A thermodynamic constitutive model for undrained monotonic and cyclic shear behavior of saturated soils

作者：Zhang Zhichao; Cheng Xiaohui^*

来源：Acta Geotechnica, 2015, 10(6): 781-796.

DOI：10.1007/s11440-015-0389-5

• Constitutive model
• Cyclic hysteresis
• Cyclic mobility
• Non-equilibrium thermodynamics
• Undrained shear

Based on a non-equilibrium thermodynamic approach, this paper has established a constitutive model for saturated soils different from the classical elasto-plastic model and other thermodynamics-based models. It does not require concepts such as yield surface and flow rule. Instead, through a quantitative description of the energy in the reversible and irreversible processes in materials, the constitutive relations have been obtained theoretically. Using the elastic potential energy function, the stress is expressed as a function of elastic strain. By introducing the granular entropy and locked energy concepts, the non-elastic strain evolution is determined according to the non-equilibrium thermodynamics. The model can describe many basic mechanical properties of saturated soils under monotonic and cyclic shear loadings, such as the stress state boundary, the critical state and especially the cyclic mechanical behavior. Based on this model, the paper simulates the cyclic undrained triaxial shear tests for saturated clays and analyzes the impact of factors that include cyclic stress ratio, OCR value and cyclic stress frequency. The simulation results are compared with experimental results in order to validate the model.

• 出版日期2015-12
• 单位清华大学