate supervisors from nine construction project sites were conducted to discuss the factors which reduce their productivity. Eighty‐nine issues affecting construction productivity emerged from the group discussions. The major factors are recognized through Pareto analysis. Based on these preliminary data, differences in group responses are analyzed with respect to different criteria including project size, union status, level of project completion, and craftsman/non‐craftsman status.

Select this Article		Application of DEA‐Based Malmquist Productivity Index Measure to the Construction Industry in China Xiaodong Li, Qiping Shen, and Xiaolong Xue ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)61 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Although productivity is not the only determinant of economic growth, it is a measure of the economic prosperity and degree of competitiveness of an industry. Productivity analysis can provide valuable information about the effectiveness of economic policies. It is also a useful tool for policy makers to improve decisions on economic development and industry performance. Data envelopment analysis (DEA) measures the relative efficiency of decision‐making units, which avoids functional specification to express production relationship between inputs and outputs. DEA‐based Malmquist productivity index (MPI) approach has been applied to express the productivity change over time. This paper presents the method for calculating input‐oriented DEA‐based MPI. The MPI, which comprises technical efficiency change and empirical production frontier shift, is used to measure the productivity changes of the construction industry of China's different regions over the period of 1997 to 2002. The calculated results indicate that productivity of the construction industry in China experiences a continuous improvement from 1997 to 2001 and starts a slight decline in the time period of 2001 to 2002. However, there still are different gaps of productivity development level of the construction industry between western, midland, eastern and northeastern regions. It is necessary to adopt effective policies and measures to improve the performance of productivity and competitiveness of the construction industry, and to promote the sustainable development of the construction industry in different regions. The DEA‐based MPI approach provides a practical tool to assist policies design and make strategic decisions for improving the total performance of the construction industry in China.

Select this Article		Effect of Spatial Variables on Bricklaying Productivity Rasha M. Stino, John G. Everett, F.ASCE, and Robert I. Carr, F.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)62 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract This paper demonstrates that spatial variables in the bricklaying environment can have significant impact on masons' productivity. Spatial variables considered were distance above the work surface on which the mason stands and distance to either side of the brick and mortar supply. Ten bricklayers constructed ten brick veneers, each 4.2 m (13ft–8 in.) wide and as high as they could physically reach, which varied from 1.7 to 2.0 m (5ft‐7in. to 6ft‐8in.). The time spent to install each brick was recorded and quality of completed veneers was measured at different vertical and horizontal locations in the brick veneer. Analysis of vertical distance showed that masons had the highest productivity about 0.4 to 1.2 m (1ft‐4in. to 4ft‐0in.) above the working surface. Productivity decreased significantly above and below this range. In comparing the upper and lower extremes, masons were more productive working down low than working up high. Analysis showed masons' productivity was not as sensitive to horizontal distance as vertical distance. Results showed that the central section of the veneers, near the material supply, had the highest productivity. Productivity was lower in the left and right sections of the veneers, which ranged from 1.1 to 1.9 m (3ft‐8in. to 6ft‐4in.) from the center of the material supply. Inspection of quality of constructed walls showed that deviations in head joint and bed joint thickness, horizontal and vertical levelness and alignment of bricks, and rotation of bricks were greatest in the upper‐most and lower‐most courses in the veneers. Overall results showed that avoiding or minimizing bricklaying in the upper and lower extremes of walls increases masons' productivity, and increases quality of work.

Select this Article		Fast and Easy Concrete Construction Using Innovative Steel Reinforcement Mohammad Shamsai and Halil Sezen ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)63 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract A new reinforcement system, Prefabricated Cage System (PCS), is proposed to perform the function of longitudinal and transverse steel in reinforced concrete members. PCS is made from a solid steel tube or plate acting as transverse and longitudinal steel connected monolithically. PCS reinforcement eliminates some of the weaknesses and detailing problems inherent in traditional rebar reinforced concrete construction resulting in easier, more reliable, and faster construction. The confinement provided by PCS is investigated by comparing the results from 6 small‐scale column tests. The specimens were tested by axially loading the concrete core. The effects of PCS tube thickness, and the width and height of transverse and longitudinal steel on the provided confinement and displacement capacity are investigated. Test results show that PCS provides higher confinement capacity than similar rebar reinforcement.

Select this Article		Building the Great Pyramid in about 385 Days: A Case Study in Energy Management Gerard C. A. Fonte ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)64 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract The mystery of building the pyramids can be addressed by examining the individual problems from an energy management approach. A typical estimate for building the great pyramid is 20 years with 25,000 men. The energy management approach indicates that 10,000 workers could, in theory, have completed the great pyramid in about 385 days. However, more reasonable evidence suggests that there were about 4,000 workers who took about four to six calendar years to build the great pyramid.

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PROJECT RISK QUANTIFICATION AND ANALYSIS

Select this Article		A Risk Threshold Calculation Methodology for the Construction Projects Applying Value at Risk Seon‐Gyoo Kim, Jae‐Jun Kim, and Kyung‐Rai Kim ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)65 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract A risk management technique rapidly becomes one of the critical project management methodologies to achieve project objectives and improve its performance in gradually increasing uncertainties surrounding the construction environment. However, as most risk management techniques applied to the construction process have been not only focused on a conceptual and planning phase for project life cycle but also performed a risk analysis only, they are not regarded as a general project management tool such as time, cost and quality management that are usually conducted during a whole construction process. Therefore, this paper proposes an unique and creative construction risk response process based on the risk threshold and its calculation methodology applying a concept of VaR (Value at Risk) in order for a construction risk management to be functioned as one of the general project management tools in the construction process.

Select this Article		Modeling Cost Escalation as a Risk Factor in Construction Projects Ali Touran and Ramon Lopez ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)66 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract This paper describes a computer model designed to incorporate the effect of cost escalation on large construction projects. The computer model is especially designed to work with large construction programs consisting of several projects spanning over a period of several years. By knowing the precedence relationships between projects and modeling the effect of escalation probabilistically, a distribution is calculated for the total program cost. There are two main contributors to cost variation in such projects: (1) delays for each individual project that may have an impact on total program finish time, and (2) the uncertainty in the value of escalation factor, especially in multi‐year projects. The computer model developed as part of this research is capable of modeling the escalation rates as a random variable from a normal distribution assuming escalation rates to be correlated in subsequent periods. Further, it can model each project duration as a random variable. By simulating the model, the user can obtain distributions for total construction program duration and cost. Using these distributions, the management will be able to assess the extent of possible cost overruns due to cost escalation or the adequacy of the proposed budget. A few approaches consider the effect of the delay on cost but even when they perform integrated cost and schedule uncertainty analysis (Monte Carlo), they utilize a deterministic rate to consider the effect of cost escalation. This computer model will take into consideration the uncertainty and variability of both schedule and escalation factor in a more integrated probabilistic approach. The application of the computer model is demonstrated through a realistic example and the results are discussed.

Select this Article		Assessment of a Four Moments and Pearson Distribution Approach for Risk Analysis in Construction Estimates and Economics Ahmed M. Abdel Aziz and Alan D. Russell ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)67 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract The use of a standard four moments approach has been advocated in the past for risk analysis of construction project estimates and economic measures. The approach calls for the computation of the four central moments of the performance function using an approximated Taylor series expansion. The four moments are then fitted to a distribution from the Pearson distribution family. In instances where this approach yields accurate results, it can offer a significant alternative to simulation. However, in instances of high non‐linearity of the performance measures, results from such an approach do not match well with those from Monte‐Carlo simulation. This paper investigates this issue and introduces an expanded four moment formulation that provides a more accurate estimate of the moments than that offered by the standard moment approach. A number of examples using summation, multiplication, division, and exponentiation were used to investigate and compare the three approaches, with attention being limited to independent variables (i.e. no correlation). The results of the analysis demonstrate that the expanded four moments give better estimates than the standard moment approach. However, it is shown that when performance measures involve variables of higher exponent/power, both approaches produce results significantly different from those obtained by simulation.

Select this Article		Attitudes of Contractors and Employers Towards Transfer of a Time‐Related Risk in Construction Contracts Maria C. Y. Au and Edwin H. W. Chan ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)68 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Risk allocation through contractual provisions involves financial considerations. To enhance the cost effectiveness of risk adjustment exercise, we have to assess the risk behaviors of both contract parties, which are termed as “contractors' request to pay” and “employers' willingness to pay” in this paper. Owing to the significant impact that inclement weather imposes on project delays, the paper focuses on the risk shift of deleting Extension of Time provision due to inclement weather. Within the expected utility approach for studying one's risk behavior, we should adjust for risk perception and risk attitude to obtain one's subjective values. This is supported by empirical studies showing significant differences between expected utility and subjective values. Some researchers have reported high correlation between attitude and behavior, but others have found only insignificant relationship. Therefore, in this study, the term “situational variables” is introduced to fill in the possible gaps between risk attitude and behavior, on the ground that such variables may not have any significant correlations with one's risk perception or attitude, but may relate to some other commercial decisions instead. This paper aims to examine the relationships among one's risk behavior and its major constituents — expected utility, risk perception, risk attitude and other “situational variables”, together with the proposed methods in calculating the “request to pay” and “willingness to pay”.

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PROJECT MANAGEMENT DECISIONS AND METHODS

Select this Article		Is a Small Project Really Different? Lilin Liang, Stephen R. Thomas, M.ASCE, and G. Edward Gibson, Jr., M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)69 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract The trend towards smaller capital projects within the engineering and construction industry has many implications for project management. Organizations executing predominately small projects typically handle more estimates, procurements, and subcontracts. Practices for managing large projects often are less effective for managing small projects. Research indicates that different approaches are warranted for the management of these projects. This paper, based on research conducted at the Construction Industry Institute (CII), outlines differences in managing small projects. It also presents the development of a survey questionnaire designed to evaluate small project performance and the implementation of project management practices developed for these projects. Data from 356 small projects have been collected through the CII Benchmarking & Metrics Program to produce performance indicators such as cost and schedule growth, change orders factors, and safety metrics. These are compared with metrics from 521 large capital projects, also from the CII database. Differences in project performances identified in early analyses will suggest that project owners are exposed to higher risks when managing smaller projects. This paper will summarize key finding of this research and provide guidance to practitioners in how to manage small projects.

