Slope Stability of Sg Langat Under the Influence of Extreme Rainfall

This study aims to determine the geotechnical characteristics and behavior of soils in Sg Langat with different angles of slopes, the effectiveness of groundwater situations, and the effect of heavy rainfall on slope failure through numerical modeling. Critical slope failures happen during or after rain. Landslides, a natural disaster associated with sliding, are one of the catastrophes that can lead to the loss of lives. Thus, a study and analysis about  the effect of extreme rainwater on slope strength is done to estimate the stability of slopes according to the extreme rainfall. This study is substantially to probe the effect of rainfall infiltration on slope stability with a shear strength of unsaturated soil and to determine the factor of safety of the unsaturated soil slope affected by rainfall intensity and different boundary conditions through numerical modeling. This analysis is performed by using GeoStudio software to imitate the soil characteristics and the behavior, with the given data of rainfall in a certain area. This review presents the numerical analysis of different slopes regarding former cases that are subordinated to extreme rainfall from different places. It is shown that Channel 2 has higher pore-water pressure than Channels 1 and 3, where phase 2 attained a higher pore-water pressure value of 78.08 kPa, whereas phase 1 reaches 67.95 kPa of pore-water pressure. In Channel 3, the factor of safety shown is the highest among all the channels which are 0.63, 0.88, and 1.11 for minimum, intermediate, and maximum values, respectively. The pros and cons of the numerical approaches are discussed and come with some general modeling recommendations.