混合粒径散体岩石非线性渗流的试验研究

Experimental Study of Nonlinear Seepage in Mixed Granular Rock

由于渗流引起的动力灾害多发生在破碎岩体中,因此研究破碎岩体的渗流特性是非常必要的。利用MTS815.02岩石力学试验系统及破碎岩石渗透仪,采用稳态渗透法和轴向位移控制法测定了混合粒径的煤、煤矸石及灰岩在承压过程中非Darcy流的渗透特性,得到了渗透特性随孔隙率的变化规律。研究结果表明:混合粒径破碎岩体中的渗流为非达西渗流,混合粒径岩石在压实过程中随孔隙率φ的减小渗透率k逐渐减小、非达西流β因子变大,渗透率的量级为10-14～10-13 m2,而非达西流β因子的量级为1010～1011m-1,该研究可为解决破碎岩石渗流的工程问题提供一定的参考。

Many dynamic disasters resuhing from seepage take place in some broken rock, therefore study on the seepage properties of broken rock is very necessary. According to the method of steady permeating and the method of controlling axial displacement, MTS 815.02 rock test system and seepage instrument for broken rock was used to test properties of non - Darcy flow in the mixed grain broken coal, gangue and sandstone during being compressed, the relation rules of the seepage properties of broken rock corresponding to the porosity were obtained. The study indicated that the seepage in broken rocks is a non - Darcy flow, with the decreasing of the porosity, the permeability decreases and the coefficient of deviating from the Darcy flow increases, the obtained permeability h of the broken rock has a magnitude of 10 - 14 - 10 - 12 m2 while the non - Darcy flow coefficient β ranges from 10^10-10^11m-1. The result can provide some reference for the engineering problem of the seepage in broken rock.