Title: Existing and Parametric Study on Rainfall-Induced Slope failure

Abstract:-- The rehabilitation of the Cameron Highlands hydroelectric scheme which includes a process of removing a volume of about 2.8 million cubic meters sediments. The reservoir sediment has been excavated, as it is transported from the dredging site to the placement site or disposal area in government-owned Sg. Jasin/Jasik site. The dredged reservoir sediments are generally defined as sandy silts with moderate organic materials. Existing and parametric slope stability studying landfill embankment/slope has been conducted to assess the slope stability in the dumping area. Rainfall-induced slope failure has been incorporated in this study to explain why even engineered slope encountered failure when the depth of infiltration reaches the critical depth. In this study, the thickness of this wetted zone is assumed to increase subsequently while the factor of safety is determined. Moreover, the effect of the thickness of the wetted zone against stability has been checked to determine the maximum wetted thickness to install any types of slope remediation works such as a horizontal drain. The parametric study demonstrated that the slope factor of safety is decreased with increasing the thickness of infiltration, i.e., the advancement of the wetting front. However, the analysis of the existing conditions of slopes indicates that the slopes are in stable condition. The slopes with slope angles of 35° and less are stable independently to the material friction, while the slope angle of 50° is not stable for material friction angle of less than 36°. It is noted that the material in this study would not have a friction angle greater than 34°. On the other hand, the slope angle of 40° has a critical friction angle of 28°, while the slope angle of 45° has a critical material friction angle of 30°.