基于地表变形预计的矿区保护煤柱留设方法

Method of designing protection coal pillar in mine area based on prediction of surface deformation

针对不同开采条件下地表移动角参数的不确定性和现有的矿区保护煤柱留设方法的局限性,将引起地表点移动的地下开采范围视为椭圆形区域,以受保护对象的临界变形指标为依据,应用随机介质理论的概率积分法确定影响椭圆的半轴长度。通过绘制受护边界各角点处的影响椭圆及相邻椭圆公共外切线的方法,确定建筑物保护煤柱边界。实例应用表明,该方法可依据受保护对象的保护等级要求和开采煤层厚度等因素,合理地确定各种地面工程的保护煤柱范围,提高了保护煤柱的安全可靠性。

In accordance with uncertainty of surface movement angle under the differential mining conditions and shortages of current method for designing protection coal pillar, the scope of underground mining causing surface movement is taken as a elliptic area, so the semi-axis length of the influencing ellipse is defined with critical deformation indexes of protected object based on probobility intergral method of the stochastic medium theory. The edge of protection coal pillar is defined after drawing influencing ellipse of comer points of protected scope and the common outside-tangents of all ellipses. Application example indicates that the new method, considering grade of pretected object and thickness of mined coal, can rationally defines pretection coal pillars for any ground objects, also inproves the safety and reliability of pretection coal pillars.