开挖过程中边坡稳定性研究及两种安全系数之间的转化

为了研究边坡在开挖过程中的安全状况，以及有限元强度折减法和极限平衡法所求得的安全系数之间的关系，分别采用有限元软件ANSYS和极限平衡软件Slope／W对开挖过程各个阶段边坡的稳定性进行了计算分析．通过研究两种方法所采用的屈服准则的内在联系，找到了这两种方法所求得安全系数的转化方法，并对利用两种方法求出的边坡安全系数进行了对比分析．研究结果表明，在开挖过程中，边坡的安全系数会出现先增大后减小的现象；在平面应变条件下，采用平面应变莫尔一库仑匹配DP5准则求出的边坡安全系数，与传统极限平衡法求出的边坡安全系数最接近，误差小于8％．

Research of slope stability and conversion between two safety factor during excavation

In order to study the slope security situation during excavation and the relation- ship between the safety factor obtained from the finite element strength reduction and limit equilibrium method, using the finite element software ANSYS and limit equilibrium soft- ware SLOPE/W to calculate and analyze slope stability for excavation process various sta- ges. By studying the intrinsic link of yield criteria the two methods adopted, finding the conversion methods of safety factor. Then using two safety factor to comparative analysis the two methods. The results are that during excavation process, the safety factor will ap- pear first increases and then decrease phenomenon; in plane strain conditions, the slope safety factor calculated by using the plane strain Mohr-Coulomb criterion and conventional limit equilibrium method is the closest, the error is less than 8%.