Evaluation of RHT model for modeling concrete in numerical simulation

This study investigates the ability of the RHT model in representing concrete material in numerical simulation analysis. The RHT model as implemented in the hydrocode Autodyn is examined through a series of single-element numerical tests for various loading conditions. The observed stress-strain relationships from these tests tend to show some shortcomings of the model with the default parameter settings, such as a generally slow softening branch. New settings for the relevant model parameters are proposed and with these proposed parameter values the RHT model is found to be able to achieve much improved representation of the constitutive behaviors of concrete for most loading scenarios. It is also found that there are some inherent limitations in the current framework of the RHT formulations. Finally, a typical numerical example is given to demonstrate the performance of the RHT model in the numerical simulation of concrete structures under complex high rate loading.