弹塑性有限厚条法及工程应用

ELASTO PLASTIC FINITE THICK STRIP ELEMENT METHOD AND ITS ENGINEERING APPLICATION

本文采用大单元内划分小网格的方法判断塑性区范围。在弹性区及塑性区内选用统一的解析函数级数。以修正常刚度增量法为迭代方法，给出了塑性系数矩阵及塑性刚度矩阵的推导过程。假设小网格内的应力为常量，使求解过程方便化．编制了弹塑性有限厚条法在地下工程三维弹塑性围岩稳定性分析中的应用程序。

In this paper, a method dividing a big element into smaller meshes is adopted to judge the ranges of plastic zones. The analytical function series is unified in both elastic and plastic zones. The method of modified stiffness increment is used in iteration,and the plastic coefficient matrix and plastic stiffness matrix are given in derivation. The element stresses in the mesh are regarded as constants that makes the solution process simpler.The program is developed to analyze the stability of three-dimentional underground opening, and the stability of circular and elliptic openings are also analyzed.