A new method of developing elastic-plastic-viscous constitutive model for clays

作     者：LU DeChun MIAO JinBo DU XiuLi LIANG JingYu LU DeChun;MIAO JinBo;DU XiuLi;LIANG JingYu

作者机构：Key Laboratory of Urban Security and Disaster Engineering of Ministry of EducationBeijing University of TechnologyBeijing 100124China 

出 版 物：《Science China(Technological Sciences)》 (中国科学（技术科学英文版）)

年 卷 期：2020年第63卷第2期

页      面：303-318页

核心收录：

学科分类：081401[工学-岩土工程] 08[工学] 0814[工学-土木工程] 

基　　金：supported by the National Natural Science Foundation of China(Grant Nos.51522802,51778026,51421005&51538001) the Natural Science Foundation of Beijing(Grant No.8161001) 

主　　题：clays constitutive model reference state line time-dependent behaviours creep strain rate 

摘      要：A new method is presented to develop the existing elastic-plastic constitutive model into an elastic-plastic-viscous one for *** actual loading process is divided into an instant process and a delayed process denoting the elastic-plastic strain and viscous strain, respectively. The elastic-plastic strain is determined by either an elastic-plastic model for overconsolidated clays or an improved model based on the elastic-plastic model for normally consolidated clays. In order to calculate viscous strain, a reference state line is defined based on the actual loading path. Combining the reference state line, an existing elastic-plastic model can be conveniently developed into an elastic-plastic-viscous model. Furthermore, using the proposed method, the modified cam clay model is extended into an elastic-plastic-viscous model. Comparisons with test results demonstrate that the extended model can capture the main time-dependent behaviours of clays, including creep, stress relaxation and strain rate effects.