煤岩体中弹性比能分布的有限元计算分析

Finite Element Analysis for the Distribution of Elastic Specific Energy in Coal and Rock Mass

冲击地压发生的前提是矿山井巷和采场周围的煤岩体中储存了足够的弹性能.摸清围岩体中弹性能的分布规律是有效地进行冲击地压预测预报的前提,文中探讨了井巷和采场围岩体处于弹塑性变形状态下其弹性比能的计算方法,提出了用有限元法分析计算处于弹塑性变形状态下的煤岩体中弹性比能分布的理论与方法,以及产生冲击地压的弹性能判据.结果表明,煤层巷道两帮煤体中弹性比能的最大值与采深的平方近似成正比,与其弹性模量近似成反比.对鲁村煤矿2217区段运输平巷的具体条件进行的有限元计算分析表明,该巷道不满足产生冲击地压的条件,与现场实际情况相吻合.

The prerequisite of rock burst occurrence is that the elastic energy in coal and rock mass around coal mine roadway and stope has accumulated enough. The forecast of the rock burst can be made effectively when the distribution of elastic energy in surrounding rock is felt out. The calculation method of the elastic specific energy in the roadway and stope with elastoplastic state was discussed, the theory and method of calculating the elastic specific energy distribution of the rock and coal mass in elasto-plastic state using the finite element method was proposed, and the elastic energy criterion of rock burst was obtained. The results show that the maximum elastic specific energy in the wall of coal roadway is almost directly proportional to the square of digging depth and almost inverse proportional to the elastic modulus. The finite element analysis on the elastic specific energy of Lucun coal mine＇s 2217 haulageway indicate that the rock burst is impossible to occur in this haulageway, which is well agree with the practical case.