Instability of partially saturated soil slopes due to alteration of rainfall pattern

• Published in: Engineering geology Vol. 147-148; pp. 28 - 36
• Main Authors: Kim, Jaehong, Jeong, Sangseom, Regueiro, Richard A.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 12.10.2012
• Subjects: Climate change; Heavy rainfall; Infiltration; Instability; Landslides; Matric suction; Partially saturated soil; Partially saturated soils; Rainfall; Slope stability; Slopes; Soil (material); Stability; Climate change; Slope stability; Matric suction; Heavy rainfall; Partially saturated soil
• ISSN: 0013-7952; 1872-6917
• DOI: 10.1016/j.enggeo.2012.07.005

The influence of climate change on rainfall patterns has the potential to alter stability of partially saturated soil slopes. Changes in rainfall patterns have a strong influence on stability of partially saturated soil slopes, which recently have resulted in shallow landslides. In this paper, slope stability is assessed using a monolithically-coupled finite element model for a deformable partially saturated soil subjected to surface infiltration of water. Numerical analysis solves for the matric suction distribution over a two-dimensional cross-section of a soil slope while varying permeability, and considering a surface layer of soil with different permeability. The formulation of hydraulic conductivity for a coupled analysis includes dependence on porosity and degree of saturation to illustrate the effects of water infiltration and deformation behavior in partially saturated soils. Numerical examples demonstrate that change in rainfall patterns may trigger slope instability earlier in the rainfall event than for rainfall events of the past. Assessment of these simulations can provide an indication of the potential influence of climate change on shallow landslides in many mountainous areas in South Korea. ► The newest technology of numerical analysis is presented for distribution of suction. ► The code is monolithically coupled finite element code for slope problems. ► Climate change affects slope instability due to rainfall intensity. ► The mechanism of code is to analyze seepage and deformation simultaneously.