高韧性顶煤难冒性机理研究

Study on mechanism of difficult caving of highly tough top coal

为了解决高韧性顶煤的冒放性较差的问题,对其难冒性机理进行研究是非常重要的.通过理论分析,获得了高韧性煤层煤体在破坏前的挠度与弹性模量成反比,与抗拉强度成正比的关系,并得出挠度较大的顶板不能很好把支承压力传递给顶煤的结论。同时通过数值模拟计算,表明了顶煤的弹性模量对其悬顶距离和应力有很大影响,高韧性顶煤悬顶距离小,应力大,不利于顶煤体的破坏。

To solve the problem of the relative difficulty in roof caving in highly tough top-coal, it is very important to study the mechanism of difficult caving of highly tough top coal. Through theoretical analyses in the article, the highly tough top-coal deflection before destroying is in inverse proportion to elastic mould, in direct proportion to tensile strength, and the conclusion that bigger deflection roof can＇t sufficiently transmit the compressible support to top-coal is drawn. Through numerical simulation at the same time, the elastic mould of highly tough top-coal has great influence on the roof hanging distance, and the roof hanging distance is small, and stress is great, which is unfavorable to the destruction of the highly tough top-coal.