超长工作面异常矿压显现与瓦斯涌出关系研究

Study on the Relation between Abnormal Mine Pressure Behavior and Gas Emission in Super-long Working Face

基于寺家庄矿15106大采高超长孤岛工作面复杂构造条件下开采实践,从煤壁片帮、顶板垮落、瓦斯不均衡涌出等角度对超长工作面异常矿压显现与瓦斯涌出关系进行了研究探讨。研究认为:深井超长孤岛工作面矿压显现呈现典型的"双峰"分布,工作面中部老顶并非一次性折断,而是在倾向方向分区域折断,并呈铰接状态;工作面来压呈现整体性大周期来压与区域性小周期来压并存特点,从来压强度与范围来看,大周期来压是上覆上位坚硬厚岩层大范围失稳所致,小周期来压是工作面下位基本顶周期性破断造成;工作面推进过程中瓦斯不均衡涌出也呈现周期性状态,每次大周期来压时均伴随有瓦斯超限,且周期来压持续时间与瓦斯超限时间呈现一致性增减关系。研究认为寺家庄矿超长工作面回采工艺与煤壁片帮、瓦斯不均衡涌出、顶板大面积失稳之间存在联动关系,对现场安全回采具有指导意义。

Based on the mining practice of 15106 high cutting and super long isolated island face in Sijiazhuang Coal Mine under complex structural conditions,we study and discuss the relationship between abnormal ground pressure and gas emission in super long working face from the aspects of coal wall,roof caving and unbalanced gas emission.It is considered that the ground pressure appearance in deep and super long isolated island working face presents typical'double peak'distribution,but the old roof in the middle of working face is not the same.The working face weighting is characterized by the coexistence of integral large periodic weighting and regional small periodic weighting.From the point of view of compressive strength and scope,the large periodic weighting is caused by the large-scale instability of the upper hard and thick strata,and the small periodic weighting is caused by the periodic breaking of the basic roof of the working face.During the process,the unbalanced gas emission also shows a periodic state.Each large period weighting is accompanied by gas exceeding the limit,and the duration of periodic weighting is consistent with the increase or decrease of gas exceeding the limit time.We analyze the linkage relationship between the mining technology of super-long working face in Sijiazhuang Coal Mine and the wall,unbalanced gas emission and large area roof instability,so as to return to the site safely.The mining has guiding significance.