条带法在底板承压水上采煤中应用的数值模拟研究

近年来,条带法被用来作为承压水上采煤的主要采煤方法。针对承压水上采煤问题,应用流固耦合原理,将孔隙介质中孔隙压力与应力建构在统一的本构模型中,平行计算应力场与渗流场,其实质是煤岩体体积应变对孔隙的影响通过流动本构定律加以反映;反之孔隙压力的变化可引起煤岩体变形。应用FLAC有限差分软件对条带式和长壁式采煤方法的应力发展和岩体破坏情况进行模拟并进行比较分析,证明条带法在降低由采动引起的应力影响范围和程度,从而减小煤层底板破坏程度和范围(主要是深度)的有效性,为合理确定承压水上采煤的开采方案提供了理论依据。

RESEARCH ON THE NUMERICAL SIMULATION OF STRIP METHOD IN CAOL MINGING ABOVE CONFINED AQUIFER

Strip method was used as main mathod in caol minging above confined aquifer in recent years. According to the problem of minging above confined aquifer,the paper constructed the pore pressure and the stress in porous media in a unified constitutive model,calculated Stress Field and Seepage Field parallel,the essence is effect of volume strain of rock on pore pressure be reflected by flow constitutive law;on the other hand change of pore pressure aroses rock deformation.Used finite difference method,call motion equation first,derive the new velocity and displacement by stress and outer force,then derive strain rate by velocity and derive new stress by strain rate.The paper used the finite difference software,FLAC,to make a comparative analysis between the development of stress and the destruction state of the rock in longwall caving ore method and strip method,which proved the effectiveness of strip method to decrease the influence degree and range of stress induced by coal mining as result of decreasing the destructive degree and range of the coal seam floor(mainly refer to depth).The paper provided the base for determination mining methods in reason above confined aquife.