基于历史降雨序列的多层下蜀土边坡稳定性分析OA

Taking a Xiashu soil slide in Nanjing as the engineering case,the compression tests,permeability tests,quick shear tests,and repeated direct shear tests are carried out to analyze the effects of dry density on the physical properties and mechanical parameters of the soil,and then a three-dimensional numerical model is established to investigate the influences of daily rainfall and antecedent cumulative rainfall on the saturation,displacement and safety factor of a multilayer slope through numerical simulation.The results show that:(a)with the increase of dry density,the compression modulus,cohesion and internal friction angle of the soil all increase,whereas the permeability coefficient decreases;(b)daily rainfall has a significant influence on the saturation and displacement of shallow slope soils,while antecedent cumulative rainfall mainly controls the infiltration depth of rainfall,the greater the antecedent cumulative rainfall,the deeper the affected zone;(c)the influence of rainfall on the saturation of deep slope soils exhibits a certain lag effect,and the saturation changes significantly only when antecedent cumulative rainfall reaches a threshold value;and(d)the slope safety factor is negatively correlated with antecedent cumulative rainfall,whereas the rate of change of the safety factor is positively correlated with daily rainfall.