分形介质饱和渗流应力耦合数值模拟研究

STUDY ON NUMERICAL SIMULATION FOR COUPLED PROBLEM OF SEEPAGE AND STRESS IN FRACTAL MEDIA

基于介质骨架、固体颗粒以及水是可压缩的这一假设,推导出饱和的渗流应力耦合控制方程组。采用加权残值法对耦合方程组进行有限元离散,并推导相应的弹塑性矩阵。对耦合计算中的渗透系数分形模型展开讨论,综述采用分形维描述多孔介质和裂隙介质渗透系数方面研究的进展。最后,在给出的固结算例中采用一个较为实用的分形渗透系数模型,该模型可模拟渗透系数随介质变形而变化。数值计算的结果显示出良好的规律性,可以提高对耦合试验观测现象的理解。

Base on the assumption of compressible skeleton,grain and watert,he saturated governing equations are deduced.The governing equations are discredited by using Galerkin method,and the matrix for elastoplastic constitutive model is also deduced.With introduction of the fractal permeability model in coupled problem,a review of the advance on describing of the permeability by fractal method in fractal porous media and fracture media is made.Finally,a practical fractal permeability model to applied in consolidation analysist,he permeability model can simulate the permeability changing with the deformation of media.The numerical result shows good regularity,and can improve the understanding of observation made in coupled experiment.