Plasticity models for the biaxial behaviour of concrete at elevated temperatures, Part II: Implementation and simulation tests

The thermo-mechanical behaviour of concrete at elevated temperatures under multiaxial stress is extremely nonlinear. In Part I we developed a general analytical failure criterion based on the available biaxial test data. Here, the loading surfaces are used to derive the elastic-plastic incremental stress-strain relationships for a plasticity approach, and the model is used to predict experimental strain measurements under biaxial stress. Agreement is shown to be very good. The predictions are also used to suggest possible variations in material parameters such as Poisson's ratio, for which scant data exist