New approach for computing damage parameters evolution in plastic damage model for concrete
Rachid BAKHTI, Baizid Benahmed, Abdelghani LAIB, Mohanad Talal Alfach
Abstract
The Damage Plastic Model is one of the most widespread models used to simulate the real behavior of concrete. The high reliability of this model could be attributed to its ability to take into consideration the elastic stiffness degradation induced by plastic straining as well as the stiffness recovery effects under cyclic loading. This model has been implemented in ABAQUS under the name of Concrete Damaged Plasticity Model (CDPM). Nevertheless, the use of CDPM in ABAQUS is very sensitive due to the high complexity of the calibration process of comparing the model parameters with experimental data, particularly, the stress-inelastic strain diagrams and the damage parameters evolution. The main aim of this research is to develop a new methodology to facilitate the use of this model without the need to calibrate the stress-inelastic strain diagrams and the damage parameters evolution with experimental results. This methodology is based on Lubliner formulas to identify the stress-inelastic strain diagrams, and on Alfarah formulas to evaluate the damage parameters evolution. A new algorithm has been developed to determine the dimensionless coefficients of Lubliner and Alfarah formulas according to the Model Code recommendations. This algorithm has been implemented in developed finite element code where the results have been validated by comparing with experimental results and closed-form solutions.