Select this Article		Defining Megaprojects: Learning from Construction at the Edge of Experience Christine Fiori and Molly Kovaka ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)70 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Construction megaprojects have been undertaken with increasing frequency in the past century. Many of these projects have experienced high cost overruns, extensive delays, and heated conflicts. To this point, numerical thresholds around $1 billion have been used to define megaprojects, however, the characteristics that elevate a project to mega‐status are much more complex than simply project cost. Formulation of a transparent, relevant, and useful definition of “construction megaproject” is the primary subject of this paper. A project metric is developed as a basis for comparative studies, using five common megaproject characteristics. In addition, the framework for a descriptive and comparative megaproject tool is developed. Six megaproject case studies are evaluated using the proposed definition and megaproject tool as a methodological framework. Conclusions about the critical importance of two characteristics, risk and ideals, were drawn from the case studies.

Select this Article		Evaluating the Consequences of Overlapping Dependent Activities Susan M. Bogus, James E. Diekmann, and Keith R. Molenaar ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)71 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract There are many benefits to reducing project delivery time by overlapping dependent activities. When considering the overlap of dependent design activities, one must also consider the consequences that may result from overlapping. Speeding up the design delivery process is not without risks or costs. Limiting the adverse consequences of overlapping requires a planning framework that appropriately evaluates overlapping strategies and the desired degree of overlap. The planning framework must also evaluate the consequences of overlapping dependent activities in terms of additional design and construction costs as well as the potential for rework. The large number of variables in the overlapping decision makes an analytical solution complex. After a review of analytical solutions to the overlapping problem, such as simulation and optimization, a basic decision algorithm is presented as an initial solution to this complex decision problem.

Select this Article		Emerging Methods for Defining and Managing Dynamic Project Requirements Karen Lee Hansen and Jorge A. Vanegas ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)72 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Construction projects involve the integration of many technical sub‐systems and components in a context that often involves complex and sensitive economic, social, political, and environmental decisions. This form of organization is typified by a management and decision‐making climate in which problems are highly interdependent while the people, methods and organizations involved are extraordinarily independent. Currently, the flow of information from early debates and strategic project definition through design, engineering, procurement, construction, operation and decommissioning is piecemeal. Design programming and the strategic support of decision making through the life of a building project is an important factor for successful project outcomes. The automation of design programs can allow enhanced linking of client/user requirements to design, construction, operation and post‐occupancy review. It has the potential for improved collection of requirements, project integration as well as feedback and feedforward for clients and designers. This paper outlines attempts to improve design quality through innovations in programming methodology, presents a model of the programming process, assesses existing software used to manage project requirements, and describes new application software currently under development that empowers businesses to create on‐line user needs and analysis statements.

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PRODUCTIVITY AND PREDICTIVE AND ANALYTICAL TECHNIQUES

Select this Article		Enhancing Productivity in the AEC Industry through Application of Rights Management Kenyon D. Potter ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)73 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Enhancing productivity is a strategic objective of stakeholders in the architecture/engineering/construction (AEC) industry. However, the copyright of architectural works can hinder the reuse of designs and frequently necessitates independent creation of new designs. An opportunity for increased productivity is lost unless designs can be reused in whole or in part. The paper proposes the utilization of rights management as an approach to this problem. Given the AEC industry's structure and degree of sophistication, rights management would be the superior approach in the broader AEC industry. The paper describes a rights management system for implementation in the AEC industry that would assure certainty of copyright clearance from the rights holder(s) and the efficient licensing of designs for reuse on subsequent projects. Utilization of the described system would enable architects and engineers to reuse successful features of prior designs. In this way, application of rights management could enhance productivity in the AEC industry as it has in other industries that rely on creative works. The paper also addresses related issues including scope of permissions and potential liability relating to reuse of designs.

Select this Article		Predicting Schedule and Cost Elements' Variation for EPC Projects in Alberta Tanveer N. Ahmed, Janaka Y. Ruwanpura, and Ross Clark ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)74 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Planning and making advance decisions for an Engineering Procurement Construction (EPC) project is very critical because of the complexity of the project and the equal importance of major areas within engineering, procurement and construction. However, EPC projects, particularly in Alberta, have suffered from variances (or overruns) in cost and schedule in the last decade. Therefore, predicting an EPC project's outcome to a certain degree of accuracy in terms of cost and schedule, based on historic data, could add value to EPC business. The research presented in this paper has two objectives. First, it identifies areas of major influence to the final project cost by ranking the generic EPC schedule elements that have been developed by the Construction Industry Institute (CII). Second, it analyzes historical project information and shows the relationships between variances that may occur during the project's life cycle to predict the cost outcome of an EPC project.

Select this Article		Overmanning Impact on Construction Labor Productivity Awad S. Hanna, Chul‐Ki Chang, Jeffery A. Lackney, and Kenneth T. Sullivan ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)75 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract This paper details the impacts of overmanning on labor productivity for labor intensive trades, namely, mechanical and sheet metal contractors. Overmanning in this research is defined as an increase of the peak number of workers of the same trade over actual average manpower during project. The paper begins by reviewing the literature on the effects of overmanning on labor productivity. A survey was used to collect data from 54 mechanical and sheet metal projects located across the United States. Various statistical analysis techniques were performed to determine a quantitative relationship between overmanning and labor productivity, including the Stepwise Method, T‐Test, P‐Value Tests, Analysis of Variance, and Multiple Regression. The results indicate a 0% to 41% loss of productivity depending on the level of overmanning and the peak project manpower. Cross‐validation was performed to validate the final model. Finally, a case study is provided to demonstrate the application of the model.

Select this Article		Effect of Pre‐Construction Planning on Project Outcomes Cindy L. Menches, M.ASCE, Awad S. Hanna, M.ASCE, and Jeffrey S. Russell, M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)76 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Pre‐construction planning is gaining popularity as one approach to improving productivity in the construction industry. In the past decade, only a handful of studies have been completed on the project planning process; yet, most contractors believe better planning can lead to better outcomes and increased profitability. This paper describes an on‐going research project that attempts to (1) model the electrical pre‐construction planning process, (2) investigate the relationship between planning practices and project outcomes, (3) identify which planning practices lead to outstanding performance, and (4) establish metrics for evaluating planning effectiveness. Preliminary results and a detailed methodology for the final phase are presented.

Select this Article		Apportioning Concurrent Delays and Accelerations Using Daily Windows Kehui Zhang and Tarek Hegazy ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)77 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Project as‐built duration is the resultant of all day‐to‐day events and actions, including slowdowns, work stops, and accelerations, made by all project parties. In current practice, however, a systematic procedure for recording and analyzing daily actions is lacking, thus making the quantification and analysis of time‐related and cost‐related claims a complex task that is highly controversial. In this paper, a practical model is presented, with an analytical framework, for analyzing project as‐built schedules, considering slowdowns, work stops, and accelerations. The model differentiates between owner‐directed and contractor‐voluntary accelerations and deals with acceleration as a negative delay attributable to the party that creates it. To provide accurate and repeatable results, the model uses a daily windows analysis technique for apportioning concurrent delays and accelerations. Details of the proposed model are provided along with an example application. The model is readily usable by professionals and researchers to dynamically analyze the impact of all events along project duration.

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INDUSTRY ORGANIZATION AND PARTICIPANT ROLES

Select this Article		The Effects of the Informal Sector on Construction Carol Jewell, Roger Flanagan, and Keith Cattell ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)78 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Most construction sectors around the world have a high percentage of output being produced informally. In developing countries informal construction activities can account for as much as 80% of employment (Farrell 2004). In general, the informal sector equates to a significant percentage of country's GDP — 40% in developing countries and 18% in the OECD high‐income countries. The informal sector in construction is not well understood and difficult to measure and is thriving both in the developed and developing world. Construction industries are made up of a large number of small firms and a small number of large firms. Many small firms are less likely to be able (or to want to) afford the bureaucratic demands of a nation's fiscal and legal system. This evasion means a reduction in tax income for the government, and also leads to inaccurate estimates of the true value of construction output. Some national statistical agencies factor in an estimate of the size of the informal sector, but without effective measurement, there is no guarantee that the estimate is a fair one. The message from the paper is that the informal sector in construction is likely to grow. We need to understand the sector and recognise its impact on construction.

Select this Article		Source of Construction Industry Instability and Performance Problems Dean Kashiwagi, Kenneth T. Sullivan, David Greenwood, Jacob Kovell, and Charles Egbu ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)79 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract A ten year study of construction performance has resulted in a conclusion that construction industry performance problems are being caused by the client's delivery process. The hypothesis of the research is that the client has created a price‐based environment which forces a technical solution to construction issues. Modeling has been created which deductively shows that the problem is being caused by the client's selection of contractors rather than the type of delivery process (design‐bid‐build, design‐build, or CM@Risk). A solution is proposed in the paper which uses the concepts of outsourcing, quality control (rather than management and inspection), continuous improvement with minimal client control, and a process based upon leadership rather than management principles. One of the major design requirements for the process is that the client must receive best value (best performance at the lowest possible cost) and the contractor must maximize their profit. The deductive design is supported by test results over the past ten years.

Select this Article		High Performance Building Design Process Model Chris S. Magent, David R. Riley, and Michael J. Horman ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)80 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract High Performance “sustainable” or “green” buildings are emerging as an important market in the United States and around the world. The increased demand for high performance buildings has simultaneously created an opportunity to rethink the design process. To optimize the design process for high performance buildings, a project management environment that unites architects, engineers, and builders must be created and key design processes and competencies of design teams must be defined. This paper presents the initial results of an effort to model the process and discipline requirements for the design of high performance buildings. The Building Design Process Model for High Performance Buildings (BDPM^HP) and the accompanying Cross‐Functional Design Process Map for High Performance Buildings (CFDPM^HP) are presented as mechanisms to assist in the transformation of traditional design processes. Background and design development models of the BDPM^HP and CFDPM^HP are presented and testing of the BDPM^HP through case study analysis and virtual design team simulations is described. Emerging patterns and key processes on successful high‐performance building projects are identified. This research benefits facility owners by identifying key attributes of a high performance design process that decrease design process waste and reduce the first‐cost of high performance projects.

