软岩巷道弹塑性变形的理论分析

Theoretic Analysis of Elastoplastic Deformation for the Tunnel in Soft Rocks

本文采用莫尔－库仑屈服准则和非关联塑性流动法则分析了轴对称软岩巷道的变形规律。从轴对称平面应变问题的基本方程出发，导出了软岩巷道弹塑性变形的位移理论解答，并给出了现有应力与位移理论解的适用条件。通过实例计算结果表明，本文得出的位移理论解与有限元数值解相当吻合。

In this paper,the deformation of the axisymmetrical tunnel in soft rocks is studied by using the Mohr-Coulomb yield criterion and non-associative plastic flow rule.A theoretic displacement solution of elastoplastic deformation for the tunnel in soft rocks is derived from the fundamental equations of the axisymmetrical plane strain, elastoplastic problem.The suitable condition of the existing theoretic solutions for stresses and displacements is also given.Through the computation results of a practical sample,it is shown that the displacement solution presented in this paper agrees with FEM solution very well.