考虑孔隙水压力的土坡稳定性的有限元下限分析

以极限分析下限法理论为基础，应用有限单元思想离散结构物，建立了同时满足平衡条件、应力边界条件、屈服条件和应力间断条件的静力许可应力场，其中孔隙水压力被当作一种类似于重力的外力荷载。引入线性数学规划手段后，得到了考虑孔隙水压力的边坡稳定的下限法数学规划模型，由此可以求出安全系数的下限解及其对应的应力场。最后，以2个经典的土坡为算例，与多种方法的分析结果比较，论证了该方法的正确性。

Lower bound analysis of soil slope stability using finite elements subjected to pore water pressure

Based on the theory of lower bound limit analysis, finite element are used to discretize the mechanism. The statically admissible stress fields that are satisfied the conditions of equilibrium, stress boundary, yielding and stress discontinuity, are constructed. The pore water pressure is considered as an external force, similar to gravity. By using the idea of linear programming, lower bound limit analysis models of mathematical programming for slope stability are established; the model can evaluate the safety factors and stress field of lower bound. Finally, taking two classical soil slopes for examples of calculating slope stability, the comparisons among the results of various methods are made. The results indicate the correctness of the method and the program.