Select this Article		Design Management in Design and Build Projects: The New Role of the Contractor Edwin H. W. Chan, Albert P. C. Chan, and Ann T. W. Yu ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)81 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract The team members in Design and Build D&B projects, including owner's representative, contractor and architect/engineer, have to re‐adjust their traditional thinking and to learn extra professional skills to cope with the increasing complexities and demands of modern practice and for managing the design of large‐scale projects. In D&B contracts, the design responsibility is transferred from the owner's organization to that of the D&B contractor. This paper presents a study, which reviews the project management of D&B projects and also analyses the issues relating to design management process and design risk of the project participants with their changed roles. The study explores the performance and adaptability of the D&B contractor in design management. A questionnaire survey and structured interviews of three groups of project participants: owners, designers and contractors were carried out. The study results indicate that, though there are identified areas needing improvement, most of the respondents have satisfactory experiences with the D&B contractor's performance in terms of effectiveness in managing the design team, adequacy of design knowledge and their ability in managing the design process.

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KNOWLEDGE MANAGEMENT

Select this Article		Learning Organizations in Construction Paul Chinowsky and Keith Molenaar ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)82 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract The transformation of organizations from production oriented entities to proactive learning entities that continuously leverage the knowledge of the workforce is a primary objective of management researchers. This focus has significant relevance to the construction industry where production has overshadowed organization development since the inception of the industry. As one effort to change this emphasis, the authors present a research effort designed to study current organization learning techniques and technologies fielded by organizations both inside and outside of the construction industry. In addition to this analysis, the authors are developing a framework together with the Construction Industry Institute that provides construction organizations with a model for developing a learning organization culture. This paper introduces the results of that effort including a presentation of the learning organization framework, how the framework is used, and the overall characteristics of a learning organization.

Select this Article		Applying Context to Systems Integration in AEC Yimin Zhu ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)83 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Large‐scale capital programs, often involving many concurrent projects with huge amount of investment, multiple years of planning, design and construction and thus great social and economic impact, bear many features of dynamic, or ad‐hoc, collaboration mainly due to the fact that they have multiple, volatile yet collaborative organizations, as well as heterogeneous supporting information systems. In order to provide an integrated information base for decision support, many previous studies focused on a strategy of sharing a common semantic model among heterogeneous data sources. Such a strategy has many obvious benefits; however, it works only when it is possible for heterogeneous data sources to share the common semantic model. For collaborating systems that cannot share a common semantic model, a different strategy is needed. This paper, based on the theories and the principles developed in the computer science, discusses the concept of context and its potential applications to AEC (Architecture Engineering Construction)‐related systems integration, the dichotomy of semantics and context, and a conceptual solution of using context to assist systems integration. Limitations and future studies will also be discussed.

Select this Article		Enhancing Knowledge and Experience Exchange through Construction Map‐Based Knowledge Management System Yu‐Cheng Lin, Lung‐Chuang Wang, H. Ping Tserng, and Shu‐Hui Jan ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)84 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Knowledge Management (KM) has become an important term in the construction industry. Knowledge management involves creating, securing, capturing, coordinating, combining, retrieving and distributing knowledge. The knowledge can be reused and shared among the involved engineers and experts to improve the construction process and reduce the time and cost of solving problems. Sharing and reusing knowledge depends on acquiring and preserving both tacit knowledge and explicit knowledge as the property of a corporation. This study addresses application of knowledge management in the construction phase of construction projects and proposes a construction map‐based knowledge management (MBKM) concept and system for general contractors. This paper proposes a practical methodology to capture and represent construction project knowledge by using knowledge map. Using knowledge maps, users can get an overview of available and missing knowledge in core project areas and take appropriate management in tacit and explicit knowledge. Also, a portal system is developed to assist and present project‐related knowledge by providing keyword and map search. The MBKM system is then applied in a case study of a construction precast office building in Taiwan to verify our proposed methodology and demonstrate the effectiveness of sharing knowledge special in the construction phase. By effectively using information and web technologies during the construction phase of a project, knowledge can be captured and managed to benefit future projects. The combined results demonstrate that, an MBKM‐like system can be an effective tool for all experts and engineers participating for construction projects by utilizing the knowledge management concept and web technology.

Select this Article		Company‐Wide Project Data Integration for a Construction Organization Thammasak Rujirayanyong and Jonathan J. Shi ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)85 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract A construction company constantly generates a great amount of data that are distributed across various functional databases to support its daily operations. Those databases are typically maintained separately by responsible departments in the company. As a result, data sharing can be difficult between management functions. A decision‐making process may be slowed if data obtained from different sources conflict with each other. A central database which can collect data from existing databases is needed for providing timely access and quality of data for analyzing the business so that essential business decisions can be made appropriately and promptly. A data warehouse is the concept that collects all of the needed data into one system, organizes the data to be consistent and easy to read, keeps “old” data for historical analysis, and provides timely access. The unique nature of construction business is widely recognized. A central database model must reflect the nature of the construction business. This article presents a project‐oriented data warehouse structure and the implementation of a prototype in a typical construction firm.

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CONTRACTING ALTERNATIVES

Select this Article		Contracts: A Holistic Perspective Michael S. Puddicombe ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)86 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract In a lengthy editorial in ASCE News (2004) Patricia Galloway, P.E. calls for engineers to “lead the way” in the development of engineering and construction contracts. She notes that a significant portion of the problems that occur in projects today relate to management issues that result from “a failure to understand the basic tool that governs all projects…. the contract.” In discussing these issues, engagement with the legal profession is seen as a critical step towards this leadership position. This paper argues that indeed the contract is a key component of all projects, however the understanding required goes beyond that which is encompassed in a legalistic perspectives. Contracts define the playing field upon which the project evolves bringing economic and social‐psychological issues into play. Understanding contracts require an understanding of these forces.

Select this Article		Dispute Resolution Transactional Cost Quantification: What Does Resolving a Construction Dispute Really Cost? Richard J. Gebken, II, G. Edward Gibson, P.E., and James P. Groton ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)87 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract The construction industry is generally acknowledged as the world's most litigious industry with one industry study citing nearly $5 billion in annual expenses on litigation and arbitration in the United States alone. Yet at the same time, the construction industry has been a champion for creating and implementing innovative new techniques for preventing, controlling, managing and amicably resolving disputes for many years. As a result, the construction industry has available to it a wide spectrum of dispute‐management methods. Despite these options, no empirical data exists on the transactional costs for resolving disputes throughout the full spectrum of dispute resolution techniques. Inevitably, resolving a dispute costs all parties money, not just the amounts paid to settle the dispute, but also the “transaction cost” of processing the dispute: lawyer fees, experts' fees, management time, etc. This paper explores a procedure for quantifying transactional costs in various dispute resolution techniques and explains how transactional cost information can be used as a dispute‐management selection tool. Data from 26 projects, with total installed costs over $850 million USD, are presented to illustrate information on the transactional costs associated with different methods of dispute resolution from an ongoing research study at the University of Texas at Austin.

Select this Article		Statistical Comparison of Performance Based Procurement and Price Based Procurement Darshit Parmar, Kenneth Sullivan, Charles Egbu, David Greenwood, and Dean Kashiwagi ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)88 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Performance based procurement is a relatively new directive for contractor selection. Performance based procurement considers the value of the contractor's services in the award of the contract in addition to the submitted bid price. This study utilizes a statistical analysis comparing the abilities of the performance based and price based (lump sum low‐bid) procurement processes to deliver project performance, to minimize the risks of the schedule, to minimize the risks of the budget, and in not meeting the client's expectations. The study also uses the results of statistical tests to identify the relative first costs of the processes and the client's management and control responsibilities. The results of the study show that a performance based procurement process delivers higher performance, minimizes subjective decision making, minimizes risk, and that cost and performance may have no direct relationship.

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INFRASTRUCTURE PROJECT DELIVERY SYSTEMS

Select this Article		Use of Design‐Build on Mass Transit Rail Projects John E. Schaufelberger ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)89 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract While the design‐build delivery method has been used successfully on many types of projects, its application to mass transit rail projects has produced mixed results. In an effort to determine the reasons for this, a study was undertaken to evaluate the use of the design‐build delivery method on large mass transit rail projects in the United States. The objective of the study was to analyze the New Starts process used by the Federal Transit Administration. Eight design‐build mass transit rail projects were analyzed to determine if revisions could be identified that would facilitate the use of a design‐build delivery process. Questionnaires were sent to the three primary stakeholders for each project to collect data regarding how the project was administered and the outcome achieved. Analysis of the data indicate that two useful changes to the New Starts process would be: (1) the timing of the procurement of the design‐build contractor and (2) timely assurance of the availability of federal funds.

Select this Article		Delivering Highway Projects through Design‐Build: Analysis of the Comprehensive Development Agreement (CDA) Procurement Process in Texas Giovanni C. Migliaccio, G. Edward Gibson, Jr., and James T. O'Connor ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)90 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Design‐Build (D‐B) has been increasingly adopted for construction projects in the United States. Previous research has identified the desire to reduce the total project delivery time as the primary reason to select D‐B. However, inexperience of state transportation departments (STD) with D‐B can slow the procurement phase, endangering the desired time reduction. Therefore, the knowledge of the activities to be included in a D‐B procurement process and their critical sequencing is a central issue in conducting projects under D‐B. Although many recent studies focused on the evaluation aspect of the procurement, much less attention has been paid to the sequencing of activities to be performed by a STD between the “go/no go” decision and the contract execution. This paper summarizes the findings from research analyzing the procurement of two D‐B projects in Texas: State Highway 130 (SH130), and the State Highway 45 Southeast (SH45 SE). Using the lessons learned from these ongoing projects, the researchers have developed a streamlined D‐B prourement process for delivering highway projects.

