基于流形方法的结构体破坏分析

STRUCTURE FAILURE ANALYSIS BASED ON MANIFOLD METHOD

在原有流形方法的基础上增加了模拟多裂隙结构体的破坏及跟踪裂缝扩展的功能。对于含有大量节理裂隙的结构 ,采用传统的摩尔 库仑准则 ,允许裂缝不仅沿原有的不连续面扩展 ,而且可以穿过完整介质 ,导致结构体的破坏。对于单条裂缝的扩展 ,用作者开发的二阶流形法与局部子域边界元法 (BEM)相结合 ,可精确地求出缝端应力强度因子 ,并模拟裂缝的扩展。在这一方法中 ,所模拟裂缝不受网格限制 ,可沿任意方向扩展 。

A numerical method is developed for simulating failure and propagation of muitiple cracks based on manifold method. For structures with large number of joints, the Mohr Coulomb law is used as the criterion of failure. The developed method permits crack not only to propagate along original discontinuities but also penetrate through the mass medium. For propagation of individual crack, the stress intensity factor can be accurately computed by the combination of the author developed second order manifold method with local sub region BEM. The criterion of crack propagation is made according to the theory of fracture mechanics. A simulation method for crack propagation freely through meshes is developed. It is shown from computational examples that the reasonable results can be obtained by the developed method.