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首先采用DDARF(discontinuous deformation analysis for rock failure)分析方法对双裂隙岩块进行单轴和双轴压缩模拟试验,研究了裂隙角度和侧向应力大小对岩块特性的影响,得到了裂隙岩块在这两种加载试验中的破坏过程、应力-应变曲线以及岩块中裂隙的起裂应力和岩块的峰值强度。在双轴压缩模拟试验中绘制了裂隙角度为45°的岩块在不同侧向压力下的强度包络线。其次,采用DDARF分析方法模拟劈裂试验中含裂隙试块的锚固效果,得到了4种不同锚固角度试块的轴向荷载–位移变化曲线和裂隙扩展规律。模拟结果与前人的类似条件下的试验结果相符良好。随后又将双裂隙试块双轴压缩模拟试验中得到的参数运用到一个地下洞室的工程实例中,用等效力学特性的方法分析对比了完整岩体和节理岩体洞室开挖完成后的破损状态的差异。最后运用DDARF分析方法研究了随机生成4组节理岩体的地下洞室的稳定性,得到了洞室节理围岩的裂隙扩展过程。同时通过对关键点位移的监测分析了锚杆的锚固效应。
Firstly, the uniaxial and biaxial compression simulation tests of double fractured rock mass were carried out by DDARF (discontinuous deformation analysis for rock failure) analysis. The influence of rock fracture angle and lateral stress on rock mass properties was studied. The failure process, the stress-strain curve and the initiation stress of cracks in the rock mass and the peak strength of the rock mass in both loading tests. In the biaxial compression simulation test, the strength envelope of rock mass with a 45 ° fracture angle under different lateral pressures is plotted. Secondly, using DDARF analysis method to simulate the anchoring effect of cracked block in the splitting test, the axial load-displacement curve and crack propagation law of the four different anchorage angle blocks were obtained. The simulation results are in good agreement with the experimental results under similar conditions. Subsequently, the parameters obtained from the biaxial compression simulation test of the double-fracture test block were applied to an underground engineering example. After the completion of the excavation of the intact rock mass and the jointed rock mass were analyzed and compared with the equivalent mechanical properties The difference in damage status. Finally, the stability of the underground cavern with four groups of jointed rock mass randomly generated by DDARF analysis is studied, and the crack propagation process of surrounding rock of the cavern is obtained. At the same time, the anchoring effect of anchor was analyzed by monitoring the displacement of key points.