Select this Article		Risk Management on Build‐Operate‐Transfer Projects John E. Schaufelberger ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)91 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract The build‐operate‐transfer (BOT) method of developing public infrastructure has been used for many projects in Asia. Unfortunately, about 30% of the BOT projects have had disappointing results. In undertaking such projects, the private sector incurs significant risks that must be understood and managed for such projects to be successful. This paper reports the results of a study of seven Asian BOT projects undertaken to determine the primary risks the project sponsor faced, the risk management strategies that were selected, and the results obtained. Two major categories of risk were identified, general risks and project‐specific risks. From this analysis, a risk management framework was developed for each category of risk. The results of this study indicate that the private sector cannot be the only participant in risk management, but that the host government's active support is essential to have a viable BOT project in Asia.

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INFRASTRUCTURE PROJECT COST MANAGEMENT

Select this Article		Preliminary Cost Estimates Using Probabilistic Simulation for Highway Bridge Replacement Projects Jui‐Sheng Chou, Linlin Wang, Wai Kiong Chong, and James T. O'Connor ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)92 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract To improve the accuracy and efficiency of highway budgeting estimation has been an important research focus in the industry and is the objective of this paper. Useful data were extracted from the Texas Department of Transportation (TxDOT) to develop an alternative to achieve the research objective. Heuristic simulation models pertaining to highway bridge replacement projects were developed to guide engineers to reduce estimation variability before the beginning of planning authorization. The proposed simulation models include independent, correlated, and Latin Hypercube sampling approaches that specifically consider major work items, roll‐up work items, and project‐level engineering contingency. The charts of cumulative density functions (CDFs) are derived as a handy tool for decision makers to consider project finance initiation, project risk and uncertainty assessment. The systematic procedure can be expanded to other project types and to develop lane‐km (lane‐mile) cost distributions when ample historical project data are available.

Select this Article		Design Cost Analysis of Transportation Projects Khaled M. Nassar, Mohamed Y. Hegab, and Nicholas W. Jack ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)93 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Transportation projects are usually designed in three phases: phase I is the preliminary design report, phase II involves the preparation of the actual construction documents including plans and specifications, and phase III involves the construction inspection and contract administration of the project. The process of arriving at total design man‐hours and the related design costs is often the most contentious and difficult part of phase II for both the consultant and the STA (State Transportation Agency). The main objective of this research is to model the design costs of consultant designed projects. Actual data were collected from The Illinois Department of Transportation (IDOT). Statistical modeling techniques were used to predict the design costs. The models developed in the following pages will help supplement the current methods of estimating design costs currently used by IDOT. Currently the Illinois Department of Transportation maintains a set of manuals used by the Bureau of Design and Environment for guiding engineers through the design phase for highway projects. These manuals are very comprehensive covering all facets of the design process. The models contained in this research could be implemented in the Design and Environment manuals.

Select this Article		Construction Project Cost Performance Prediction Based on Project Bid Characteristics J. A. Kuprenas ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)94 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents the results of a series of regression analyses of a data set of two dozen completed public sector projects procured using the traditional public contracting code low bid process. All projects are from the same multi‐billion dollar school construction program and have been completed in the last two years. The work correlates construction cost performance measured through change orders (as a percentage of bid value) against the bid characteristics of the same project, measured as: (1) Bid (as a % of Bid Budget), (2) Number of bidders, (3) Bid Date, (4) Date since last bid, (5) Bid Cost per Square Foot, (6) Bid Amount ($). Based on the results of these analyses, conclusions to the paper suggest project success factors / guidelines for future bids within this program in order to improve bid / construction cost performance. The paper also includes suggestions for future research, particularly in the areas of follow up work as additional data becomes available and expansion of this research to include construction schedule and quality performance measures.

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INFRASTRUCTURE PROJECT SCHEDULING AND OPTIMIZATION

Select this Article		Priority Scheduling of Urban Rehabilitation Streets to Minimize Congestion, Delays, and Accidents Wesley C. Zech and Satish Mohan ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)95 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract This paper describes the framework of a priority scheduling algorithm that minimizes traffic congestion, travel delays, and accidents that occur during the rehabilitation of urban streets. The process utilizes: (i) GIS technology for storing and visualizing the necessary data of streets, and for applying traffic assignment, (ii) previous research on the costs of congestion, travel delays, and accident rates, and (iii) utility theory for combining the values of the qualitative and quantitative attributes associated with road rehabilitation. The priority scheduling framework, developed in the research, has been applied to an example town with a population of 116,000, in which 10 street links were selected for repaving in 3 time phases, each of two months, during one construction season. By comparing the multi‐attribute utilities of the three attributes using the proposed priority schedule, against the average multi‐attribute utilities of 10 random time‐schedules of the 10 streets (standard practice), the proposed construction scheduling algorithm yields a saving of 13 veh‐hrs/hr in network travel time, $127/hr in the cost of comfort and convenience, and 11 accidents per year. Further research is required for coding the proposed algorithm into an expert system that practitioners can easily learn to use and draw priority schedules for their road rehabilitation programs.

Select this Article		Use of Conceptual Road User Costs for a Rapid Roadway Construction Decision Making System Yinggang Wang and Paul M. Goodrum ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)96 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract This paper outlines a decision making system, for the use of rapid roadway construction methods using conceptual road user costs (RUC). The research developed a series of RUC tables that reflect different socioeconomic conditions by varying the value of time based on average hourly per capita income and wages for different counties in Kentucky. The RUC tables are established to address different types of highway projects (four‐lane, six‐lane), various topographical conditions (level, rolling and mountain) and construction schedule (daytime, night and overtime). Determining RUC by this method simplifies the method of calculating RUC by using fewer variables that would typically be available during the preliminary and conceptual design stage. The project's intent of determining conceptual road user costs is to support a decision making process to identify the need and type of rapid construction method for a particular project. A specific decision making process is proposed, which uses the ratios of the Calculated Road User Cost (CRUC) to the Maximum Allowable Road User Cost (MARC) followed by a set of additional criteria based on project scope to recommend a selection of rapid construction methods for a given highway project.

Select this Article		Accelerated Pavement Rehabilitation on Urban Highways: Innovative Approach in California Eul‐Bum Lee, Michael Samadian, and Hojung Lee ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)97 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Pavement renewal for urban highways is a critical issue confronting the California Department of Transportation (Caltrans) as large portions of its highway system have exceeded their original 20‐year design lives and are in need of rehabilitation and reconstruction. This paper introduces the innovative pavement renewal technologies and techniques that Caltrans has developed and/or adapted under the “Get In, Get Out, and Stay Out” approach emphasizing a rapid, long‐lived renewal of urban highway pavements with minimized traffic impacts. Experimental projects where the effectiveness of these technologies and techniques were validated are discussed. Also introduced in the paper is the integrated analysis process combining pavement design, construction logistics, and traffic operations that Caltrans applied in its latest experimental highway project. CA4PRS (Construction Analysis for Pavement Rehabilitation Strategies) software was used as an analysis tool in the integrated process. Caltrans expects that this integrated analysis process will better ensure the selection of optimum rehabilitation strategies reflecting given project conditions to effectively reduce costs to transportation agencies and highway users. It is expected that the positive results and lessons learned from testing these technologies and techniques on the experimental projects cited will lead to the expanded application of the “Get In, Get Out, and Stay Out” approach in future urban highway rehabilitation projects in California. The issues and outcomes discussed in this paper will be beneficial to other transportation agencies and contractors in maximizing rehabilitation productivity, minimizing agency and user delay costs, and achieving long‐life performance in urban highway rehabilitations.

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INFRASTRUCTURE PROJECT STRATEGIES

Select this Article		Real Options Analysis: Can It Improve Infrastructure Development Decisions? Michael J. Garvin ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)98 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Increasingly, infrastructure owners worldwide are turning to the private sector to help finance needed infrastructure expansion and modernization. BOT arrangements are one mechanism for utilizing private capital for public purpose, but frequently, these projects possess managerial options, which are not directly valued by either the government or the private concessionaire because conventional valuation methods fail to capture flexibility's value. Real options analysis (ROA) has emerged over roughly the last two decades to address this limitation. Four prevailing ROA methods, which are briefly described, have surfaced from the related but independent fields of finance and decision theory, but application of these techniques to infrastructure projects remains problematic. Specifically, their assumptions and mechanics appear to limit their value to the infrastructure community. These circumstances have motivated an ongoing research program to assess the utility of ROA methods during infrastructure development decisions. A case study of the Dulles Greenway provides a forum for: (a) discussing the research program's objectives and methods, (b) illustrating the classic and the marketed asset disclaimer (MAD) approaches to value a deferment option embedded within the project, and (c) providing a preliminary assessment of whether ROA is a promising complement to traditional project analysis methods. The provisional conclusions are that ROA methods are promising for both strategic insights and credible valuation.

Select this Article		Multi‐Objective Optimization for the Construction of Large‐Scale Infrastructure Systems Amr Kandil and Khaled El‐Rayes ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)99 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents the development of an advanced Information Technology Framework for Optimizing Construction Utilization of Resources in Civil Infrastructure Systems, named IT‐FOCUS. The main objectives of this framework are to: (1) develop robust optimization models for minimizing construction cost, and duration, while maximizing quality; and (2) formulate scalable methodologies for solving large‐scale construction optimization problems. To this end, the present framework is implemented using an advanced multi‐objective genetic algorithm that is capable of generating optimal trade‐offs between construction cost, duration, and quality. To enable the optimization of large‐scale infrastructure projects, the algorithm is parallelized using the manager‐worker paradigm of parallel and distributed computing. The parallel implementation of the algorithm utilizes the message passing interface (MPI) standard to distribute genetic algorithm computations over a cluster of 50 Intel Xeon processors. A number of large‐scale construction projects with sizes ranging from 180 to 720 activities were evaluated using the 50 processor cluster to evaluate the computational requirements for optimizing real‐life construction projects. The results of this evaluation highlight the significant computational savings that can be achieved by the implemented parallel computing framework.

