砂岩峰后卸除围压过程的渗透性试验研究  

EXPERIMENTAL STUDY ON PERMEABILITY OF SANDSTONE DURING POST-PEAK UNLOADING OF THE CONFINING PRESSURE

作　　者：李小琴[1] 李文平[1] 李洪亮[1] 孙如华[1] 

机构地区：[1]中国矿业大学资源与地球科学学院,徐州221008

出　　处：《工程地质学报》2005年第4期481-484,共4页Journal of Engineering Geology

基　　金：国家自然科学基金资助项目(No.40272114)

摘　　要：为了探讨煤层开采引起的围岩卸除围压过程中砂岩渗透性的变化规律,本文用数控瞬态渗透法在电液伺服岩石力学试验系统MTS815.02上进行了砂岩试样的渗透特性试验。得出了试样峰前渗透系数-应变与应力-应变的关系曲线,以及在峰后保持轴向应变一定卸除围压过程中试样的渗透系数-围压与主应力差-围压的关系曲线;对试验砂岩在变形破坏过程中渗透性变化规律进行了总结,重点分析了其峰后卸除围压过程中渗透性的变化规律;并对试验砂岩峰后渗透系数与有效围压关系进行了拟合,得出了拟合方程式,为煤层开采引起的围岩体应力场与渗流场耦合问题提供参考。In order to understand the permeability of surrounding rock during post peak unloading of the confining pressure caused by coal mining, the authors conducted permeability test of sandstone using instantaneous permeating method with the electro - hydraulic servo controlled rock mechanics testing system （ MTS - 815.02 ）. The curves of permeability - axial strain and stress - axial strain before the peak point were obtained. The curves of permeability- confining pressure and principal stress difference -confining pressure during post -peak unloading of confining pressure under a constant axial strain were also obtained. The permeability of sandstone during post - peak unloading of the confining pressure was evaluated by fitting relationship curve of the post - peak permeability - effective confining pressure. The results provide guidelines for solving the problem caused by coupling stress field and seepage field of rock mass in underground engineering.

关 键 词：峰后卸除围压 渗透特性 渗透性-有效围压关系 试验研究 

分 类 号：TD322.5[矿业工程—矿井建设] O357.3[理学—流体力学]