You are not logged in You are not logged in to this journal. Log In

Journal of Materials in Civil Engineering / Volume 15 / Issue 2 / TECHNICAL PAPERS

LOG IN or SELECT A PURCHASE OPTION:

Durability of Boston Blue Clay in Waste Containment Applications

J. Mater. Civ. Eng. 15, 144 (2003); http://dx.doi.org/10.1061/(ASCE)0899-1561(2003)15:2(144) (9 pages)

John L. Daniels, P.E., M.ASCE1, Hilary I. Inyang, M.ASCE2, and Iskandar K. Iskandar3

1Assistant Professor, Dept. of Civil Engineering and Global Institute for Energy and Environmental Systems, Univ. of North Carolina, 9201 University City Blvd., Charlotte, NC 28223.
2Duke Energy Distinguished Professor, Dept. of Civil Engineering and Dept. of Geography and Earth Science, and Director, Global Institute for Energy and Environmental Systems, Univ. of North Carolina, 9201 University City, Blvd., Charlotte, NC 28223.
3Research Physical Scientist, U.S. Army Corps of Engineers Cold Regions Research and Engineering Laboratory, Hanover, NH.

(Submitted 2 October 1002; accepted 5 March 2002)

An experimental investigation of the durability of natural and polymer-amended Boston Blue Clay (BBC) used in waste containment applications was conducted. Durability was assessed in terms of hydraulic conductivity and crack formation in response to freeze-thaw- and desiccation-induced stresses. The polymers tested were nonionic polysaccharide (guar gum) and cationic polyacrylamide (PAM) with aqueous concentrations ranging from 0.25 to 8.00 g/L. BBC proved resistant to shrinkage cracks from desiccation, but susceptible to ice lensing from the application of freeze-thaw cycles. The saturated hydraulic conductivity of natural BBC increased from 5×10−5 to 1×10−3 cm/s after five freeze-thaw cycles. The saturated hydraulic conductivity for guar- and PAM-amended BBC also increased in response to freeze-thaw cycling; however, both the initial and final values were nearly an order of magnitude lower than those of natural BBC. In terms of crack formation as identified with computed topography scans, extensive ice lensing was observed in both the unamended and guar-amended specimens, while the PAM-amended specimen exhibited no such behavior in response to freeze-thaw cycling. Crack formation from either desiccation or freeze-thaw cycling was quantified in terms of a crack area density (CAD) that decreased for both guar- and PAM-amended specimens, as compared with the natural BBC. In particular, the observed CAD values for natural and PAM-amended BBC subjected to freeze-thaw cycling were 69 and 8%, respectively. The observed CAD values for all BBC specimens subjected to desiccation stress were less than 3%. Overall, these results indicate that natural BBC may be unsuitable for waste containment applications where control measures are not implemented for frost penetration. Moreover, polymer amendment serves to improve the material by reducing crack formation and hydraulic conductivity.

© 2003 American Society of Civil Engineers

KEYWORDS

RELATED DATABASES

To view database links for this article, you need to log in.

ARTICLE DATA

Digital Object Identifier
http://dx.doi.org/10.1061/(ASCE)0899-1561(2003)15:2(144)

PUBLICATION DATA

ISSN

0899-1561 (print)  
1943-5533 (online)

Publisher

American Society of Civil Engineers

For access to fully linked references, you need to log in.

For access to citing articles, you need to log in.


Close

Your Recent History Recent History Help

Recently Viewed

  1. Durability of Boston Blue Clay in Waste Containment Applications
close