Rainfall-induced shallow landslides involve complex hydrological and mechanical interaction. The measurement of hydromechanical behavior and quantification of mechanical parameters is critical for the early warning and management of hillslope landslides. The Babaoliao area in Chiayi, Taiwan, has a history of slope deformation;thus, a slope in that area with displacements was selected as a case study. This study used the fuzzy point estimate method and coupled hydromechanical model and also computed the local factor of safety. The probability of failure was assessed through reliability analysis and the model validated using historical rainfall event data. This study further
predicted the probability of failure with the same rainfall volume under different patterns. The results demonstrated
that the model can predict the tempo-spatial instability distribution of a hillslope. Different rainfall patterns affect the infiltration flux, leading to distinct slope failure times. This paper offers valuable insight into the warning threshold value for slope management.
Key Words: Shallow landslide, Fuzzy point estimate method, Local factor of safety, Probability of failure.