AN ANISOTROPIC DAMAGE MODEL FOR SIMULATING THE HYSTERETIC BEHAVIOR OF CONCRETE UNDER CYCLIC LOADING

A modified anisotropic damage model is developed by introducing two independent damage evolution rules to simulate the distinct behaviors of concrete due to tensile cracking and compressive crushing. Herein, the hysteretic behavior under cyclic loading is modeled using nonlinear unloading-linear reloading stress branches. The calibrating method of key parameters is also proposed. Subsequently, the model is used to analyze the response of concrete under cyclic tension and tensile-low compressive load. The stress-strain curves calculated by the model are highly comparable to those obtained by the tests and they reflect the damage-induced stiffness degradation, accumulation of residual deformation, hysteretic energy dissipation and stiffness recovery effect due to crack closing. The numerical results show that the modified damage model is applicable to simulating the nonlinear behavior of concrete under cyclic loading.