采动诱发断层损伤滑移及其影响因素敏感性分析

Fault damage induced by mining and its sensitivity analysis of influencing factors

为研究采动诱发断层损伤滑移演化规律,结合现场微震监测,引入断层损伤变量作为评价断层滑移失稳的指标。并运用正交模拟试验,对断层损伤变量影响因素进行敏感性分析。研究表明:工作面开采影响下断层损伤滑移分为断层损伤起裂、断层扩展贯通、断层滑移错动3个阶段。随工作面靠近断层,断层损伤变量呈逐渐增大趋势。断层损伤变量受开采因素、断层因素、地应力水平3者综合影响。确定开采因素中工作面距断层距离、工作面斜长对断层损伤变量影响为高度显著,采厚影响不明显。断层因素中断层倾角、断层内摩擦角对断层损伤变量影响为高度显著,断层内聚力为一般显著,其它断层因素影响不明显。地应力水平中侧压系数对断层损伤变量的影响高于埋深。

In order to study the evolution law of fault damage and slip under the mining effect,combined with microseismic monitoring,a fault damage variable was introduced to evaluate the risk of fault slip. Sensitivity analysis was conducted to evaluate the factors that affect the fault damage variable by orthogonal simulation test. The results show that the fault damage and slip is divided into three stages: fault damage initiation,fault damage propagation and fault slip.With the working face close to the fault,the fault damage variable gradually increases.Fault damage variables are affected by mining factors,fault factors and in-situ stress level. Among the mining factors,the distance from the fault and the inclined length of working face are highly significant influence factors,while mining thickness has no obvious effect.Among the fault factors,fault dip angle and fault friction angle are highly significant influence factors,fault cohesion is generally significant,and other fault factors have no obvious effect. The influence of lateral pressure coefficient on the fault damage variable is higher than that of buried depth.