Study Of Forming Mechanism And Stability In Raining Conditions For The Earthquake-shatter Slope

The earthquake and rainfall are important factors of slope instability. Earthquake not only caused a lot of direct disaster such as landslides, but also made a lot of cracked slopes which chould come into being potential disaster. Rainfall chould rise the phreatic surface of the groundwater in the slope which soften the surface soil and led to the occurrence of landslides. The earthquake stricken area may be in the rainfall area, so the stability study of these cracked slopes is an important topic of disaster prevention and mitigation. This paper ummarized the development law and failure mechanism of cracked slope which based on a large number data of cracked slope, and then simulated the rainfall infiltration process and got the development rule of the stability by element software Abaqus on the basis of the saturated-unsaturated soil seepage and shear strength theory.The main research contents of this paper are as follows:1. Concluded and summarized the characteristics and rules of the occurrence, development and distribution of the cracked slope based on the detailed survey data of Gulang, Wenchuan and Yushu and other well-known large earthquake.2.Made a preliminary analysis of the failure mechanism and failure mode of cracked slope based on the effect theory of slope characteristic and seismic wave in the slope.3.The rainfall process of cracked slope was simulated by Abaqus finite element software based on the seepage theory of saturated-unsaturated soil. It Analysed the changes of pore water pressure, saturation, displacement and the equivalent plastic strain of the slope during rainfall, in particular the change of the characteristic points near the seismic fracture which to evaluate the effect of earthquake cracks produced in the process of rainfall on slope seepage.4. Based on the above statistical analysis of the development characteristics of shatter slopes to design different numerical simulation and analysed the stability of slope in different conditions by the strength reduction method based on the strength theory of unsaturated soil. Reached the varying regularity of stability of cracked slope in the cases of different crack positions, crack depth, rainfall intensity, rainfall duration and coefficient of permeability.