锚杆锚索支护的回采巷道采后不及时冒落,形成特殊的沿空漏风边界的采空区流场.运用有限元数值模拟方法,结合铰法小青矿S2—705工作面现场实际,从理论上描绘了采空区漏风流动规律的改变特征。给出风流强度分布图解.研究认为,不冒落形成的沿空漏风边界是工作面向采空区的漏入、漏回的主流边界。漏风强度最高;贴近工作面边界的冒落非压实带存在平行渗流.这种流势导致了在下游回风侧的沿空巷道内形成瓦斯集聚,并提出了预先拆锚杆卸顶或局部通风机抽排放两种解决途径.图5,参5.
As the roof can not cave in time in bolt and anchor cable supporting extraction roadway, a goaf flow field with special air leakage boundary along goaf is formed. The finite element numerical simulation method is used, combined with the locale practice of S2-705 working face of Xiaoqing mine, Tiefa Coal Industry Group, the varied characteristics of flow law of goaf air leakage were depicted in theory, and the distributing graph of airflow intensity was given out. It was pointed out that the air leakage boundary along goaf formed without caving is the main boundary that flow into and flow out of goaf from working face, and the air leakage intensity is at the tiptop; the parallel seepage exist in caving non-compacted zone closed to the boundary of working face. The flow trend leads to the gas conglomeration in roadways along goaf at the backward position of return air side, at the same time, two solving approaches, namely dismantling bolt in advance to discharge roof and drainage by auxiliary fan, are put forward. 5figs., 5refs.