Comparative analysis of several rock slope stability rating system: A case study at Kajang SILK highway

Abstract

Multiple rating systems have been used to quantify the stability of rock slope in Malaysia. Rock Mass Rating (RMR), Slope Mass Rating (SMR), Qslope rating system and limit equilibrium analysis to produce Factor of Safety (FOS) using Barton's equation were compared in this article. A rock slope which exhibits instabilities on Kajang SILK highway labeled as KSB was selected as the case study. Low scores recorded for each rating system (RMR=7, SMR=13.7, Qslope = 0.019) with FOS value of 0.73 in wet condition. Interpretation of each score shows similarity between different classification systems, agreeing that the slope was unstable and indicates failure. Observation on site further proving a failure has occurred, which was a wedge (120°/40°) due to intersection between joint set J3 (55°/68°) and a fault plane (150°/45°).