A REEXAMINATION ON CALIBRATION OF CYCLIC CONSTITUTIVE MODEL FOR STRUCTURAL STEELS

Exquisite calibration of model parameter is crucial for simulation accuracy of cyclic constitutive model. This paper is aiming to clarify the influence of different calibration factors on the calibration results and simulation performances of Chaboche combined isotropic/kinematic hardening constitutive model. The influencing calibration factors include the definition of proof strength point on unloading-reloading path, the definition of unloading elastic modulus, the relative proportion of initial back stress and saturation back stress. Based upon different influencing factors, the Chaboche model parameters of LYP225 steel and Q460 steel are calibrated. Accordingly, the main cyclic behavior curves, including the hysteretic stress-strain curves, the evolutionary curves of stress amplitude and plastic work are simulated. Through analyzing the errors between experimental and simulated results, rational suggestions for the valuation of each influencing factor are provided. By taking these suggestions, the calibration of model parameters are able to yield favorable simulation performances and promising convenience for subsequent comparative studies.