Slope stability assessment of remedial measures adjacent to transmission tower

Abstract

Slope stability analysis has received an increased attention in construction and development to ensure public safety and avoid economic loss. A high and steep soil slope failure had occurred on the slope adjacent to a newly built transmission tower in Murum, Sarawak. An effective slope remedial measure is demanded to protect the transmission tower. This paper presented the slope stability assessment conducted using a well-established Finite Element Method computer software, i.e. “PLAXIS 2D” and “PLAXIS 3D”. Two remedial works alternatives had been proposed, which including retaining wall and secant bored pile. The slope stability of each remedial works was assessed in term of factor of safety (FOS). The impact of the material model on FOS was assessed using both Mohr-Coulomb model (MC) and Hardening Soil model (HS). Topography, laboratory and field data were obtained to simulate the actual slope failure. The slope stability assessment conducted found that the most effective remedial work is secant bored pile (SBP) to prevent soil movement. FOS obtained from PLAXIS 3D was more conservative in complex geometry. Material model did not significanty impact FOS. FOS of HS model was slightly lower than MC model. The remedial measures were assessed with respect to the slope stability only which it did not consider the factor of construction cost.