To adequately simulate the behavior of concrete exposed at high temperature, a new constitutive model was proposed. The particularity of our model is the fact that dehydration is considered as chemoplastic softening. Whereas traditional methods adopt conventional models of elastoplasticity…
To adequately simulate the behavior of concrete exposed at high temperature, a new constitutive model was proposed. The particularity of our model is the fact that dehydration is considered as chemoplastic softening. Whereas traditional methods adopt conventional models of elastoplasticity and try to vary certain parameters dependent on local temperature. Under chemoplastic framework, we also proposed a new yield criterion which was experimentally fitted. To realistically reproduce the impact of high temperature on concrete durability under different loading modes, new ductility function was proposed and fitted to a wide range of dehydration processes. The hardening and softening functions are defined in terms of the acting confining pressure. The inelastic dilatancy of concrete is expressed through the non associate flow rule. In this fact, new chemoplastic potential was proposed and fitted to ensure better estimate of the load directions. The prediction capabilities of the model are demonstrated and numerical predictions are compared with experimental results. The comparison reveals that the model accurately predicts different stress states of concrete under different temperature treatments.