不同岩性顶板回采工作面矿压分布规律

采用数值模拟技术和现场矿压观测系统,研究了不同岩性顶板回采工作面矿压分布规律及其显现特征。结果表明,在煤炭开采过程中,不同岩性顶板回采工作面最大支承应力存在一定差异,在强度较高的砂岩顶板岩体中,支承压力大,工作面前方支承压力峰值距工作面距离小,初次来压步距和周期来压步距大,矿压显现强烈;而在强度较低的泥岩顶板区,顶板岩体不能和砂岩骨架层一样抵抗覆岩压力,且支承压力小,支承压力的峰值向回采工作面前方岩体内部推移,初次来压步距和周期来压步距小,矿压显现不明显。

Distribution of underground pressure for Working face under different lithological characters of coal roof

The underground pressures of longwall face with different lithological characters of coal roof and its phenomenon are studied by using the numerical simulation technique and strata control observation.The research results show that in the progress of coal mining,there is certain difference in maximal abutment stress of longwall face with different lithological characters of coal roof.The sandstone roof with higher strength has a longer distance of initial weighting and periodic weighting,the abutment stress ahead of the working face is bigger,the distance between the peak position of the abutment stress and working face is smaller and the phenomenon of underground pressure is intense.It is on the contrary in case of the mudstone roof with lower strength.The distance of initial weighting and periodic weighting is shorter;the abutment stress on the working face is smaller,the peak position of abutment stress transfers to the inter of rock mass ahead of working face and the phenomenon of underground pressure is not obvious.