Once all components of the model were properly positioned together into the assembly, appropriate interaction and constraint conditions were defined among the various components. The surface-to-surface contact interaction available in ABAQUS was applied at all of the interfaces in the model. The penalty contact method, which is well-suited for general contact modelling, was chosen as the mechanical constraint formulations. The HARD contact property was used to depict the contact behaviour in the direction normal to the interface plane, while for the tangential response the PENALTY option was specified by adopting the fric- tion coefficient. The friction coefficients were assumed to be 0.45 for the normal interface between the steel and concrete compo- nents [2] and to be 0.3 for the greased interface, while the friction coefficient was taken as 0.25 for all of the other interactions. The embedded constraint was applied between the reinforcement and the concrete slab, so that the bars were embedded inside the slab by constraining the translational degrees of freedom of the nodes on the bar elements to the interpolated values of the corre- sponding degrees of the freedom of the concrete elements. The effects of the relative slip and debonding of the reinforcement with respect to the concrete slabs were ignored.