岩体弱面破坏对综采工作面周期来压的影响

Influence of Rock Mass Weak Surface Failure on Periodic Weighting of Fully Mechanized Mining Face

井田地层多为沉积岩,由于地质构造作用的影响,采场围岩体内存在节理、层理及断层等弱面。指出了采场岩体弱面破坏的形式,利用莫尔强度理论对弱面破坏机理进行了分析,得到了岩体弱面在采动影响下产生"活化"的条件,同时结合赵庄二号井1305综采工作面的矿压显现规律的考察研究,在岩体弱面的影响下,工作面周期来压强度降低,来压步距变小;煤壁及顶板破坏范围变大,容易出现大范围冒顶及片帮。

The strata in the mine field are mostly sedimentary rock. Due to the influence of geological tectonics, there are weak surfaces such as joints, bedding and faults in the surrounding rocks of the stope. The paper indicates the fracture forms of surrounding rock weakness face. It analyzes the weakness face failure mechanism by Mohr-Coulomb strength theory, and gets the activation condition of weak face under the influence of mining action. Meanwhile, combining the study on the strata -pressure behavior of 1305 fully mechanized working face in Zhaozhuang No.2 coal mine, the periodic weighting interval decreases and the pressure strength decreases under the influence of weak rock mass. The failure scope of coal wall and roof becomes larger, and it is easy to have a large range of roof fall and wall caving.