ANALYSIS OF SLOPE FAILURE IN WEATHERED SCHIST RESIDUAL SOIL IN SEREMBAN, NEGERI SEMBILAN USING NON-LINEAR FAILURE ENVELOPE

Abstract

Slope stability issues seem to be the most significant problems in construction industry now days to many factors. Malaysia is located near to the equator and its climate is classified as hot and humid throughout the year. The situation becomes worse when geotechnical engineer never check stability against infiltration. Slopes are designed with the safety factor is still allowed but the slope collapsed. This problem occurs because slope which typically designed based on linear failure envelope. The infiltration of rainwater has adverse effect on slopes. This research considers two (2) methods to evaluate the stability of slope where are liner and nonlinear failure envelopes. The linear envelope will use the conventional equations that produced by Fellenius (1927) and Rahardjo & Fredlund (1991).  Non-linear envelope use  extend Mohr Coulomb shear strength model  introduced by Md. Noor and Anderson (2006). This study will analyse the slope failure and come out with some proposal on the methods that can be applied to prevent the slope failure in the future. The research used non-linear envelope extend Mohr Coulomb shear strength model. It was found that the value of effective cohesion and effective frictional angle are 38 kN/m² and 24⁰ for linear failure envelope. The value of effective cohesion and effective frictional angle are 0 kN/m² and 24⁰ for non-linear failure envelop. The result shows that the slope stability when infiltrated for 1.5 m is 1.59 for linear failure envelope and 0.98 for non-linear failure envelope. The data collections and analysis of the finding could be used as a reference for solution to the similar case in future.