Slope Stability Considering the Effects of Air Pressure and Seepage Under Heavy Rainfall Conditions

doi:10.16183/j.cnki.jsjtu.2021.302

Abstract

Abstract:

Rainfall infiltration analysis is one of the important methods for predicting engineering disasters. In order to effectively analyze the infiltration process of slope under heavy rainfall, based on the classical Green-Ampt model, a slope rainfall infiltration model considering the effect of saturated zone seepage and air pressure under the condition of non-uniform distribution of initial water content was established, and the corresponding expression of landslide stability coefficient was derived. The results show that the influence of slope size on rainfall infiltration is obvious. On the one hand, the expansion rate of wetting front increases with the increase of slope length, on the other hand, when considering the effect of air pressure, the smaller the slope length, the longer it takes to reach the same wet front. When the slope length increases to a certain extent, the difference is not obvious. In addition, the influence of seepage force on slope stability is greater than that of air pressure. Because the former gradually increases during the rainfall process while the latter is basically unchanged, the influence of seepage force increases, and the influence of air pressure decreases.

Key words: rainfall infiltration, initial water content, seepage in saturated zone, closed air pressure, slope stability

CLC Number:

TU42

YAO Maohong, CHEN Tielin, FAN Rong, YANG Zili, SHI Ye. Slope Stability Considering the Effects of Air Pressure and Seepage Under Heavy Rainfall Conditions[J]. Journal of Shanghai Jiao Tong University, 2022, 56(6): 739-745.

Figures/Tables 8

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