Fem Based Strategy for Analysis of Rc Structures : Application to exterior joints

Modelling the mechanical behaviour of RC structures and, in particular, the steel-concrete interaction is one of the most difficult challenges of structural engineering. The lack of a robust and objective strategy for analysis of RC structures has discouraged the use of finite element method even for discontinuous regions of structures like beam-column joints where standard methods of analysis are no longer valid. The modelling strategy based on finite element method, presented in this work, is able to consider the confinement effect of the concrete on the bond behaviour of the reinforcement in a simple and effective way. The FE model can be generated, without any user's discretionary intervention, fixing the finite element characteristic length and knowing at least the concrete compressive strength as material property. It provides structural engineers with a powerful tool to check the safety of weak components of RC structures, even of those currently designed in accordance with building codes formulas. Parametric studies can be carried out aiming to provide guidelines for design, as shear reinforcement requirements, without the need of much experimental work.