Asymptotic state behaviour and its modeling for saturated sand  

作　　者：LUO Ting YAO YangPing CHU Jian 

机构地区：[1]Department of Civil Engineering,Beihang University,Beijing 100083,China [2]Department of Civil Engineering,Nanyang Technological University,Singapore

出　　处：《Science China(Technological Sciences)》2009年第8期2350-2358,共9页中国科学（技术科学英文版）

基　　金：Supported by the National Natural Science Foundation of China (Grant Nos. 10672010 and 50479001);the National Earthquake Science Item (Grant No. 200808076)

摘　　要：A new double hardening elasto-plastic model is proposed in this paper based on the existing unified hardening model (UH model). By assuming that there is part coupling effect between the plastic volumetric strain and plastic shear strain, hardening parameters consisting of a coupled and an uncoupled components are adopted in this model. A unique feature of this model is that it can describe not only the conventional drained and undrained behaviors of soil, but also the stress-strain relationships of soil under partially drained conditions which can be volumetric compression or dilation. Adopting the asymptotic state concept, simple equations for estimating the limiting stress ratio under undrained or earth pressure at rest (i.e. K0) conditions are derived. The new model is relatively simple to be adopted in practice for two reasons. First, the same soil parameters as in Cam-clay model are used except the addition of one extra parameter, the stress ratio at the characteristic state. Second, all the parameters can be determined using conventional triaxial compression tests.A new double hardening elasto-plastic model is proposed in this paper based on the existing unified hardening model (UH model). By assuming that there is part coupling effect between the plastic volumetric strain and plastic shear strain, hardening parameters consisting of a coupled and an uncoupled components are adopted in this model. A unique feature of this model is that it can describe not only the conventional drained and undrained behaviors of soil, but also the stress-strain relationships of soil under partially drained conditions which can be volumetric compression or dilation. Adopting the asymptotic state concept, simple equations for estimating the limiting stress ratio under undrained or earth pressure at rest (i.e. K 0) conditions are derived. The new model is relatively simple to be adopted in practice for two reasons. First, the same soil parameters as in Cam-clay model are used except the addition of one extra parameter, the stress ratio at the characteristic state. Second, all the parameters can be determined using conventional triaxial compression tests.

关 键 词：SAND ASYMPTOTIC state double HARDENING CONSTITUTIVE model PARTIALLY coupled 

分 类 号：TU441.4[建筑科学—岩土工程]