Crack propagation is a very important research subject within the field of rock mechanics. In this study, a J-integral based Maximum Circumferential Tensile Stress theory was applied to the conventional Discontinuous Deformation Analysis (DDA) Method for simulating crack propagation. First, according to the relevant theories of fracture mechanics, a crack propagation theory suitable for DDA was derived by calculating J-integral in DDA simulation. Then, the crack propagation algorithm was embedded in the DDA algorithm with an accurate judgement of the propagation direction. After that, the numerical calculation results were compared with the experimental results to verify the correctness of the crack propagation algorithm. The validated method was finally applied to simulate a landslide case with a preexisting crack. The results showed that the proposed method was applicable to simulating crack propagations in practical cases.

裂纹扩展是岩石力学领域中非常重要的研究课题。在这项研究中，基于J积分的最大周向拉伸应力理论被应用到常规的不连续变形分析（DDA）方法中，以模拟裂纹扩展。首先，根据断裂力学的相关理论，通过计算J得出适用于DDA的裂纹扩展理论-在DDA模拟中不可或缺。然后，将裂纹扩展算法嵌入到DDA算法中，并准确判断其传播方向。之后，将数值计算结果与实验结果进行了比较，验证了裂纹扩展算法的正确性。最终将经过验证的方法用于模拟具有裂纹的滑坡情况。结果表明，该方法适用于实际情况下的裂纹扩展模拟。