A coupled chemoplastic-damage constitutive model for plain concrete subjected to high temperature

A coupled chemoplastic-damage constitutive model for the simulation of coupled chemo-thermo-hygro-mechanical behavior of concretes at high temperature is proposed. A consistent return mapping algorithm for the integration of the rate coupled constitutive equations is developed. Consistent tangent modulus matrices for coupled chemo-thermo-hygro-mechanical analysis are derived to preserve the quadratic rate of convergence of the global Newton iterative procedure. Numerical results demonstrate that the proposed constitutive model in reproducing coupled chemo-thermo-hygro-mechanical behavior of concretes subjected to fire and thermal radiation is available and effective.