Finite difference solution to equation for large-strain consolidation of double-layered vertical drain ground
ZHANG Ming1, 2, ZHAO You-ming2, LIU Guo-nan2, HU Rong-hua3
1. Institute of Civil Engineering, Henan Institute of Engineering, Zhengzhou 451191, China; 2. China Academy of Railway Sciences, Beijing 100081, China; 3. Center for Assessment and Development of Realestate of Shenzhen, Shenzhen 518034, China
Abstract:Based on the governing equation for axisymmetric large-strain consolidation of vertical drain ground, some actual conditions are considered for double-layered sand drain ground, including nonlinear and power function variation of compressibility and permeability of soft clay, stage loading, radial and vertical drainage conditions and several kinds of distribution modes of the initial excess pore pressure. An equation for large-strain consolidation of double-layered vertical drain ground is established, and the alternation direction implicit (ADI) method of finite difference method is adopted to solve the governing equation by means of the computing program. The rationality of the established equation, the finite difference method solution and the computing program are verified through a case study. Compared with the classical consolidation theory, the consolidation settlement process of double-layered vertical sand ground of dredged fill and marine deposit silt in reclamation land projects obtained by the proposed method based on the observed data is more reasonable. A beneficial discussion of predicting the consolidation settlement process of the double-layered vertical sand ground is performed.
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