急倾斜煤层水平分段开采煤层厚度变化区矿压显现规律与防治技术研究

Research on the regularity and control technology of mine pressure in the region of coal seam thickness variation in steeply inclined coal seam by horizonal sectional mining method

针对急倾斜煤层水平分段开采煤层厚度变化区冲击压灾害频发现象,以王家山矿2号井水平分段开采工作面为工程背景,采用有限差分数值模拟(FLAC3D)方法,研究了急倾斜特厚煤层水平分段开采应力场和塑性区演化规律,揭示了急倾斜煤层水平分段开采煤层厚度变化区冲击矿压发生机理,并提出了防治对策。研究结果表明:在煤层厚度发生改变时,两巷道附近走向高应力逐渐在煤层厚度变化区内集中,直至转移至回风巷道顶板附近,最大值可达到40MPa,易导致回风巷道顶板出现冲击矿压情况。研究结果与现场实测相吻合。

In view of the frequent occurrence of rock burst disasters in the area of coal seam thickness variation in steeply inclined coal seam by horizonal sectional mining method,taking the horizontal sectional mining face of shaft No.2 in Wangjiashan Coal Mine as the engineering background,the evolution law of stress field and plastic zone of steeply inclined ultrathick coal seam horizontal sectional mining was studied by using finite difference numerical simulation(FLAC8D)method.The mechanism of rock burst in the coal seam thickness variation zone in steeply inclined coal seam by horizonal sectional mining method was revealed and the prevention and control measures were put forward.The research results show that when the thickness of the coal seam changes,the high stress near the two roadways gradually concentrates in the change area of the coal seam thickness,until it is transferred to.the roof of the return airway,and the maximum value can reach 40 MPa,which is easy to lead to the rock burst in the roof of the return airway.The research results are in agreement with the field meas-urement.