Select this Article		Developing Best Practices for Avoiding Utility Relocation Delays Ralph D. Ellis, Jr., M.ASCE and Seung‐hyun Lee, M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)100 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Much progress has been made with regard to improving the precision of subsurface utility location. Recent advances in Subsurface Utility Engineering (SUE) technology have significantly improved the quality of utility — project design interface. However, utility related delays remain the leading cause of highway construction project delays. Obtaining quality utility location information is obviously important. However this does not address the entire utility delay issue. A significant portion of the utility related delays occur because of delays in relocation activities. A major part of the difficulty appears to be related to the fact that the utility activities are often not a direct part of the highway construction contract. Utilities typically occupy State Highway Agency (SHA) right of way space with some form of lease agreement. Obtaining the required relocations on schedule is problematic. However, some SHAs are making progress in developing innovative contractual and procedural practices to facilitate on time utility relocations. This paper will present the results of a recent study to identify the current best practices of SHAs and other organizations for managing utility relocation. Innovative contracting practices involving the restructuring of the traditional relocation process will be explored. Details of the best practices will be synthesized and presented.

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SIMULATION APPLICATIONS FOR INFRASTRUCTURE PROJECTS

Select this Article		RoadSim: Simulation Modelling and Visualisation in Road Construction Serafim Castro and Nashwan Dawood ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)101 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Road construction is an equipment‐intensive process and its planning and management are essentially different from methods usually adopted for other construction activities. This is essentially due to: the very high value of road contracts; the very high cost of inputs (equipment and materials); the physical extension of works; the sensitiveness of works to meteorological factors; the environmental impacts and potential conflicts with other social and economic activities. Current practices in the industry suggested that road construction planning is inefficient and projects are often over budget and time. Moreover efficiency gains may only be obtained with the introduction of new and more innovative tools to assist managers in planning and managing road construction projects in order to construct projects on time and on budget. The tools should be able to assist managers to study and compare all possible strategies and methodologies for the execution of the works and ensure that the planner's choice corresponds to the most advantageous possibility. To overcome the limitation faced by traditional planning tools and automate the road construction planning process a computer‐based simulation system has been developed. The system is designated RoadSim and the respective framework is described in this paper.

Select this Article		Simulation Tools for the Economic Evaluation of Base Construction Jaehyun Choi, R. Edward Minchin, Jr., and Zohar J. Herbsman ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)102 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract The Florida Department of Transportation (FDOT), for the majority of its highway projects, specifies base option group(s) from which successful bidders must choose. Each group contains several options of material types with corresponding thicknesses. Among the several options, the choice usually comes down to an aggregate (usually limerock) base or a hot‐mix asphalt (HMA) base. In the past, deciding which alternative method to use was typically based on a direct cost comparison derived from unit prices of materials, labor, and equipment. When using only this direct cost parameter, the limerock alternative almost always appears to be the most cost‐effective. However, when interviewed, many FDOT practitioners felt that other parameters should be taken into consideration when calculating the true costs of both options and determining the best alternative. Often, the researcher or practitioner knows the cost and construction duration of one of the options, but not the others. The need for such information on all options led to the development of the Structural Number Method (SNM). Using the SNM, base construction using the alternative method(s) may be simulated. To expedite the process of simulation, a computer‐based simulation model was generated that will simulate the construction of bases using materials whose cost and duration are known—and those for which this information is not available. The model will then render an opinion as to which method should be used. This model is known as the base economic analysis tool (BEAT). This paper introduces the BEAT and the SNM, two innovations to productivity and cost analysis in the area of highway base construction and explains what circumstances caused the much less‐expensive material to sometimes have the higher total cost.

Select this Article		A Study of Simulation‐Based Contract Incentives and Disincentives Usage Ralph D. Ellis and Jae‐Ho Pyeon ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)103 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract A simulation‐based method of using Incentives and Disincentives (I/D) contracting in highway construction projects is presented. Providing guidance in a proper use of I/D contract methods, the present model improves the efficiency of I/D contracting in highway construction projects. Data analysis is performed for the application of I/D contracting to construction contracts. Using statistical analysis, influencing factors in I/D contracting are identified. Monte Carlo simulations are then performed in case studies for the purpose of model validation. The present model can serve as a tool for owners and managers to make a decision in use of I/D contract in highway construction projects.

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INFRASTRUCTURE VI

Select this Article		Identifying Factors for Statistical Models to Measure Highway Project Disruptions Wai Kiong Chong, Jui‐sheng Chou, and Sang‐Hoon Lee ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)104 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Highway projects are thought to be influenced by many different types of delays. Data collected from twenty‐eight Texas highway projects over a two year period found that utilities conflicts, rain and shortage of materials are the only three significant disruptions. Research also found that most of the disruptions caused production to stop between one to five days while few had stoppages of more than ten days. This paper also found that productivity recovery from different types of delays was different and that learning effects had huge impact on the rate of recovery. The research identified several useful factors that could be used to develop statistical models to estimate delays on reinforced concrete pipes. First, rain related productivity delays could be estimated by differentiating clay content in soil. Second, utilities conflicts could be estimated by differentiating the types of utilities that were involved. Finally, the actions that were taken by the contractors could be used as factors to measure productivity recovery. The overall project delays could be estimated using these factors. These factors were also found to be extremely useful to resolute disputes on time claims due to disruptions.

Select this Article		Building Underground: Special Techniques for a Storage Facility Ioannis E. Zevgolis ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)105 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Underground construction in metropolitan cities around the world has been steadily gaining ground during the last decades. This is due to a series of reasons, among them the lack of sufficient surface space and the increased cost of surface land. Athens, the capital of Greece, with a population density of 8,000 inhabitants/km² and with the vast majority of the country's commercial, industrial, and business activities gathered within its boundaries, is not an exception to these cities. One of the business sectors that suffer from the scarcity of surface space is that of warehousing and logistics. The demand for new storage facilities increases, whereas the capacity of surface areas to host them is already exceeded. Urban planners tend towards innovative solutions that will alleviate the problem. Subsurface space utilization is regarded as one of them. Within this frame, a research project was recently carried out in order to examine the feasibility of an underground warehouse in the area of Athens. In this paper the engineering construction and management issues of the project are discussed. The construction of the warehouse is divided in two phases. First, the underground space is created using mining techniques. Second, the already excavated space is converted into a state‐of‐the‐art facility, following the standards of typical surface warehouses. Although the two phases have different characteristics, they are planned to advance in parallel, with the second one occupying the areas already mined out. The room and pillar method is adapted from mining for the space development. Excavation takes place in two stages, using the drill and blast technique. Construction is anticipated to last about two years. At the end of this period, the space will be ready for commercial use.

Select this Article		Testing RAP Materials for Overlay Design Standards Rafiqul A. Tarefder, Musharraf M. Zaman, and Cheong F. Ting ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)106 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Cold‐mixed, cold‐laid (CMCL) rehabilitation or cold recycling is a technically promising and cost effective method for improving distressed asphalt pavements. Unlike hot mix recycling, cold recycling lacks field and laboratory performance data. Also, there is no widely accepted CMCL design and testing standards available. This study has generated useful field and laboratory data on pavement overlay constructed with 100% recycled asphalt pavement (RAP) and the CMCL technique. The laboratory tests conducted in this study include physical property, strength and performance‐related tests. While property tests include moisture content, gradation, specific gravity, emulsion content, aggregate properties, coating and adhesion; strength and performance tests include resistance, indirect tensile strength, moisture‐induced damage susceptibility, and rutting. In addition, two field case studies are conducted; one overlay job was quite successful but the other exhibited relatively poor performance. Causes of differential performance are examined.

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DATA ACQUISITION WITH SENSOR TECHNOLOGIES

Select this Article		Experiments in Real‐Time Spatial Data Acquisition for Obstacle Detection Jochen Teizer, Katherine A. Liapi, Carlos H. Caldas, and Carl T. Haas ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)107 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Rapid spatial data collection is desirable for many applications in engineering and construction. Recent technology developments such as Flash LADAR devices (Laser Detection and Ranging) allow rapid acquisition of range and intensity scene data. Methods that process the ouput into 3D side models and display or provide the location of objects on a site significantly improve work processes. A particularly useful application is modeling the presence of obstacles in structured or unstructured construction‐type scenes including people, material, and equipment. The development of obstacle avoidance systems improves safety during the operation of equipment and efficiency for picking and placing objects. This paper describes laboratory experiments and field trials under realistic conditions for the development of obstacle detection algorithms for construction machinery using a high frame‐rate Flash LADAR sensor. The focus is on the acquisition of experimental data to determine the benefits and limitations of this approach within the construction industry. Tests were conducted to analyze and discuss the sensor performance and evaluate the trade‐off between scene detail and processing speed. Future research goals are in the development of algorithms allowing accurate scene modeling by acquiring data from a moving object and detecting both stationary and moving obstacles in the motion path.

Select this Article		Locating Materials on Construction Site Using Proximity Techniques Jongchul Song, Carl Haas, Carlos Caldas, and Katherine Liapi ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)108 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Construction materials and installed equipment comprise 50–60% of the total cost of a typical industrial project. Tracking the location of construction resources automatically should both improve project performance and enable effortless derivation of performance indicators such as productivity. With recent advances in automated data collection technologies, tracking the location of materials on site has become more viable. A central issue in using these technologies for this purpose is that the existing approaches imply economically prohibitive deployment. This paper presents an approach by which a combination of RFID and GPS technologies may offer the opportunity to densely deploy RFID tags with a few mobile RFID readers equipped with GPS to form the backbone of a construction materials' tracking system. The findings from preliminary experiments suggest that using this approach, RFID technology may be technically feasible in determining the 2D and ultimately the 3D location of materials on site, when combined with GPS technology. The solution proposed here is intended to extend the use of current RFID technology to tracking the precise movement and location of materials on site, without modifications to current hardware and at a magnitude less cost than pure GPS or other existing approaches.

