ABSTRACT
The behavior of the slopes during the rainfall period was examined using a two-stage approach: analyze the infiltration and the ground water flow to obtain the distribution of pore water pressure in the slopes; and analyze the stability of the slopes with the pore water pressure profile obtained. The analysis confirmed that the landslides were indeed related to the long period rainfall. This chapter aims to present a case study on the effect of rainfall infiltration on the stability of two residual soil slopes that failed in 1999 after a heavy rainfall period in Malaysia. The magnitude of the maximum negative pore-water pressure is dependent on the shape of the hydraulic conductivity function and, to a lesser extent, on the rate of infiltration. The capability of the soil to store water under changes in pore-water pressures is represented by the soil-water characteristic function.
