多场耦合条件下岩体裂隙流动特性分析

Analysis of Flow Features in a Narrow Rock Crack in Multi-field Coupling

在岩体渗流场-应力场耦合作用下,裂隙流被处理成粗糙壁面狭窄流道中的Poiseuille流,岩面粗糙度及缝内充填物对流动的影响用裂缝的几何分形特征表述,建立了相应的耦合流动控制方程。以某工程裂隙为算例,使用基于有限元法的分离迭代格式计算了裂隙流在岩体渗流场、应力场耦合作用下的流动特性,得到了裂隙几何分形特征与裂隙流量、流动与岩体应力及裂隙宽度的数值关系。

Flow in a narrow rock crack is modeled with steady Poiseuille flow with stress-seepage interaction. Influences of filled maters in crack and roughness of rock wall surfaces on the flow are described with geometrical fractal characteristics of the rough rock surfaces. Numerical computation is realized with a computing code on the FEM iterating scheme in turn. A true crack from a hydropower project is taken as an example, and the numerical relationships between the fractal dimension of rock surfaces and the seepage,the stresses and the fractured breadth of the crack are obtained. The results show that the interaction of stress-and seepage-fields has a significant influence on the flow in a narrow crack passage.