Select this Article		Technology and Process Assessment of Using LADAR and Embedded Sensing for Construction Quality Control Chris Gordon and Burcu Akinci ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)109 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Emerging LADAR and embedded sensing technologies are making inroads into the construction industry for quality control applications. Much of the research conducted and the practical usage to date have focused on a static snapshot evaluation of already constructed structures. A remaining question is how technologically feasible and applicable these technologies are for frequent inspection during construction. Researchers in the civil engineering, architecture, and robotics departments at Carnegie Mellon University are developing and evaluating a formalism for application of these technologies for supporting quality control on construction sites. This formalism consists of developing a formalism for planning inspections, collecting data, modeling as‐built conditions, and reasoning with the as‐built and as‐designed models to detect deviations and defects on construction sites. A series of five case studies on commercial and light industrial construction sites were conducted within the context of that research to identify challenges and opportunities in using LADAR and embedded sensing technologies to support inspection and quality control processes on construction sites. Based on the experiences in these case studies, the authors present a technology and process assessment of the use of LADAR and embedded sensing frequently to support inspection and quality control on construction sites.

Select this Article		Integration of Construction Field Data and Geotechnical Analyses Yun Y. Su, Jose N. Oliveira Filho, Liang Y. Liu, and Youssef M. A. Hashash ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)110 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Urban excavation includes complex engineering issues such as construction methods, support systems, base stability, ground deformations, groundwater control, and influence on adjacent structures. Additionally, the expansion of urbanization over the years has been generating an increasing demand for underground space. Open cuts and tunnels have long been used to create such urban underground space, but as the demand for underground space grows, those excavation issues become even greater concerns. One of the greatest concerns when constructing underground space, beyond conducting it in a timely and cost effective manner while maintaining a safe environment onsite, is the impact of ground movements related to construction activities. This paper presents the preliminary results of a research project which utilizes 3D laser scanning technology to provide accurate 3D as‐built construction data for geotechnical analyses. Funded by NSF, this project explores the integration of construction field data into geotechnical monitoring and forecasting that may potentially reduce the impacts of urban deep excavations. The accurate 3D geometry data and construction sequences provide new possibilities for geotechnical analyses at a higher precision.

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KNOWLEDGE REPRESENTATION

Select this Article		Hierarchical Clustering for Interpretation of Spatial Configuration Asad H. Udaipurwala and Alan D. Russell ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)111 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Ever since the introduction of computers—particularly the field of Artificial Intelligence—construction researchers have endeavored to develop systems that capture and encode the knowledge of seasoned construction practitioners with the goal of at least partially automating tasks such as construction methods selection, equipment selection, constructability reasoning and cost estimation. However, efforts to address these tasks to date have suffered from the lack of a mechanism for automatically inferring conditions such as uniformity/similarity in a facility's spatial configuration. Identifying these conditions is crucial for evaluating the suitability of a construction method as they affect criteria such as reuse and achievable production rates. In the absence of such a mechanism researchers have relied on either statistical techniques that can be biased by outliers, or simply put the onus on the user by querying them about the number of reuses, etc. which undermines the usefulness of the system itself. In this paper, we introduce an algorithmic technique based on hierarchical clustering that can be used to infer the similarity of part or all of a construction facility with respect to any measure of interest—such as length, area, volume, and so on. The advantage of this technique is that it is immune to outliers in the data set, and it can accommodate the intuitive notion of acceptable variability. For example, in an expert's judgment, a six percent variability in the dimensions of slab‐bays is acceptable for use of flying truss formwork as it can be accommodated with infill panels or hinge panels. We start by providing a motivating example from the domain of building construction, and illustrate how the techniques adopted by researchers to date fail in the case of various spatial configurations. We then provide the hierarchical clustering algorithm in detail after a short discussion of our technique for representing the project's physical context. Finally, we illustrate how the algorithm has been integrated with a project management system that provides a hierarchical representation of the physical view of a facility, and a production rule based expert system to aid in the selection of construction methods.

Select this Article		A Conceptual Framework for Mapping Data Representation in the AEC Domain Ivan Mutis, Raja R. A. Issa, and Ian Flood ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)112 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract There is a need in the construction industry to develop strong interaction between customers, contractors, and owners, using emerging technologies to facilitate communication and collaborative use of project information. A successful implementation of these technologies enables integration of project information based on real time and transparent information transfers to make decisions or to work on concurrent engineering. New approaches using data representation standards, which allow stakeholders' computer systems to exchange information between actors, have been used for the implementation of this integration. However, the main obstacle in enabling integration of the data representation is the matching process involved in tying data together. This process is complex but it is the ‘glue’ of the integration process and is very critical in making the exchange of information possible. This research is intended to develop new approaches for data representations in the construction domain to facilitate the mapping process between stakeholders. The research will determine the main characteristics of the data representations needed to perform matching operations in order to formulate alternative solutions and expedite the information exchange process. The proposed approach uses schema‐matching prototypes. The result of this approach is to produce a framework that contains an analysis of the typical data representation of the actors in the construction domain.

Select this Article		Application of Tolerance Mapping in AEC Systems Colin Milberg and Iris D. Tommelein ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)113 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Tolerance maps are a tool for specifying, analyzing and allocating tolerances for both product and process design. This paper introduces the authors' tolerance mapping system and the steps for creating and implementing the system to an existing design for evaluation and improvement, via a sample case. The paper addresses current industry limitations on tolerances, future mapping improvements and mapping implementation challenges.

Select this Article		A Usability Study of an Object‐Oriented Design and Specification System for Transportation Projects Russell C. Walters, Zhili Gao, Edward J. Jaselskis, and Manop Kaewmoracharoen ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)114 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Currently, individuals learn about the project requirements by studying a combination of paper and electronic copies of various construction documents. This can be a tedious process since one needs to go back and forth between documents to obtain information about the entire project. This study utilizes the object‐oriented computer‐aided design (OO‐CAD) technology to turn paper‐based design standards and construction specifications into an object‐oriented design and specification (OODAS) system. Individuals can use the system through a handheld wireless book‐size laptop that includes all of the necessary software for operating in a 3D environment. All parties involved in transportation projects can access all of the standards and requirements simultaneously using a 3D graphical interface. An OODAS prototype model was created and demonstrated to potential users representing counties, cities, and the state. Findings suggest that a system like this could improve productivity to find information by as much as 75% and provide a greater sense of confidence that all relevant information had been identified. It was also apparent that this system would be used by more people in construction than in design. There was also concern related to the cost to develop and maintain the complete system. The future direction should focus on a project‐based system that can help the contractors and DOT inspectors find information more rapidly as it pertains to a specific project.

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KNOWLEDGE MANAGEMENT

Select this Article		Development of Knowledge Document Management System (KDMS) for Sharing Construction Technical Documents Tai Sik Lee, Dong Wook Lee, and Sang Bok Jee ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)115 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract This study was executed in order to develop a construction technology information system. This system is capable of efficient information storage, search, and share. The “Knowledge Document Management System (KDMS)” developed in this study stores the knowledge on a server and enables management of the information by various access systems. The KDM explorer function and file browser can manage personal files, and users are able to achieve flexible knowledge management through a file viewer and preview function. In addition, the content‐based search function provides a word‐highlighted simple search. The KDMS can be helpful in managing mass technical information by each project, and search information considering the characteristics of construction technological information.

Select this Article		Canadian Construction Claim Tracker: An Integrated Repository System for Canadian Case‐Law Construction Claims Amir Chehayeb, S.M.ASCE and Mohamed Al‐Hussein, M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)116 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Construction contracts are becoming progressively more complicated; the increase in complexity of construction processes, documents, and conditions of contracts have contributed to a higher possibility of disputes, conflicting interpretations, and adversarial attitudes. Both the public and private sector have been looking to the judicial system as the means for dispute resolution for claims that cannot be solved through the other means of resolutions such as negotiations and arbitration. This paper presents a methodology to classify and categorize Canadian case‐law construction claims. A wide range of construction claims are collected from 10 different sources and are classified into 12 categories that follows the Canadian Construction Documents Committee (CCDC 2‐1994) standard contract document. To further identify specific causes of a claim, the 12 categories were divided into 32 subcategories. 567 Canadian construction claims have been collected; 460 ‘limited claims’ provide basic claim information and 107 ‘detailed claims’ provide detailed information used to analyze the collected claims. The proposed methodology for collecting and classifying the cases is implemented in a computer‐integrated system called the Canadian Construction Claim tracker (CCCT) that consists of one central database and three modules: a statistical module, a prediction module and a classification module. CCCT provides its users with easier and quicker access to past case‐law claim information.

Select this Article		Towards a Framework for Managing Standards‐Based Semantic E‐Resources in the European Construction Industry Celson Lima, Graham Storer, Alain Zarli, and C. Ferreira da Silva ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)117 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents the current status of the FUNSIEC project, which is a feasibility project that aims at evaluating the potential use of Semantic Resources (SRs) in e‐business matters, through the development of the Open Semantic Infrastructure for the European Construction Sector (OSIECS). This infrastructure is designed within the scope of the FUNSIEC framework. The requirements of OSIECS are identified, the SRs to compose OSIECS are selected, the OSIECS Meta‐schema/Schema are created through the application of mapping techniques to the respective Meta‐schemas/Schemas of the selected SRs, the conceptual architecture of OSIECS is designed, and the preliminary picture of the OSIECS infrastructure is drawn. This work discusses all these topics.

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COMPUTER‐AIDED DESIGN

Select this Article		Automated Construction Planning for Multi‐Story Buildings Tang‐Hung Nguyen ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)118 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract This paper outlines a computer‐based framework that can assist construction planners and schedulers in automatically generating sequences of construction activities to be required for the planning of a multi‐story building. This framework employs the concept of three‐dimensional solid modeling for representing building components enabling extraction of geometric data necessary for deduction of spatial relationships between the building components. These relationships include information about the intersection, adjacency, containment, and separation among building spaces and/or components. The deduced spatial information then can be used to generate building zones in a multi‐story building as well as construction activities to be performed in each zone. Automated methods to generate the building zones and construction sequences will be discussed.

