【摘要】 为了研究确定高应力软岩巷道二次支护时间和支护强度,以焦煤集团古汉山矿西大巷为研究对象,采用FLAC2D中的指数蠕变模型,研究分析围岩应力和围岩变形速度随时间的变化规律、二次支护时间及支护强度对围岩变形的影响规律.结果表明:采用指数蠕变模型得到的围岩变形随时间的变化规律与现场观测基本吻合,一次支护后围岩应力、围岩变形速度趋于稳定的时间段基本一致,在此时间段内进行二次支护后围岩蠕变速度最小,而且二次支护强度在0.25~0.30 MPa范围内可以有效地控制围岩蠕变速度,二次支护强度大于该范围,围岩的蠕变速度也不会再有明显的降低,保持了巷道稳定.更多还原

【Abstract】 In order to determine the secondary support time and intensity,the changing rules of the stress and deformation speed of surrounding rocks with time,the effects of the secondary supporting time and intensity of surrounding rocks on deformation were analyzed using exponential creep model of FLAC2D at west tunnel in the Guhanshan Mine of Jiaozuo Coal Industry Group.The results show that the deformation of surrounding rocks is in agreement with the actual observational result.After first support,the times required for steady state of stress and deformation speed of surrounding rocks are similar.Secondary supporting in this time,the creep speed of surrounding rocks is minimum.The creep speed of surrounding rocks is effectively controlled by secondary support within 0.25~0.3 MPa.Even the secondary support intensity beyond this range,the creep speed don’t reduce obviously any more.更多还原