A Dynamic Constitutive Damage Model Considering Rate-Dependence of Micro-cracks Evolution for Concrete

Abstract:

In this paper， a rate-dependent damage model was proposed by incorporating micro-inertia and micro-viscosity into the static elasto-plastic damage framework to account for the strain rate effect of concrete induced by the rate-dependence of micro-cracks. The stress-strain curves and dynamic increase factors of concrete strength obtained by numerical analysis indicate that the dynamic mechanical properties of the material at moderate and high strain rates can be well captured by the model. Furthermore， numerical simulations of a Hopkinson-bar test were performed and the analytical results were in good agreement with the experimental results， demonstrating the validity of the proposed model for the dynamic responses analysis of concrete structures exposed to high-rate loadings.

Key words:concrete;dynamic;damage;rate-dependence