Back Analysis and Potential Remedial Approach for Failure Slope at Bukit Nanas, Kuala Lumpur

Abstract

This study aims to validate the design parameters and stability of the slopes failure and propose acceptable remedial work by assessing the slope stability in Bukit Nanas, center of Kuala Lumpur. The slopes’ height is around 40 and 60 m with the gradient around 30°-45°. Totally 7 boreholes be carried out and the pertinent engineering properties were analyzed from laboratory testing and back analysis (in situ test). An established computer program SLOPE/W was used to carry out for slope stability analysis. The analysis method adopted was Morgenstern-Price’s Method. Based on the result of the field investigation and numerical analysis, the model of lowest factor of safety (FOS) that evaluated from the existing slope in critical section were selected and recommended for remedial work. Two option of remedial slope design had been proposed. The first option is soil nailing with grid beam and proposed drain while the second option is hybrid anchor with grid beam and proposed drain. Both options are used to improve the slope stability, but first option had been chosen as higher FOS and more efficient option. This remedial approach based on the main cause of slope failure in Malaysia can applied as reference in future slope remedial design.