Shajihai Coal Mine of State Grid Energy Hefeng Coal and Electricity Co. , Ltd.

厚煤层综放工作面采取预掘单(双)回撤通道终采时,终采空间容易发生强矿压显现、煤壁破碎、顶板大变形而造成撤架遇阻。为研究此工况下接续面的合理终采方式,通过现场勘察、室内试验、原理对比、数值分析及实地监测的方法,进行厚煤层综放面不同回撤方式矿压显现对比研究。研究结果表明,预掘单回撤通道存在工作面超前支承压力与巷道支承压力的叠加(增高系数3.37),预掘双回撤通道在此基础上增加了与煤柱应力的叠加(增高系数3.69),自掘回撤通道则在终采期间无应力叠加(增高系数2.53)。同时,综合对比超前支承压力、最大剪应力以及主应力分区情况,得到在终采线位置自掘回撤通道的布置方式矿压显现最低。由此,建立了基于自掘回撤通道的终采工艺流程,根据顶板深孔位移监测设计了终采大断面空间的支护参数,并由预应力场模拟验证。经现场实践,实现了终采空间的有效支护和支架的顺利回撤。

During the terminal mining stage of fully mechanized top-coal caving face with pre-excavation of single(double) retracement roadway in thick coal seam, strong mine pressure behaviors appears in the terminal space, such as coal wall breaking and large deformation of roof, bringing difficulty to the support dismantlement. To study the rational terminal mining method of the continuous face under this working condition, through field investigation, laboratory test, principle comparison, numerical analysis, and field monitoring, the mine pressure behaviors of different dismantlement methods was compared. The result shows that the pre-excavation single dismantlement roadway has the superposition of the advance abutment pressure from the working face and from the roadway ( the increase coefficient is 3. 37) . On this basis, the pre - excavation double dismantlement roadways increase the superposition with the stress of the coal pillar(the increase coefficient is 3. 69), and the self-excavation dismantlement roadway has no stress superposed during the terminal mining period(the increase coefficient is 2. 53) . Meanwhile, the comprehensive comparison of the advance abutment pressure, maximum shear stress, and the principal stress zoning shows that the arrangement of the self-excavation dismantlement roadway at the terminal position has the lowest mining pressure. Therefore, the terminal mining process based on self - excavation dismantlement roadway is established. Based on the monitoring of the deep hole displacement of the roof, the support parameters of terminal mining large section space are designed and verified by pre-stress field simulation. Through field practice, the terminal mining space is effectively supported and the supports are the smoothly dismantled.

杨振,方珍珠,昌李宁,等.综放开采不同回撤方式矿压显现对比研究[J].煤炭工程,2024,56(12):67-75.