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为了得到沿空留巷稳定阶段的底鼓机理与控制对策,通过岩石峰后蠕变试验,分析了损伤程度和围压增量对岩石峰后蠕变性态的影响。结果表明:岩石峰后蠕变破坏形式是类“X”状剪切破坏,破坏后块体会沿破裂面发生较大滑移;峰后岩石损伤程度越小,其蠕变速率越小,可以保持自稳的时间越长;提高围压可以减小峰后岩石实际承受的等效应力,进而改善其蠕变性态,相反,围压降低则会恶化其蠕变性态。最终得到:沿空留巷留巷稳定阶段底鼓的主要形式是底板破裂区峰后岩体的蠕变变形与其蠕变失稳后破坏块体沿破裂面的滑移。
In order to obtain the bottom drum mechanism and control strategy during the stabilization process of gob-side entry retaining, the influence of the degree of damage and confining pressure increment on post-peak creep behavior was analyzed by post-peak creep test. The results show that the post-peak creep failure mode is shear failure of the “X” shape, and the block will slip along the fracture surface after the failure. The smaller the rock damage degree after the peak, the smaller the creep rate, The longer the self-stabilization can be maintained. Increasing the confining pressure can reduce the actual equivalent stress of the post-peak rock and improve its creep behavior. On the contrary, the decrease of confining pressure will deteriorate its creep behavior. The main result is that the main form of the bottom drum at the stable stage of gob-side entry retaining is the creep deformation of the rock mass after the peak of the floor cracked area and the slip of the damaged block along the rupture surface after the creep failure.