A矿采场底板突水危害性分析

Analysis of Harmfulness of Water-Inrush in the Floor of A Coal Mine

根据A矿的岩层柱状图,运用RFPA2D软件计算了采场推进到25m和50m时底板岩层的应变分布,且利用渗透特性与应变之间的关系,计算了相应的底板突水因数。利用煤矿底板突水因数表述了层状岩体渗流失稳条件并判断隔水关键层位置.研究结果表明:岩层的破坏造成渗透率的增大、非Darcy流β因子和加速度系数的减小,从而使突水因数增大;随着工作面的推进,底板的破坏范围扩大,变形增大,突水因数增大;当推进到25m时,底板突水因数为95.1%;当推进到50m时,底板突水因数为619%.

Based on the column of rock mass in A Coal Mine, the distributions of stress in mining floors are simulated by using the numerical testing machine （RFPA） at the moment when longwall mining is pushed on to 25 meters and 50 meters respectively; and the water-inrush-factors are calculated on the basis of the relationship between permeability parameters and strain. A definition of water-inrush-factor is pres- ented, and the criterion about the instability of seepage flow of water in stratified rock mass is describes by water-inrush-factor. It shows that the permeability rises, the non-Darcy flow β factor and acceleration coefficient decrease as the failure of the mining floors, and the water-inrush-factor rases subsequently. As the longwall mining is pushed on, the destroyed district extends, and the strain and water-inrush-factor increase correspondingly. For the mining floor in A Coal Mine, the water-inrush-factors are 95. 1% and 619% when the working face is pushed on to 25 and 50 meters respectively.