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

• 来源期刊: 中国科学:技术科学（英文版）
• 年，卷（期）: 2020,（2）
• 页码范围: 303-318
• 页数: 16页
• 语种: 英文

摘要

A new method is presented to develop the existing elastic-plastic constitutive model into an elastic-plastic-viscous one for clays.The 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.