Select this Article		Case Study of Constructability Reasoning in MEP Coordination A. Reza Tabesh and Sheryl Staub‐French ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)119 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Building system coordination is a complicated process that requires the detailed layout and configuration of the various building systems such that it complies with design, construction, and operations criteria. Current practice involves an iterative process of sequentially overlaying transparent 2D drawings of each system over a light table to identify potential conflicts and constraints, which is a time‐consuming and error‐prone process. Recent research efforts have focused on the development of knowledge‐based systems to further assist this coordination process. The objectives of this research were to collect and classify data on constructability knowledge utilized as part of a 3D MEP coordination process during design and construction of a complex research facility. We worked with the project team to develop detailed 3D models of all the building systems in several critical spaces. We identified the design and construction knowledge utilized to coordinate these 3D models and classified this knowledge in a multi‐variable knowledge framework. The representational framework, 3D modeling process, and modeling constraints are discussed.

Select this Article		Cost Estimating in the Age of 3‐D CAD Software and Object Databases Saeed Karshenas, M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)120 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Cost estimating is a vital activity for contractors. An estimate is not only necessary for proposal preparation but also for several project management functions. Despite the importance of estimating, it has remained a very time consuming process. The most inefficient part of construction cost estimating is determination of the amount of resources needed for the construction of a project—also known as quantity takeoff. The quantity takeoff process is still very slow, is not very accurate, and does not eliminate the possibility of an estimator missing or duplicating estimating items. New parametric CAD software is revolutionizing the way architects design buildings and will significantly increase construction cost estimator productivity by substantially reducing the manual work necessary for performing quantity takeoff. The data model of parametric CAD software allows easy exchange of building design information among various software systems used during design, construction and service life of projects. This paper discusses the architecture of an object‐oriented estimating system that eliminates the need for manual quantity takeoff by obtaining the necessary building element dimensions and properties from the project CAD model. The paper explains how Autodesk Revit parametric CAD software exposes project information and the class diagram of an object‐oriented estimating system that performs quantity takeoff by obtaining project information from building models prepared using Revit. The paper uses an object‐oriented database for persistence of estimating objects and discusses the advantages of object databases over relational databases for applications with a complex information model.

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VIRTUAL AND AUGMENTED REALITY

Select this Article		Heavy Equipment Operator Training via Virtual Modeling Technologies Xiangyu Wang and Phillip S. Dunston ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)121 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Off‐site and on‐the‐job training programs constitute current methods to train construction equipment operators. Being time‐intensive, expensive, and potentially hazardous, these methods give novices only limited opportunity to experience real working conditions. Computer modeling technologies—Augmented Reality, Augmented Virtuality, Virtual Reality, teleoperation, and simulator—are envisaged to meet this challenge. To facilitate comparisons between different training schemes, a taxonomy is presented to identify distinctions. Skill transfer from the training program to real task performance is noted to be a critical ergonomics issue, and thus a cognitive‐motor spectrum was developed for classifying categories of transferred skills prevalent in current equipment operator training schemas.

Select this Article		Rapid Post‐Disaster Evaluation of Building Damage Using Augmented Situational Visualization Vineet R. Kamat, M.ASCE and Sherif El‐Tawil, M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)122 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents research being conducted at the University of Michigan to design and implement a new reconnaissance technology to rapidly evaluate damage to buildings in the aftermath of natural and human‐perpetrated disasters (e.g. earthquakes, explosions). The technology being designed will allow on‐site damage inspectors to retrieve previously stored building information, superimpose that information onto a real building in augmented reality, and evaluate damage, structural integrity, and safety by measuring and interpreting key differences between a baseline image and the real facility view. In addition, by using feedback from the actual building view, it will be possible to update structural analysis models and conduct detailed what‐if simulations to explore how a building might collapse if critical structural members fail, or how the building's stability could best be enhanced by strengthening key structural members. All damage evaluation analyses will be conducted on‐site, in real‐time, and at a very low cost. This will enable a quantum leap over current damage evaluation practices that are significantly prolonged, expensive to conduct, and often inaccurate. The objectives of this paper are to introduce the overall framework being developed and to present details on the method of rapidly computing global building damage measures using augmented reality.

Select this Article		Specification for Mapping Mixed Reality Visualization Technology to AEC Tasks Xiangyu Wang and Phillip S. Dunston ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)123 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Mixed Reality (MR) denotes the blending of computer‐generated content with real world environments in a single display, and it offers new options for interactions both with computer‐based design information and with project collaborators over the entire life cycle of the engineered facility. A thorough observation of the mostly lab‐based MR prototype applications in multiple domains highlights the need for a structured methodology addressing suitability and usability issues for the effective adoption of MR technology to occur. A methodology has been formulated for developing user‐centered, performance enhancing MR‐based systems to support performance of architecture, engineering, and construction work tasks. A case study was also implemented where the methodology was applied to select appropriate MR technologies for collaborative design review in mechanical contracting.

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IT IN EDUCATION

Select this Article		Interactive Multimedia Scheduling Book: Learning Anytime Anywhere Ihab M. H. Saad ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)124 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Global market and technological changes pose challenges as well as opportunities facing several industries, particularly the construction industry. Regular reviews and updates of curricula related to construction education become a necessity in order to respond to these changes as well as to the availability of new knowledge. One of the problems with the treatment of each of the curriculum courses as a totally separate and independent entity is that changes made in one course might not be echoed and reflected through other complementary ones. This paper presents an approach of developing “knowledge islands” representing the core contents of the curriculum, together with connecting bridges or interfaces linking these different islands to form an integrated and holistic approach to delivering instructional material. Exposing the students at an early stage of their educational experience to this approach will make them feel the interdependence and interconnection between different classes. The paper presents one of the modules of this integrated system in the form of a CD containing static core information not likely to change on a regular basis, as well as a PDA‐downloadable web site containing more dynamic information, reflecting changes in the use of tools, materials, methods and techniques. The selected platforms allow for user access to the curriculum contents anytime, anywhere, and at the users' own pace.

Select this Article		An Interactive Visualization Environment for Construction Engineering Education John I. Messner, David R. Riley, and Michael J. Horman ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)125 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract The ability to visualize the built environment is a critical skill required by design and construction engineering students. Students in Civil and Architectural Engineering programs typically learn to analyze project designs and plan their construction by reviewing 2D CAD drawings and developing Critical Path Method (CPM) schedules. With recent advancements in computer display technology, it is now possible to place students within a large‐scale, immersive projection display that allows them to experience and experiment with 3D, full‐scale virtual prototypes of construction projects. This advanced visual communication can significantly improve the ability of students to comprehend, learn, and gain experience with reviewing designs for constructability and planning the construction of complex building and infrastructure projects. This paper presents the current status and vision for ongoing research into the implementation of advanced visualization technologies within the Construction Engineering and Management option in the Architectural Engineering Department at Penn State. The goal of our ongoing research is to improve engineering education in building and infrastructure design and construction through the use of interactive construction learning modules in an immersive virtual reality environment. The development of a Virtual Construction Simulator (VCS) is discussed which will allow students to immerse themselves into a 3D construction project, perform a detailed analysis of the design, and develop a plan for the construction process. The successful implementation of 4D Computer Aided Design (CAD) modeling (3D CAD with schedule time as the 4th dimension) in an undergraduate curriculum is presented with important lessons learned. The process for visualizing these 4D CAD models within a large immersive display system is also described. The results of this process yield useful experience in the development of a visualization facility and the implementation of 4D CAD in an immersive display system. These lessons along with the future learning module development are presented.

Select this Article		Comparison of Manual and User‐Guided Methodologies for the Classification and Retrieval Construction Site Images Ioannis K. Brilakis and Lucio Soibelman ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)126 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract The amount of original imaging information produced yearly during the last decade has experienced a tremendous growth in all industries due to the technological breakthroughs in digital imaging and electronic storage capabilities. This trend is affecting the construction industry as well, where digital cameras and image databases are gradually replacing traditional photography. Owners demand complete site photograph logs and engineers store thousands of images for each project to use in a number of construction management tasks like monitoring an activity's progress and keeping evidence of the “as built” in case any disputes arise. So far, retrieval methodologies are done manually with the user being responsible for imaging classification according to specific rules that serve a limited number of construction management tasks. New methods that, with the guidance of the user, can automatically classify and retrieve construction site images are being developed and promise to remove the heavy burden of manually indexing images. In this paper, both the existing methods and a novel image retrieval method developed by the authors for the classification and retrieval of construction site images are described and compared. Specifically a number of examples are deployed in order to present their advantages and limitations. The results from this comparison demonstrates that the content based image retrieval method developed by the authors can reduce the overall time spent for the classification and retrieval of construction images while providing the user with the flexibility to retrieve images according different classification schemes.

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ENTERPRISE‐LEVEL IT

Select this Article		Construction Firm Performance and IT Utilization Mohammad El‐Mashaleh, William J. O'Brien, and R. Edward Minchin ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)127 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract This paper examines the impact of information technology (IT) utilization on construction firm performance. Based on empirical data collected from 74 US construction firms, analyses provide evidence that IT has a positive impact on overall firm performance, schedule performance, and cost performance. Firm performance is a composite score of several metrics of performance: schedule performance, cost performance, customer satisfaction, safety performance, and profit. No relationship is found between IT utilization and customer satisfaction, safety, or profit, although this may be due to limitations of the study given strong correlations between IT utilization and cost and schedule performnance. The empirical evidence of positive association between performance and IT use complements survey respondents' subjective assessments of the association between IT use and firm performance. While not providing detailed return on investment type information, in general the research should encourage firms to adopt and invest in IT tools.

Select this Article		Use of IT in Managing Environmental Risks in Construction Projects Sanjaya De Zoysa, Yugui Wang, and Alan D. Russell ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)128 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Models are described of the physical, political, economic, social, and regulatory environmental dimensions of a project in support of an IT‐based strategy to assist with risk management. Two case studies in the form of a major highway project and a floating bridge project are used to illustrate the implementation of the representation scheme described and its integration with a project risk view. The models are formulated in a manner that allows the capture of an organization's knowledge on environmental characterizations and risk issues that is gained over time. Modes of re‐using the encoded knowledge in developing project‐specific risk registers are also discussed.

