Experimental study of seepage characteristics of single rock fracture based on stress states and stress history  

作　　者：ZHANG Chi ZHANG Yanjun LI Zhengwei ZHANG Tong LIU Tong XIE Yangyang ZHANG Chi;ZHANG Yanjun;LI Zhengwei;ZHANG Tong;LIU Tong;XIE Yangyang(College of Construction Engineering,Jilin University)

机构地区：[1]College of Construction Engineering,Jilin University

出　　处：《Global Geology》2016年第3期177-181,共5页世界地质（英文版）

基　　金：National Natural Science Foundation of China(No.41372239);Graduate Innovation Fund of Jilin University(No.2015096)

摘　　要：Through seepage tests under different loading and unloading confining pressures and different hydraulic gradients,the authors studied the effects of stress states and stress history on fracture permeability evolution for single granite fracture and sandstone fracture. The results show that there exists a linear relationship between the seepage discharge and osmotic pressure in sandstone fissure under each level of confining pressure. With the increasing in the confining pressure,the permeability of the fracture decreases,but the decreasing rate is changeing. During the unloading process,the fracture seepage velocity cannot be fully recovered to the size of the loading process. Therefore,in the unloading process of the confining pressure,the recovery of fracture permeability shows obvious hysteresis effects. The flow rate of the fracture remains unchanged during five cycles of loading and unloading processes of the confining pressure. In each cycle,the evolution character of the flow rate with the confining pressure remains unchanged. These experiments show that the seepage characteristics of sandstone and granite fractures are not the same under the same stress state.Through seepage tests under different loading and unloading confining pressures and different hydrau-lic gradients, the authors studied the effects of stress states and stress history on fracture permeability evolution for single granite fracture and sandstone fracture. The results show that there exists a linear relationship between the seepage discharge and osmotic pressure in sandstone fissure under each level of confining pressure. With the increasing in the confining pressure, the permeability of the fracture decreases, but the decreasing rate is changeing. During the unloading process, the fracture seepage velocity cannot be fully recovered to the size of the loading process. Therefore, in the unloading process of the confining pressure, the recovery of fracture per-meability shows obvious hysteresis effects. The flow rate of the fracture remains unchanged during five cycles of loading and unloading processes of the confining pressure. In each cycle, the evolution character of the flow rate with the confining pressure remains unchanged. These experiments show that the seepage characteristics of sandstone and granite fractures are not the same under the same stress state.

关 键 词：rock single fracture rock seepage stress states stress history 

分 类 号：TU45[建筑科学—岩土工程]