Numerical Modeling of the Behavior of the Steel-Concrete Interface Contribution by Extended Finite Element Method (X/FEM)

Abstract

In the reinforced concrete study, the concrete steel connection is a key element» in the behavior of this composite because it will allow the transfer of forces between steel and concrete. The understanding of this phenomenon and its inclusion in the numerical analysis of reinforced concrete structures are the main objects of this research work; the approach suggested for modeling this problem is the extended finite element method (X FEM) that allows the introduction of the interface independently by the mesh. Steel and concrete bond has been studied through a pull-out test as recommended by RILEM. This work provides some ideas about the adhesion’s behavior, thus an experimental campaign was carreid out, measuring the concrete’s andsteel’s constraints and sliding over concrete. The bond stress –slip curve shows a similar behavior between experimental and theoretical results. The obtained results show the improvement of the adhesion constraint according to the increase of concrete compressive strength. Indeed, the transmission of forces between reinforcement and concrete enclosing it gives rise to a relatively complex state of stress. This paper presents a stabilized formulation for 3D contact problems, in the framework of X-FEM. It is shown that the choice of a simple algorithm and the type of mesh (concrete - steel bond) is a good solution for the determination of the adhesion behavior.