Huaibei Mining Industry Co., Ltd. Yangliu Coal Mine

为研究近距离煤层群重复采动下采场围岩应力响应及变形破坏规律,以潘二矿多煤层开采为工程背景,采用现场调研和数值模拟方法,分析了多煤层重复采动下不同煤层工作面围岩应力响应特征及塑性区演化规律。研究表明:18126工作面回采时,煤层间距越大,煤层垂直应力受采动影响也就越小;受7-1煤层和18126工作面的开挖卸荷作用,在卸荷大小上5-2煤大于4-1煤,卸荷范围上4-1煤大于5-2煤;受18225工作面开采影响,5-1煤层底板再次发生卸荷破坏,底板塑性区发育到底部与5-1煤垂直间距为59m;4-1煤沿煤层倾向塑性区再次发生扩张,最大集中应力为16.34MPa,最小卸荷应力为9.56MPa,应力差为6.78MPa,沿倾向4-1煤的卸荷范围主要集中在183~266m和543~615m。18125工作面开采后,4-1煤最大集中应力为19.0MPa,最小卸荷应力为7.44MPa,应力差为11.56MPa,位于18126工作面的开挖卸荷区。

In order to study the stress response and deformation failure law of surrounding rock in stope under close distance coal seam group repeated mining, taking the multi coal seam mining of Pan'er Mine as the engineering background, on-site investigation and numerical simulation methods are used to analyze the stress response characteristics and plastic zone evolution law of surrounding rock in different coal seam working faces under repeated mining of multi coal seams. The research shows that during the stoping of the 18126 working face, the larger the spacing between coal seams, the smaller the influence of mining on the vertical stress of coal seams; Due to the excavation unloading impact of the 7 coal seam and the 18126 working face, the unloading size of the 5 coal is greater than that of the 4 coal, and the unloading range of the 4 coal is greater than that of the 5 coal; Affected by the mining of the 18225 working face, the floor of the 5 coal seam undergoes unloading failure again, and the plastic zone of the floor develops to a vertical distance of 59 m between the bottom and the 5 coal; The expansion of the plastic zone along the coal seam dip direction of the 4 coal occurs again, with a maximum concentrated stress of 16.34 MPa, a minimum unloading stress of 9.56 MPa, and a stress difference of 6.78 MPa. The unloading range of the 4 coal along the dip direction is mainly concentrated in 183-266 m and 543-615 m. After the mining of the 18125 working face, the maximum concentrated stress of the 4 coal is 19.0 MPa, the minimum unloading stress is 7.44 MPa, and the stress difference is 11.56 MPa, located in the excavation unloading area of the 18126 working face.