Sustainable infrastructure development & risk reduction: Case study of stability analysis of geogrid supported slope

This article presents details of how the issue of slope stability was resolved using the first principles of soil mechanics. The plot required for installation of electrical substation has a boundary with private land. Just at the verge of the boundary there exists an 8m high cliff, substation being at lower level & private land at higher level. No activity from higher elevation can take place as the jurisdiction is separate & the boundary wall exists at higher elevation at cliff edge. The layout of electrical substation is such that it does not leave sufficient space to have a sufficient factor of safety for slope stability in line with slip circle method and soil parameters. To ensure the safety of work force, materials & machinery safe slope of soil was adopted to retain the cliff. Stability of slope was evaluated using method of slices without reinforcement which is generally accurate for practical pur-poses. As factor of safety was not adequate, the stability check with reinforcement was carried out. The design tensile force required for reinforcement was obtained. From design tensile force the ulti-mate tensile strength requirement of geosynthetic reinforcing material was carried out. The lateral stability was checked using basal reinforcement resisting outward horizontal thrust of slope. The ge-ogrid parameters were taken from British Board of Agreement HAPAS certificate.