不同孔隙率下破碎灰岩渗透特性试验研究  

Experimental Study on the Seepage Properties of Broken Limestone at Different Porosity Rate

作　　者：李顺才[1] 

机构地区：[1]徐州师范大学机电工程学院,江苏徐州221116

出　　处：《徐州工程学院学报（自然科学版）》2009年第1期17-24,共8页Journal of Xuzhou Institute of Technology(Natural Sciences Edition)

基　　金：江苏省自然科学基金(BK2007029)

摘　　要：由渗流引起的动力灾害事故多发生在破碎破裂岩体中,因而如何控制渗流作用下的围岩稳定性则是采矿工程中的基础研究课题之一.利用MTS815.02岩石力学试验系统及破碎岩石渗透仪,基于稳态渗透法研究了3种不同粒径的破碎灰岩的渗流特性随孔隙率的变化规律.研究表明,水在破碎灰岩中的渗流为非达西渗流,孔压梯度与渗流速度之间可用二次多项式拟合;随着孔隙率的减小,渗透率总的趋势减小,而非达西流偏离因子增加;破碎灰岩的渗透率量级为10-14～10-13m2,而达西流偏离因子的量级为1013～1014kg·m-4.该研究成果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 resulting from flow take place in some broken or cracked rocks, therefore controlling of the stability of the surrounding rock under the flow is one of the basic subjects in mining engineering. The permeability of the broken rock is determined by its porosity. Using the MTS815.02 Rock Test system and seepage instrument of broken rock and the steady-state seepage method, the laws of seepage properties varying with the porosity are studied for the broken limestone with three kinds of grain sizes. The study indicates that the seepage in broken rock is a non-Darcy flow, and the relation between its pore pressure gradient and the flow velocity can be fitted with a binominals. With the decreasing of the porosity, the permeability decreases and the coefficient of deviating from the Darcy flow increases. The magnitude of the permeability of broken limestone is from 10^-14 m^2 to 10^-13 m^2 , and the magnitude of the coefficient of deviating from the Darcy flow is from 10^13 kg· m^-4 to 10^14 kg·m^-4. The result can provide some reference for the engineering problem of the seepage in broken rock.

关 键 词：破碎灰岩 非达西渗流 孔隙率 

分 类 号：TU452[建筑科学—岩土工程]