一种双重孔隙介质水–应力耦合模型及其有限元分析

Coupled hydro-mechanical model and FEM analyses for dual-porosity media

建立了一种双重孔隙介质水–应力耦合模型,其特点是可考虑裂隙的组数、间距、方向、连通率和刚度的变化的影响,并研制出相应的二维有限元程序。在假定裂隙的渗透性与裂隙间距无关的前提下,通过算例考察了不同的裂隙间距对双重介质岩体中的变形、主应力、孔隙水压力及裂隙水压力的作用,并与单重介质岩体的相应情况作了对比。结果显示:裂隙间距对双重介质岩体的位移影响很大,但对岩体主应力及孔隙与裂隙水压力的影响很小,岩体水压力主要取决于孔隙与裂隙的孔隙率与渗透系数。

One kind of coupled hydro-mechanical model for dual-porosity media,in which the sets,spaces,angles,continuity ratios and stiffnesses of fractures can be considered,is established,and the relative two-dimensional program of finite element method is developed.Under the condition of assuming that permeability of fracture is independent of fracture space,the effects of fracture spaces on the displacements,stresses,pore pressures and fracture pressures in a dual-porosity rockmass are investigated through examples,and the cases of the dual-porosity rockmass and a single-porosity rockmass are also compared.The results show that the fracture space influences intensively on the displacements of the dual-porosity rockmass but has a small action on the stresses and pore and fracture pressures in the rockmass,and that water pressures in the rockmass mainly depend on the porosities and permeabilities of rock and fracture.