基于裂隙变形特性的岩体裂隙应力与渗流耦合试验研究

项目名称： 基于裂隙变形特性的岩体裂隙应力与渗流耦合试验研究

项目编号： No.50809069

项目类型： 青年科学基金项目

立项/批准年度： 2009

项目学科： 建筑科学

项目作者： 刘才华

作者单位： 中国科学院武汉岩土力学研究所

项目金额： 20万元

中文摘要： 本项目以当前岩体水力学领域的研究热点"裂隙岩体固液耦合问题为研究对象，通过一系列的裂隙岩体变形、渗流试验，结合理论分析，探讨了法向应力、侧向应力作用下岩体裂隙的变形特性，在此基础上，结合岩体裂隙渗流相关理论，研究复杂应力条件下岩体裂隙渗流特性及其耦合模型。研究结果表明，法向应力作用下，裂隙开度减小，裂隙法向变形量随法向应力的增加呈指数函数关系变化，符合结构面法向闭合变形法则，在侧向应力作用下，裂隙开度增加，裂隙法向变形增加量与侧向应力的关系同样符合指数函数关系，试验结果与理论分析具有很好的一致性，据此建立了三轴应力作用下裂隙法向变形与应力的耦合模型，在此基础上结合渗流达西定律，建立了基于裂隙变形特性的岩体渗流与应力耦合模型；裂隙渗透系数与法向应力呈负指数形式关系，随着法向应力的增加逐渐趋向一稳定值，而与侧向应力和渗压呈正指数形式关系，通过基于裂隙变形特性的裂隙岩体应力与渗流耦合模型对试验数据进行拟合分析表明，试验结果与耦合模型具有很好的一致性，最终建立了三维应力作用下裂隙渗流与应力耦合模型。本项目的研究结果对岩土工程的渗控及其安全性问题提供理论支持和解决方法。

中文关键词： 裂隙岩体；渗流；应力；变形；耦合模型

英文摘要： The project was focused on stress and seepage coupling properties of jointed rock mass, which is a key issue in rock mass hydromechanics. Based on a series of deformation and seepage tests of rock fractures and combined with theoretical analysis, deformation behaviors of rock fractures subjected to normal and lateral loads were discussed. Then, seepage properties of a rock fracture were investigated. The results indicates that the fracture aperture decreases with the normal stress increasing and that the normal deformation has an negative exponential function with the normal stress. It is also shown that the aperture increases with the lateral stress rising and that the exponential function can be applied to describe the relationship between the normal defromation and the lateral stress. As a result, a deformation formulation of a rock joint is put forward and a 3D-stress seepage coupling model is developed. The seepage testing results show that the hydraulic conductivity decreases with the normal stress increasing but increases with the lateral stress or the seepage pressure rising and that the 3D-stress seepage coupling function can well fit the testing data. Finally, a coupling model, describing the 3D-stress and seepage coupling properties of a rock fracture, is developed. What was gained through this research is significant for seepage control and safety of rock engineering.

英文关键词： jointed rock mass; seepage; stresses; deformation; coupling model