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http://dx.doi.org/10.7843/kgs.2012.28.11.69

Hydro-mechanical Behavior of Partially Saturated Soil Slopes under Rainfall  

Kim, Jae-Hong (Dept. of Civil Engineering, Chonbuk National Univ.)
Im, Jae-Seong (Dept. of Civil & Environmental Engineering, Dankook Univ.)
Park, Seong-Wan (Dept. of Civil & Environmental Engineering, Dankook Univ.)
Publication Information
Journal of the Korean Geotechnical Society / v.28, no.11, 2012 , pp. 69-78 More about this Journal
Abstract
Conventional numerical analysis for rainfall-induced slope stability has been estimated by separating seepage and stress-strain behavior, respectively. Many researchers' models from commercial softwares and literatures define that partially saturated permeability is the only function of degree of saturation (or matrix suction) and then they do not consider hydraulic-mechanical characteristics for the analysis. However, in practice, the water flow processes in a deformable soil are influenced by soil skeleton movement and the pore water pressure changed due to seepage will lead to changes in stress and to deformation of a soil. The relationship between seepage and soil behavior causes a change of partially saturated permeability as well as saturated permeability with the lapse of time. Instability of partially saturated soil slopes due to infiltration would be analyzed from reduction of negative pore water pressure calculating the process of water flow based on predicted partially saturated permeability. Therefore, partially saturated permeability should be defined by the function of degree of saturation (or matric suction) and porosity. The paper presents the comparison between staggered and monolithic coupled analysis regarding seepage and stress deformation problems. As a result, the decrease in matric suction on soil slope from monolithic analysis is slower than that from staggered analysis.
Keywords
Monolithic analysis; Staggered analysis; Finite element analysis; Rainfall-induced slope stability; Partially saturated soil slopes;
Citations & Related Records
Times Cited By KSCI : 3  (Citation Analysis)
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