大采高仰斜综采工作面矿压显现规律研究

针对某矿701仰斜大采高工作面在高强度采动影响下引起的围岩控制难题,采用数值模拟、现场观测相结合的方法对其采场矿压显现规律进行了分析。结果表明,701工作面初次来压步距约为30 m,周期来压步距约为10 m;倾斜方向工作面两端先于工作面中部发生来压现象。通过工作面煤壁前方支承压力曲线分布可知,最大应力集中系数随工作面推进距离增加而增大。根据现场实测发现,工作面中部支架的工作阻力远高于工作面两端头,初次来压时,作用于工作面中部支架的最大载荷为40 MPa,周期来压期间为30 MPa左右。在两巷中实测顶底板及两帮移近量发现,采煤面推进至距离观测站10 m时,两帮最大移近量为416 mm,顶底板移近量为408 mm。

Mine Pressure Behavior of Fully Mechanized Mining Face with Large Mining Height for Steeply Dipping Coal Seam

In view of difficulty in the surrounding rock control caused by the high-intensity mining on the 701# steeply-dipping  working face with high mining thickness in one coal mine, numerical simulation combined with field observation were used to analyze the mine pressure behavior in the stope. It is found that the span distance for an initial weighting is 30 m and the span distance for periodic weighting is 10 m. As for the working face on the inclined side, the weighting was occurred firstly on both sides of working face and then in the middle of the working face. The plotted pressure curve of support in front of coal wall with working face showed that the maximum stress concentration factor increased with the increasing of the advanced distance of working face. According to the in-situ measurement, the working resistance of the support in the middle of working face is much higher than that on two ends of working face. During the occurrence of initial weighting, the maximum load forced on the support in the middle of working face was 40 MPa and around 30 MPa during the periodic weighting. It is found from the practical measurement of movement of roof, floor and two sidewalls when the coal mine face was advanced to the point 10 m away from the observation station, two sidewalls moved 416 mm closer to each other, and the roof and floor moved 408 mm closer to each other.