Multicomponent Model of Reinforced Concrete Joints for Cyclic Loading

Efficient simplified models are available for reinforced concrete beams and columns, with the assumption of a perfectly rigid connection. However, interior beam/column joints have been shown to be the area of strong deformation and degradation mechanisms, involving mainly the cyclic behaviors of concrete under shear and of bond under push-pull loading. In this paper, a global component-based model is proposed for the beam/column connections of reinforced concrete frame structures that can be directly connected to beam elements. This model incorporates explicitly the modeling of concrete, steel, and steel/concrete bond. Thus, the key mechanisms of deformation and degradation of the connection, as well as various interactions can be taken into account naturally. In particular, the effect of push-pull-type loading on the flexural steels can be captured. On the basis of a local finite-element modeling of the connection, simplifying assumptions are proposed and implemented leading to the component-based model. Both approaches (local and component-based) are compared on an application example.