Geo-Chicago 2016

Sustainable Slope Stabilization Using Biopolymer-Reinforced Soil


Different stabilization methods for improving soil behavior are commonly used to control slope stability problems in dams, levees and embankments. The present study demonstrates the use of biopolymer soil mixtures as a sustainable slope stabilization technique. Expansive clayey soils with low and high plasticity characteristics were collected from representative dam embankments located in the Dallas-Fort worth (DFW) area in Texas. The experimental study consists of mixing the collected soil with a commercially available biopolymer (guar-gum), at 0.25%, 0.5%, 1%, and 1.5% concentrations by weight. Strength and swell parameters of mixtures were obtained by direct shear test and swell pressure tests respectively. Results obtained indicate that the addition of biopolymer increases the shear strength and the swelling phenomenon of the soil. The 0.5% biopolymer soil mixture presents the optimum concentration based on its high strength and low swell potential. Strength parameters for both, non-reinforced soil and biopolymer reinforced soil (0.5% mixture) are used to conduct slope stability analysis using the limit equilibrium approach. The application of biopolymer reinforced soil substantially increased the factor of safety against shallow slope failures. This research highlights the adaptability of biopolymers in enhancing the strength parameters and providing a safe sustainable solution.