岩石边坡稳定的块体单元极限分析上限法

Upper bound limit method for stability analysis of rock slopes by block element method

将块体单元法与极限分析上限法相结合,提出了岩石边坡稳定的块体单元极限分析上限法。借助于块体单元法离散计算区域,通过块体系统速度场在结构面上满足Mohr-Coulomb屈服条件、关联流动法则、速度边界条件以及块体系统虚功原理,构成求解边坡强度储备安全系数上限解的非线性规划模型,模型的求解采用复合形法。最后研究了一个岩质楔形体边坡算例和小湾水电站进水口边坡实例,通过将块体单元法上限分析计算结果与刚体极限平衡法相比较,验证了该方法的正确性。

A novel upper limit method for rock slope stability analysis is developed.Block element method(BEM)is employed to disperse the computational area and to construct a kinematically admissible velocity field.A nonlinear programming model for the upper limit of safety factor of rock slopes is formulated,in which the velocity field satisfies the constrain conditions including the Mohr-Coulomb yield criterion on the slide surface,the associated flow rule,boundary conditions,as well as the visual work of the block system.The model is solved by the complex shape method.A wedge-block in a rock slope is studied,which verified the efficiency of the method.Finally,its application to the intake slope of Xiaowan Hydropower Station shows the practicability of the method to the slope.