井工转露天采空区煤柱承载能力计算

Calculation of coal pillar bearing capacity in goaf when underground mining is changed to open-pit mining

以国能神东煤炭集团某矿为工程背景,由于井工开采期间采用房柱式采煤方法,造成大面积的地下采空区。转为露天开采后,采空区上部岩层被逐步剥离,覆岩安全承载能力逐渐减小,采空区塌落,重型设备掉入造成机毁人亡的安全隐患时刻威胁着安全生产。通过使用极限强度理论、威尔逊理论、单向应力法对采空区遗留煤柱的稳定性进行计算,分析230 t的采煤设备在其上部作业时采空区煤柱是否处于稳定状态,最后使用FLAC^(3D)软件对结果进行模拟,验证前面的计算结果,在实际开采过程中取得了巨大经济与安全效益,对其它类似煤矿采空区资源安全回收具有一定的借鉴作用。

In a mine of Shendong Coal Group,a large area of underground goaf is formed by the room pillar mining method during underground mining.After the open-pit mining is adopted,the upper strata of the goaf are gradually stripped,the safety bearing capacity of the overburden is gradually reduced,and the potential safety hazard of equipment damage and human death caused by heavy equipment falling into the goaf threatens the safety production all the time.By using limit strength theory,Wilson theory and one-way stress method,the stability of gob coal pillar when 230 t coal mining equipment works on the upper part of gob coal pillar is analyzed.Finally,the results are simulated by FLAC^(3D) software to verify the previous calculation results.Great economic and safety benefits have been obtained in the actual mining process,which can be used as a reference for the safe recovery of goaf resources in other similar coal mines.