坚硬覆岩破断及其对矿压显现的控制

 以同忻矿石炭系3-5 煤层8015 工作面为例,分析了坚硬覆岩破断特征及其对煤层工作面矿压显现的控制作用。应用关键层理论确定工作面坚硬覆岩的关键层及关键层的初次破断距和周期破断距,基于材料力学理论导出关键层破断与工作面支承压力的关系式,分析关键层破断对煤层工作面矿压显现的影响规律。结果表明,煤层工作面坚硬覆岩存在亚关键层I、亚关键层II 和主关键层,3 个关键层的破断导致工作面产生大小周期压力和复合压力,其中主关键层破断造成工作面矿压范围较大;理论分析方法揭示的矿压显现规律与现场矿压监测结果具有较好的一致性。

Fracture of hard overlying strata and its control of strata pressure behavior

This paper studies the fracturing characteristics of hard overlying strata and its control of the strata pressure behavior of the working face based on working face 8015 of coal seam 3-5 of the carboniferous system in Tongxin mine. The critical layer of the working face was determined as well as the initial and cycle fault displacement using critical layer theory. The relationship between critical layer facture and support pressure of the working face was derived based on theory of mechanics of materials to analyze the influence of critical layer facture on the strata pressure behavior of the working face. The results show that the working face of the hard overlying strata had sub-critical layer I, sub-critical layer II, and a main critical layer, the fracture of which led to generation of cycle pressure and complex pressure at the working face, and fracture of the main critical layer led to a relatively large range of pressure. These strata pressure behaviors derived by theoretical analysis are consistent with practical pressure monitoring.