Elastic visco-plastic model for soft clay based on isochronous curves
LUO Qing-zi1, CHEN Xiao-ping2, YUAN Bing-xiang1, FENG De-luan1
1. School of Civil and Transportation Engineering, Guangdong University of Technology, Guangzhou 510006, China; 2. College of Science and Engineering, Jinan University, Guangzhou 510632, China
Abstract：The deformation of soft clay is closely related to the time, including both consolidation effect and creep effect, between which the interaction determines the settlement and long-term settlement of soft soils. Based on the Bjerrum's theory of isochronous curves, an elastic visco-plastic constitutive model for soft clay is derived, which is used to replace the linear elastic stress-strain relationship of Terzaghi's consolidation theory. And with further consideration of nonlinear seepage influence, one-dimensional nonlinear governing equations which can couple the effect of creep and consolidation are established. There are 8 model parameters with concise physical meanings in this model, which can be obtained through laboratory tests easily. In addition, the Crank-Nicolson finite difference method can be used to solve the governing equations under certain boundary conditions. In order to verify the validity of the model, the calculated results by this model are contrasted with the results of oedometer tests and Leroueil and Kabbj' s CRS tests. It is shown that the calculated values are in good agreement with the experimental results.
罗庆姿, 陈晓平, 袁炳祥, 冯德銮. 基于等时曲线的软黏土弹黏塑性模型[J]. 岩土工程学报, 2018, 40(S2): 142-146.
LUO Qing-zi, CHEN Xiao-ping, YUAN Bing-xiang, FENG De-luan. Elastic visco-plastic model for soft clay based on isochronous curves. Chinese J. Geot. Eng., 2018, 40(S2): 142-146.
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