考虑非Darcy渗流和自重应力的一维固结分析

基于饱和黏土中渗流的非Darcy特性和变形的非线性,考虑土体埋深和自重应力的影响,修正了Terzaghi 1维固结方程.为简化计算,建立了以有效应力为求解对象的非线性控制方程,并采用有限差分法建立隐式差分格式对方程进行求解.探讨了综合考虑土体渗流非Darcy特性、埋深、自重应力和变形非线性时的固结特性.计算结果表明:考虑土体自重应力时的孔压消散速率和地基沉降速率都要大于不考虑土体自重时的情况;综合考虑土体自重、非Darcy渗流特性和变形非线性的孔压消散速率和地基沉降速率都可能出现前期快于Terzaghi固结理论解而后期相反的情况.

One dimensional Consolidation with a Consideration of Non Darcy Flow and Self gravity Stress

Based on the non-linear deformation of saturated clay and the non-Darcy flow in the soil,Terzaghi’s one-dimensional consolidation equation was modified and generalized by taking into account of the effects of the buried depth and self-gravity stress of soil layer.The effective stress was set as the dependent variable of the presented nonlinear consolidation equation,and a numerical analysis was made with the finite difference method.The effects of the parameters of the non-Darcy flow,the compressibility index of the soil,the buried depth and the self-gravity stress of soil layer on the consolidation process were investigated respectively.The numerical results indicated that both of the pore pressure dissipation rate and the settlement rate with a consideration of the self-weight stress of soil layer are greater than those without consideration.In addition,they are likely greater than the theoretical values of Terzaghi’s theory in the early period of consolidation while possibly less in the following period when all the parameters are taken into account.