Abstract:
A new and relatively simple anisotropic plastic-damage constitutive model is developed to facilitate the numerical simulation of the failure of concrete structures. For better describe the different damage mechanisms of concrete under tensile and compressive loadings, two different damage evolution equations, being suitable for determining the anisotropic tensile and compressive damage variables, are established. Moreover, the strain equivalence hypothesis is used to assume that the strains in both the effective and nominal configurations are equal. Through this method, the deducing process of the model can be simplified, and the effective stress calculation and the damage evolution are able to be implemented by a decoupled algorithm. Thusly, the plastic part of the model can be implemented implicitly, and the damage part and nominal stress calculation can be implemented explicitly, which is convenient for numerical implementation. The model response is compared to a wide range of test results. The results show that the model is able to describe the nonlinear behavior of concrete in three-dimensional stress state well. The simulation of double-edge-notched (DEN) specimen shows that: the model can reflect the characteristics of concrete damage anisotropy. The results are more consistent with the actual situation, and the computational efficiency is also higher than that of the concrete damage plasticity (CDP) model provided by ABAQUS software.