位移不连续边界元法解多裂纹体的裂缝扩展

研究了用位移不连续间接边界无法解多裂纹体的裂纹扩展。由迭加原理，可分离出任一单个裂纹面在无限大板中的虚拟应力，从而求出有限或无限域中各条裂纹的应力强度因子值。文中提出一种与裂纹扩展相对应的方程组解法，当裂纹逐步扩展时，该解法不需重新形成和分解整个控制方程组，方程组的全部计算量大致等于一次方程组的求解及ｎ次回代（ｎ为裂纹扩展步数），因而大大减少了计算时间。多裂纹体的裂缝扩展研究为重力式碾压混凝土坝仿真破坏过程研究提供了条件。

Solution for crack propagation in multi-crack body by displacement-discontinuous boundary element method

In present paper study on the displacement--discontinuous indirect boundary element method for solving crack propagation in multi-crack body is introduced. By the principle of superposition fictitious stress on any individual crack surface in infinity can be resolved and also its value of stress intensity factor in infinity or finite body is obtained. In present paper an effective solution for equation group corresponding to crack propagation is also given. The present method of solution does not need to reform and resolve the controlled equation group during gradual propagation of crack. The total amount of calculation of equation group is about once solving equation group and n times backward substitution (where n is number of step of crack propagation) and therefore calculating time is greatly reduced. Study on the propagation of cracks in multi-cracked body leads to a good method for studying the actual simulated gradual destroy process of roller compacted concrete dam.