基于强度折减法随机裂隙岩体结构稳定性分析

Stability analysis of random fractured rock mass structure based on the strength reduction method

克服裂隙岩体确定性分析方法的局限性,采用有限元强度折减法对节理裂隙随机分布的重力坝安全稳定性进行评价。运用Monte-Carlo方法,生成二维和三维随机节理裂隙网络模型,模型较为真实的还原了节理裂隙的分布情况;针对重力坝只含软弱夹层和同时含软弱夹层和节理裂隙两种情况,采用强度折减法对比分析其塑性区和水平位移变化情况。研究结果表明,含节理裂隙的重力坝坝基内部塑性区较多,且局部破坏严重,坝体的水平位移相对较大。该结果可为裂隙岩体地下工程的安全和稳定性研究提供参考。

In order to overcome the limitations of the fractured rock mass deterministic analysis methods, the evaluation of joints and fissures safety stability of the gravity dam was put forth by using the finite element strength reduction meth- od. The 2 D and 3 D random joint fracture network model were generated by Monte-Carlo method, which could reduce the real distribution of joints and fissures. For the two cases of gravity dams that only with soft rock strata and with soft rock strata and rock joints, the strength reduction method was used to comparatively analyze the plastic zone and the horizontal displacement. The analysis results showed that the plastic zone of the gravity dam with joints within the foun- dation was more, the local damage became serious and the horizontal displacement of dam became relatively large. Re- search results could provide a reference for the study on safety and stability of underground engineering of fractured rock mass.