真空预压有限元计算方法研究

为进一步了解真空预压的加固机理，对真空预压时地下水位的变化情况以及边界对加固效果的影响进行了分析，并导出了考虑井阻和涂抹的双向渗流和变形的砂墙地基固结度计算公式．在有限元计算中，将殷宗泽的双屈服面模型与修正的考马拉一黄模型相结合，并改进了边界条件和初始条件的处理方法，考虑了砂井阻力的影响．工程实例表明，该分析计算方法考虑了土体的剪胀性、剪缩性和黏弹塑性，可以较好地模拟真空度在砂井和地基土中的传递规律．

Finite element method for vacuum preloading

An analysis was made on the variation of groundwater level under vacuum preloading and the influence of boundaries on the effect of consolidation for further understanding the mechanism of consolidation by means of vacuum preloading, and a formula for calculation of the degree of consolidation of sand-wall foundation was derived with the factors of sand-drain resistance, smearing, bi-directional seepage, and deformation taken into account. During the finite element calculation, the double-yield surface model, presented by Yin Zongze, was combined with the modified Komamura-Huang model, and the methods for dealing with the boundary condition and initial condition were improved. Practice shows that, with consideration of dilatancy, contraction, and viscoplasticity of soil, the present method can well simulate the transfer of the vacuum degree in sand-drain and foundation soil.