大采高工作面复合关键层破断模式与矿压显现机理研究

Study on failure mode and mining pressure behavior mechanism of composite key strata in large mining height work face

针对大采高工作面矿压控制难题,利用相似模拟方法对覆岩破断特征与矿压显现机理进行研究,分析了覆岩运移特征与声发射监测信息,提出异步及同步断裂关键层破断模式,建立了相应的上覆岩层复合关键层结构模型和覆岩破断的力学条件,总结上覆岩层移动变形和破断随时间和空间的变化规律,得出关键层同步断裂是造成大采高工作面开采矿压显现强的根本原因。

Aiming at mining pressure control problem of large mining height work face, the overlying strata failure characteristics and mining pressure mechanism was studied by similarity simulation method. The overlying strata movement characteristics and acoustic emission monitoring information were analyzed. Synchronous and asynchronous key strata breaking mode were proposed, and the corresponding structural model of overlying composite key strata and mechanical condition of overlying rock strata failure were established. The regular pattern of movement deformation and failure of the key strata was obtained varying with time and space. It was concluded that synchronous key strata breaking was the basic cause of strong mining pressure appearance in work face with large mining height.