공기흐름을 고려한 수리-역학적 연동모델에 의한 불포화 토사사면의 안정해석 = Stability Analysis of Unsaturated Soil Slope by Coupled Hydro-mechanical Model Considering Air Flow

다국어 초록 (Multilingual Abstract)

Stability analysis based on the limit equilibrium method combined with the result of infiltration analysis is commonlyused to evaluate the effect of rainfall infiltration on the slope stability. Soil is a three-phase mixture composed of solidparticle, water and air. Therefore, a fully coupled mixture theories of stress-deformation behavior and the flow of waterand air should be used to accurately analyze the process of rainfall infiltration through soil slope. The purpose of thisstudy is to study the effect of interaction of air and water flow on the mechanical stability of slope. In this study,stability analyses based on the coupled hydro-mechanical model of three-phases were conducted for slope of weatheredgranite soil widespread in Korea. During the process of hydro-mechanical analysis strength reduction technique wasapplied to evaluate the effect of rainfall infiltration on the slope stability. The results showed an increase of air pressureduring infiltration because rain water continuously displaced the air in the unsaturated zone. Such water-air interactionin the pore space of soil affects the stress-deformation behavior of slope. Therefore, the results from the three-phasemodel showed different behavior from the solid-water model that ignores the transport effect of air in the pores.

참고문헌 (Reference)

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