THEORETICAL MODEL AND NUMERICAL ANALYSIS ON UNSATURATED EXPANSIVE SOIL SLOPE DURING DIGGING AND CLIMATE CHANGE COURSES (Ⅱ) NUMERICAL ANALYSIS

摘要

In order to investigate the sliding mechanism and process of expansive soil slope during digging and raining-evaporating courses,a FEM program named UESEPDC was designed based on the elasticity-plasticity-damage constitutive model and the elasticity-plasticity-damage consolidation model of unsaturated expansive soil proposed by the authors,and the numerical analysis on solid-liquid-gas tri-phases and multi-field couple problem was conducted for four stages: 1) Raining and evaporating before digging; 2) The moment at digging finishing; 3) Three days after digging finishing; 4) Multi-raining-evaporating cycles.The fields of stress,displacement,pore water pressure,pore air pressure,water content and suction in an expansive soil slope were obtained,and the pictures of crack damage evolution and plastic zone development in the same expansive soil slope for each analysis stage were shown.The research results clearly reveal the mechanism of expansive soil slope sliding progressively.This work has been funded by the National Natural Science Foundation of China (10372115).