局部安全系数法在土坡稳定分析中的应用

Application of Local Factor of Safety Method in Slope Stability Analysis

假定各条块的局部安全系数与滑动面的整体安全系数不相等,联合潘家铮极大值原理与优化算法构建了一种求解整体安全系数的新方法。对于给定滑动面,该方法将推力线与条块间力的倾角视为优化变量,利用优化算法寻找一组优化变量使此滑动面的整体安全系数达到极大值,同时可得到各条块的局部安全系数。在众多可行的滑动面中,选择整体安全系数最小的滑动面作为临界滑动面。利用该法对澳大利亚计算机应用协会(ACADS)的考题以及已有文献中的典型例题进行了计算,通过比较分析了该法的合理性。

It was assumed that the values of local factors of safety for each slice were different to those of total factor of safety of slip surface. A new method for determining the total factor of safety for given slip surface was presented by using Pan Jia-zheng maximum principle and optimization algorithm. The thrusting force line and inclination angles of slice forces were taken as optimization variables for given slip surface. The acceptable force vectors which gave the maximum value of factors of safety were determined and the corresponding factors of safety for given slip surface were also determined. In most feasible slip surfaces, the minimum slip surfaces of total factor of safety were taken as critical slip surface. Finally, the new method was adopted to study the examples used by Australia Computer Aided Design Society （ACADS） and in the existing literatures, the comparative studies have shown that the new method is rational and feasible and can be used in stability analysis.