夹层坝基应力和稳定问题的平面非线性有限元分析

本文用平面非线性有限元法分析有软弱夹层的复杂岩基上混凝土坝坝体和坝基的应力和稳定问题,并编写有相应的计算程序。块体采用四结点等参数单元,软弱结构面则采用古德曼节理单元,并引入三结点的节理单元以模拟软弱结构面的尖灭端点。用初应力法作非线性迭代运算。剪切破坏判别采用莫尔—库仓准则。可以计算均质及复杂岩基上坝体、坝基的应力和位移以及破坏区的范围;还可模拟超载加荷,分析坝基的抗滑稳定性;同样可用于地下洞室围岩应力、位移和稳定的计算。

Two-Dimensional Finite Element Non-Linear Analysis for the Stress and Stability of Dam Foundations with Weak Intercalary Strata

In this paper, the stress and stability of a gravity dam on a complicated rock foundation with weak intercalary strata and of the dam foundation itself are analysed by means of a two-dimensional nonlinear finite element method, and a relevant computcr program is also presented. Isoparametric elements of four nodes are used for dam and rock masses, and Goodman's joint elements for weak intercalation. The joint elements of three nodes is introduced so as to simulate the tapered tip of weak intercalations. Stresses and displacements are calculated by means of initial-stress method—one of nonlinear iterative approaches. Mohr-Coulomb criterion is adopted for determining shear failure. This computer program can be used to calculate the stress and displacement of the dam on a homogeneous or complicated rock foundation and of the dam foundation itself, and determine the range of failure zones. It can simulate overloading to analyse slide stability of dam foundation, and can also be used to calculate the stress, displacement and stability of surrounding roel, of underground caverns.