Parametric Analysis of Factors Affecting the Rainfall Induced Slope Stability

Özçelik F. V., Selçuk M. E.

Turkish Journal of Geosciences, vol.3, no.2, pp.49-57, 2022 (Peer-Reviewed Journal)


Slope failures are one of the most important problems in geotechnical engineering. When slope failure occurs, devastating results occur both in human life and financially. Slope failures are frequently seen especially in regions where rainfall is high. The most important factor affecting slope stabilities is rainfall infiltration. It is known that infilled soils are generally unsaturated soil. Therefore, the analysis of infill slopes should be done within the scope of unsaturated soil mechanics. Rainfall infiltration causes the groundwater level to rise, which reduces the shear strength of the soil. Eventually, it can cause the slope instability. In this study, the effect of rainfall intensity, rainfall duration, soil permeability, groundwater level, cohesion of soil, internal friction angle of the soil, and slope angle of the slope on the slope stability were analysed parametrically by using Seep/w and Slope/w modules of Geostudio software. At the end of the study, different factor of safety numbers were found for each analysis, how much the parameters affected the slope stability were shown and interpreted. It has been observed by the analyses that the rainfall intensity affects the stability of the slope. It was found that there is a non-linear relationship between rainfall intensity and safety number. As the rainfall intensity increases, the negative pore water pressure in the soil decreases nonlinearly, and the factor of safety number of the slope similarly decreases.