非均质饱和-非饱和土的变形特性

Deformation Characteristics of Non-homogeneously Saturated-Unsaturated Soils

利用饱和-非饱和多孔弹性介质控制方程建立有限元计算模型,考虑弹性模量随深度增加及其在水平方向的变化,分析了非饱和土中超静孔隙水压力消散和土体的变形特性.通过与相关文献结果对比可验证文中采用的计算模型的正确性.研究结果表明:土体的非均质性对超静孔隙水压力的消散和土体的变形均有显著影响;弹性模量沿深度方向变化率越大,非饱和土体吸收的压力越多,导致超静孔隙水压力消散得越快,并且初期变形阶段和固结完成后,土体的变形幅度减小.

A fully coupled numerical model was presented to analyze the process of dissipation of the excess pore water pressure and solid skeleton deformation based on the poroelastic governing equations.The numerical model was verified against a two-dimensional consolidation of homogeneous unsaturated soil.The numerical results show that the non-homogeneity has its own importance not only during the process of dissipation of the excess pore water pressure but also for solid skeleton deformation.As the gradient of soil modulus increases,dissipation rate of excess pore water pressure increases and the amplitude of the soil＇s deformation decreases in the initial compaction stage and final steady stage.