Fundamental thermodynamic concepts for the constitutive modeling of damaged concrete

Many damage models has been developed to express the degradation of materials. However, only minor damage model for concrete has been developed because of the heterogeneity of it unlike metals. To model the damaged behavior of concrete, this peculiarity as well as a load-induced anisotropic feature must be considered. In this paper, basic concepts of the thermodynamic theory is investigated to model the behavior of the damaged concrete in the phenomenological viewpoint. And the general constitutive relations and damage evolution equations are investigated too.