大理岩剪切裂隙渗流特性

Seepage characteristics in shear fracture of marble

针对高水头抽水蓄能电站、高坝枢纽工程和深埋隧洞工程的建设和运行中,由于高水压造成的突涌水及岩体失稳问题,以大理岩为例,研究了大理岩剪切裂隙渗流规律.试验结果表明:径向渗流试验中,渗流过程符合达西定律,水头压力与流量呈线性关系;裂隙面中局部张拉破坏的特征对渗流起到了阻碍作用;法向力对裂隙渗流的影响显著,在法向应力从14 MPa升至19 MPa过程中,渗流通道随法向力的增加出现了闭合现象,裂隙中形成了大面积死水区,渗流特性表现出突变.

In view of the problems of water inrush and rock mass instability caused by high water pressure in the construction and operation of high head pumped storage power station,high dam project and deep buried tunnel project,marble was taken as an example to study the law of shear fracture seepage in marble.The test results show that in the radial seepage test,the seepage process is in accordance with Darcy’s law and the hydraulic pressure is linearly related to the flow rate;the characteristics of local tensile failure on the fracture surface hinder the seepage;the normal force has a significant influence on the seepage of fracture surface.In the process of increasing the normal stress from 14 MPa to 19 MPa,the seepage channels get closed with increasing the normal force,a dead zone formed in the fracture,and the seepage flow characteristics change abruptly.