Analysis Of Axisymmetrical And Equivalent Plain Strain Consolidation By Vertical Drains

Researches on consolidation by vertical drains using a finite element method have been carried out for its complicated field conditions, boundary conditions and multi-ways of application of load. Especially, the plain strain finite element method has been recommended because it can reduce calculation time . Then, the key is how to transfer the three-dimensional consolidation to the plain strain consolidation. Theories of axisymmetrical consolidation, plain strain consolidation and equivalent plain stain consolidation by vertical drains have become the theoretical parts of the problem. Although many corresponding theories or methods have been put up with until now, there are still lack of systemic researches and means to discern the applicability of these methods. This paper comes out to solve those problems.Firstly, rigorous equal strain solutions of radial and vertical coupled consolidation by vertical drains under an arbitrarily distributed ground soil stress increase are proposed in this paper. This paper further attempts a series of calculation factors sensitivity and comparison of the results from those of Barron, Hansbo, Xie, Zhao, Leo, and the solution in this paper. Thus, the law of influence factors and problems have been found.Secondly, based on the present theories of plain strain consolidation by vertical drains, plain strain solutions of horizontal and vertical coupled consolidation by vertical drains subjected to a step- or ramp-loading operation under an arbitrarily distributed ground soil stress increase are carried out. Also, this paper further attempts the applicability analysis and comparison of the results from different approaches such as those of Hird, Indraratna, Zhao, Zhu , Chen Jian-feng, Liu, Chen Li-hong and the solution in this paper.Lastly, a series of calculation factors sensitivity and comparison are made among those equivalent plain strain consolidation solutions in this paper. On the base of this, those equivalent plain strain consolidation methods are simplified and compared.