不连续面对矿井稳定性的影响

Influence of Discontinuous Surface on Mine Stability

为研究地下矿山岩体的工程特性和水文地质因素对巷道稳定性的影响,采用离散元数值模拟方法,计算了不连续面特征、不连续面物理性质、初始应力和巷道尺寸等因素在不同水平下的巷道安全系数F_(SN),并与完整岩石安全系数F_(SI)进行比较分析。结果表明:在所有影响巷道安全系统的因素中,高于显著性水平的因素是巷道尺寸、侧压比和不连续面的特征,即裂隙长度、不连续面开口、不连续面发育度。不连续面施加的孔隙水压力会影响不连续面的有效应力与剪切强度,从而导致安全系数平均降低23%。现场工程实际验证了理论研究的正确性和理论在工程应用上的良好效果。

In order to study the influence of the engineering characteristics of rock mass in underground mine and hydrogeological factors on roadway stability,the discrete element numerical simulation method was used to calculate the safety factor F_(SN) of roadway under different levels of discontinuous surface characteristics,physical properties of discontinuous surface,initial stress and roadway size.And the obtained F_(SN) was compared with the complete rock safety factor F_(SI).The results show that among all the factors affecting the safety factor of roadway,the factors higher than the significance level are roadway size,lateral pressure ratio and discontinuity characteristics,namely fracture length,discontinuity opening and discontinuity development degree.The pore water pressure exerted on the discontinuous surface will affect the effective stress and shear strength of the discontinuous surface,resulting in an average decrease of 23%in the safety factor.The correctness of the theoretical research and the good effect of the theory in engineering application has been verified by the field engineering practice.