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针对高应力矿柱在遭受爆破、震动、远场地震等外界动力扰动时,往往发生整体失稳,甚至坍塌的现象,对深部矿山二步骤回采预留矿柱进行简化并建立了地质和力学模型,并对应力波在矿柱中传播进行了力学分析;进而采用FLAC3D数值模拟的方法研究了高径比为4的典型圆柱形矿柱分别在20 MPa、30 MPa、40 MPa静应力作用下竖向应力和塑性区的分布以及在此基础上分别受到峰值为10 MPa、20 MPa、30 MPa动力扰动时的力学响应特性。研究结果表明:矿柱在40 MPa高静应力作用下依然处于弹性变形阶段,可以保持自身的稳定;而高应力矿柱在遭到外界动力扰动时,会产生不同程度的塑性区,稳定性变差;静应力越大,动力的峰值越高,矿柱的稳定性越差,越容易失稳。得到了它们之间的定量关系并给出了保护矿柱稳定性的建议。
In the case of high-stress pillars subjected to external dynamic disturbances such as blasting, vibration and far-field earthquakes, the overall instability and even collapse phenomenon often occurs. The pillars reserved for the second-step mining in deep mines are simplified and geological and mechanical models are established , And the mechanical analysis of stress waves propagating in the pillars was carried out. Then the typical cylindrical pillar with height-diameter ratio of 4 was studied by FLAC3D numerical simulation method under the static stress of 20 MPa, 30 MPa and 40 MPa respectively The distribution of stress and plastic zone and the mechanical response of the zone under the dynamic disturbance of 10 MPa, 20 MPa and 30 MPa respectively. The results show that the pillars are still in the stage of elastic deformation under the high static stress of 40 MPa, and can maintain their own stability. However, the high-stress pillars will produce different degrees of plastic zone when subjected to external dynamic disturbances, Poor; the greater the static stress, the higher the peak power, the worse the stability of the pillars, the more likely to instability. The quantitative relationship between them and the suggestion of protecting the stability of ore pillar are given.