下蜀土边坡降雨型滑坡的成因分析

Analysis on causation of rainfall-induced landslide of Xiashu loess slope

在分析降雨型滑坡破坏模式以及下蜀土边坡稳定性影响因素的基础上,对南京典型剖面下蜀土物理力学性质进行分析,总结了下蜀土滑坡的主要成因。研究结果表明,随着降雨过程中包气带水分运移,下蜀土非饱和土体边坡内孔隙水压力和岩土界面基质吸力的分布不断发生变化,土体抗剪强度也随之不断变化,受其影响,边坡极易发生降雨型滑坡。

Based on the analysis made on the failure mode of rainfall-induced landslide and the factor of impact on the stability of Xiashu loess slope, the physio-dynamical properties of Xiashu loess under the typical profile of Nanjing are analyzed herein, and then the main causation of Xiashu loess slope landslide is summarized as well. The study result shows that the distributions of both the pore water pressure in the unsaturated soil mass of Xiashu loess slope and the matric suction of rock-soil interface contin- uously change along with the moisture migration of aeration zone during rainfall process, and then the shear strength of the soil mass continuously changes as well, thus the rainfall-induced landslide is particularly prone to be happened on the slope under the impact of this.