连续排水边界下一维固结不排水对称面的有限元分析

连续排水边界可以修正边界透水与不透水这两种极端理想化的边界问题.在Terzaghi一维固结理论的基础上,结合连续排水边界给出了连续排水边界下不排水对称面一维固结的解析解答.基于ABAQUS有限元软件开发了一维连续排水边界条件的子程序,对不排水对称面位置变化的影响因素包括边界透水性能,排水时间和渗透系数进行研究,得到了不排水对称面的变化规律.最后将该数值分析方法引入饱和软黏土中不同深度设置排水砂层进行比较,结果表明在不排水对称面位置处设置排水砂层时土体的固结速度是最快的.连续排水边界的引入有利于确定不排水对称面的位置,所得的结论和文中的有限元分析过程对促进固结理论的发展具有重要的实际价值和意义.

Finite element analysis of one-dimensional consolidation of undrained symmetry plane under continuous drainage boundary

The continuous drainage boundary can correct the pervious and impervious boundaries which are extremely idealized. Based on the Terzaghi’s one-dimensional consolidation theory and the continuous drainage boundary; an analytical solution of one-dimensional consolidation of undrained symmetry plane under continuous drainage boundary is given. One-dimensional subroutine of continuous drainage boundary is written based on the finite element analysis of ABAQUS. The influence factors of undrained symmetry plane is studied; including boundary permeability; drainage time and permeability coefficient. The variation of the undrained symmetry plane is obtained. Finally; the location of setting sand layers at different depths in saturated soft clay is compared by the method of finite element analysis. The results show that the rate of consolidation is the fastest when the sand layer is set at the location of undrained symmetry plane. The continuous drainage boundary can help to determine the location of undrained symmetry plane. The results and the process of finite element analysis are of practical and important value and significance for the development of soil consolidation theory.