Description of thermo-mechanical behaviour of reinforced concrete

In this paper a mathematical framework is outlined for modelling the thermo-mechanical behaviour of reinforced concrete. The formulation is an extension of recent work of the present authors (2002). The constitutive model is developed by employing simple volume averaging schemes for the macroscopic stress/strain rates. Both, a homogeneous deformation mode (prior to cracking) as well as a localized mode, associated with formation of macrocracks, is considered. In the latter case, the representative volume comprises the reinforced fractured zone and the “intact material”. The stiffness of the reinforcing network is evaluated by considering the individual steel bars to be rigidly embedded in the adjacent concrete matrix. Numerical examples are provided illustrating the performance of the proposed framework under the mechanical loads as well as the thermal gradients.