Tunnel excavation changes the original stress state which directly leads to the surrounding rock fracture, many researches focus on the stress or displacement evaluation surrounding an opening or a tunnel. Flaws and openings dramatically change the state of internal stress within the rock mass, and the internal stress concentrates at some certain positions surrounding the opening. When the flaws and openings simultaneously exist, the internal stress interacts. To discuss about the stress evolution surrounding the flaw and opening, this study used the PFC program to establish numerical models containing one open flaw and two circular openings. Under uniaxial compression, the stress distributions surrounding the flaw and the openings at different loading stages and different flaw orientations were presented and the principal stress evolutions around the flaw and the openings were analyzed. The proposed numerical method in measuring local stress can be useful to evaluate the local stress distribution and evolution surrounding the flaw and opening.

隧道开挖改变了原始应力状态，直接导致了围岩的破裂，许多研究集中在洞口或隧道周围的应力或位移评估上。缺陷和开口会极大地改变岩体中内部应力的状态，并且内部应力集中在开口周围的某些特定位置。当缺陷和开口同时存在时，内部应力会相互作用。为了讨论围绕裂纹和开口的应力演化，本研究使用PFC程序建立了包含一个开口裂纹和两个圆形开口的数值模型。在单轴压缩下 给出了裂纹在不同加载阶段和裂纹方向上的应力分布情况，分析了裂纹在裂纹周围的应力分布。所提出的测量局部应力的数值方法可用于评估缺陷和开口周围的局部应力分布和演化。