Select this Article		A Construction Business Automation System (CBAS) Dong‐Eun Lee, M.ASCE and Jonathan J. Shi, M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)129 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Delivering a constructed facility requires a contractor identifying, documenting, implementing, and executing thousands of business processes. Business Process Reengineering (BPR) and Automation (BPA) decompose business management into processes, and explore information sharing in a virtual enterprise setting. Workflow technology (WT) originated from Office Information Systems (OIS) supports definition, execution, coordination, and maintenance of business processes in a distributed environment. This research introduces a system prototype, named Construction Business Automation System (CBAS), for modeling and automating construction business processes by using workflow and object technologies. Automated construction management tasks, named Workflow Distributed Internet Applications (Workflow DNAs), support the reusability of the developed software components, simplify process modeling, and execute business processes. This paper presents the technologies developed in the prototype including: (1) the object‐oriented reusable component technology for modeling construction management tasks, (2) the Construction Business Process Modeler (CBPM), (3) the Request Driving (RD) methodology for raising business requests and instantiating corresponding process instances, and (4) the workflow technology for executing business process instances. An example process is used to illustrate these involved topics.

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MODELING AND OPTIMIZATION

Select this Article		Layout Planning of Construction Sites Considering Multiple Objectives: A Goal‐Programming Approach Hesham M. Osman and Maged E. Georgy ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)130 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract The construction site layout planning problem has been studied by several researchers for the last 15 years; each presenting it from his/her own perspective. Yet, one fundamental aspect of site layout planning was not as well investigated and documented in the literature, that is considering several planning objectives simultaneously. In principle, objectives need to be achieved by a site layout are many and could include transportation costs, labor movement, material handling, safety consideration, etc. These objectives are rather heterogeneous and in some cases conflicting. The paper attempts to handle this reality by using the optimization capabilities of goal programming (GP). While traditional optimization tools aim at finding the optimum solution for an objective function, GP seeks a solution that satisfies as many goals as possible rather than optimizing a single goal, which fully suits the case in hand. Formulation and specifics of the GP model are elaborated on in the paper, including use of the analytical hierarchy process (AHP) to identify the priorities among the various objectives. Following the computerization of the model, a case study of a university campus extension project in Toronto, Canada, was utilized to demonstrate the workings of this model.

Select this Article		Situation Based Modeling for Construction Productivity Eldon Choy and Janaka Y. Ruwanpura ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)131 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Both published and unpublished reports show that, in construction projects, site productivity losses range from 40% – 60%. Productivity is an important issue in construction because of the interaction among labor, capital, materials, and equipment. Construction site operations are also very complex, and they involve complicated relationships among numerous tasks. During construction, various factors, obstacles, uncertainties, and triggering situations affect a site's productivity within these relationships or tasks. Understanding the impact of various triggering situations on productivity could definitely improve the performance of and create value for the construction industry. The tool explained in this paper directly investigates and models these triggering situations to predict productivity using a modeling technique called situation‐based simulation modeling. This tool and methodology could also model the cause‐and‐effect relationships among various triggering situations that previous construction models have ignored. The simulation results not only are able to predict productivity very closely to the actual productivity observed at construction sites, but also provide recommendations to mitigate problematic situations to improve productivity.

Select this Article		Development of a Resource Scheduling Model Using Optimization Ralph D. Ellis and Jin‐Lee Kim ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)132 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract The CPM has proven to be helpful only when the project deadline is not fixed and the resources are not constrained by either availability or time. Resource‐constrained scheduling arises as a result of problems with the availability of resources. It is necessary to apply the availability of resources into a scheduling process for this reason. The objective of this paper is to present an optimal algorithm for a resource allocation model, which would be implemented into a framework for the development of an integration model. This framework for the development of an integration model for the resource‐constrained scheduling is discussed. An optimal resource allocation model is presented within the framework of an integration model. Unlike present heuristic‐based resource allocation models, the model does not depend on any set of heuristic rules, but adopts the concept of future float to set the order of priority when activities compete for resources. The model determines the shortest duration by allocating available resources to a set of activities simultaneously. Genetic algorithms (GAs) are adopted to search near‐optimal solutions. A case example is solved to illustrate the performance and effectiveness of the resource allocation model. The results indicate that the model is capable of producing near‐optimal scheduling alternatives, compared to a single solution that is produced by either the total float model or the least impact model.

Select this Article		Comparative Study of Discrete‐Event Simulation and System Dynamics for Construction Process Planning Sangwon Han, Moonseo Park, and Feniosky Peña‐Mora ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)133 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Discrete‐Event Simulation (DES) has been the mainstream in the area of construction simulation. Recently, research has shown the possibility of applying System Dynamics (SD) to the construction management discipline. Unlike DES, which is based on statistical analysis and queuing theory, SD is able to represent the complex system of construction management through capturing feedback effects, managerial actions, and soft variables such as schedule pressure and morale, which are important in determining project behavior. Though SD is capable of representing such variables and relationships, the validity of SD models has often been questioned because when modeling with SD, it is difficult to attain as much detail as when modeling with DES. Therefore, SD has not been fully adopted to simulations in the area of construction management, despite its advantages. To gain widespread use in the construction management area, SD needs to address operational details. In this paper, an SD based earthmoving process model is presented to explore ways in which operation details can be represented using SD. Initially, an SD based earthmoving model is proposed and for the purpose of comparison, and is tested against a DES counterpart model, created using STROBOSCOPE. The tests have shown that the simulation results generated by the SD model are as accurate and reliable as those of the STROBOSCOPE models. The specifics of this comparison are identified, including how the SD model is created from and compared to DES model at an operational level. These research findings support the widespread use of SD in the area of construction management; thus, aiding in the representation of the complexities inherent in construction.

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NEURAL NETWORKS AND FUZZY LOGIC

Select this Article		A Framework for Integrating Fuzzy Expert Systems and Discrete Event Simulation Ahmed A. Shaheen, Aminah R. Fayek, and S. M. AbouRizk ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)134 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract This paper provides a framework for integrating fuzzy expert systems with discrete event simulation, which will be utilized to enhance the input modeling process in discrete event simulation. Predicting the activity output (i.e. duration) using fuzzy expert systems will provide a new modeling feature to discrete event simulation. In previous studies, fuzzy set theory was mainly utilized to control resources in discrete event simulation. The proposed integration is designed to provide real‐time prediction of the activity output (i.e. duration) by capturing and modeling the changes in the factors affecting the activity output whenever the simulation time advances. The paper will show how this integration is achieved and how the inputs are handled in the integrated model.

Select this Article		Selecting Pile Construction Method Using Fuzzy Approach Tarek M. Zayed ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)135 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract The selection of pile foundation construction method depends mainly upon the subjective opinion of construction practitioners. Therefore, this experience has to be documented and stored in the intelligent company database for usage in future pile construction projects. This research introduces an attempt to store the experts' subjective experience using a fuzzy expert system (FES) or fuzzy model. The proposed model uses soil type, environmental conditions, water table position, and granular strata location as input variables. It produces the appropriate pile construction method and its associated membership value as outputs. The FES system is designated based upon construction facts and practitioners opinion. It is validated and a sensitivity analysis is performed to check its sensitivity to any changes in the inputs. It proves its robustness in selecting the appropriate pile construction method.

Select this Article		Fuzzy Logic Approach to Forecast Project Duration in Construction Projects Vellanki S. S. Kumar, Aff.ASCE and G. C. S. Reddy ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)136 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Network‐based techniques as planning tools are widely used in construction industry. They are usually carried out in an unstructured form with considerable reliance on the planner's judgment, imagination, and intuition. In addition, the competitive nature of construction industry has also contributed to the development of nontraditional decision‐making tools. Thus, a more accurate method is necessary to obtain project duration in construction projects. The availability of computer technology (both hardware and software) allows fuzzy logic for the prediction of accurate project duration. This paper describes a methodology to identify the project duration by incorporating qualitative as well as quantitative factors of the construction industry. The qualitative factors are converted into numerical measures by giving suitable membership values. This relies on advanced mathematical tools in addition to construction knowledge rules defined by planning experts to enhance and automate the planning process of complex projects, where conventional model‐based approach is very difficult to implement. Furthermore, this methodology makes the experts' knowledge explicit and can be applied mechanically to other projects, mutatis and mutandis. A case study is worked out to demonstrate the applicability of the proposed methodology and this can be easily computerized.

Select this Article		Neural‐Risk Assessment System for Construction Projects Pedro Maria Sanchez ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40754(183)137 Online Publication Date: 22 November 2005 Full Text: \| Download PDF
	+ -	Show Abstract Risk management is not a new topic in construction industry. Its main problem relies in assessing the risk impacts and as well in forecasting the possible costs of these risks. Transforming the risk impact into money terms certainly is not an easy thing to do. Traditionally within construction companies, risk management has been adopted; nevertheless, the work has been concentrated mainly in risk analysis. For doing this risk analysis, a large number of mainly probabilistic techniques (for example Monte Carlo Simulation, Latin‐Hypercube and Sensitivity Analysis) for determining the behaviour of the risks have been employed; nevertheless, the quantification of the risks is money terms is still lacking. Nowadays, having a risk management system integrated into the company's organisational structure is a necessity that needs to be satisfied; this system should deals with all the project risks. The main goal of this research‐work is to quantify in terms of money the cost of the risks involved in construction projects. For that reason, a list of Risk‐Factors (RF) has been created in order to model the behaviour of the risks for the chosen construction project. This is made with the help of the Neural‐Risk Assessment System (NRAS). The core parts of the system are represented by Artificial Neural Networks (ANN) and risk management. The objectives of the research are: to identify the most common risks in infrastructure projects in Germany, to quantify the risks in terms of money, to analyze and evaluate their impact to the Contractor's profit, to proof the reliability of using neural networks in the management of risks, to offer to the contractor an alternative tool to forecast the possible cost of risks.