Bond slip model for the simulation of reinforced concrete structures

Abstract

This paper presents a new finite element approach to model the steel-concrete bond effects. This model proposes to relate steel, represented by truss elements, with the surrounding concrete in the case where the two meshes are not necessary coincident. The theoretical formulation is described and the model is applied on a reinforced concrete tie. A characteristic stress distribution is observed, related to the transfer of bond forces from steel to concrete. The results of this simulation are compared with a computation in which a perfect relation between steel and concrete is supposed. It clearly shows how the introduction of the bond model can improve the description of the cracking process (finite number of cracks).

Crack opening estimate in reinforced concrete walls using a steel–concrete bond model

“…Even if these approaches lead to a correct description of the bond mechanisms between steel and concrete, they also have their own limits, especially in cases of real scale applications: meshing problems (explicit representation of 3D steel geometry) or increase in computation time (with enriched elements). That is why alternative solutions were proposed [17] to represent the effects of the steel-concrete bond in a context adapted to large scale applications: truss steel elements are used for reinforcement with no need to explicitly mesh the steel-concrete interface.…”

“…But this hypothesis may have heavy consequences, especially when the crack properties (spacing and openings) are studied, as the steel-concrete bond directly influences their evolutions ( [1,11] for example). To take into account this interfacial behavior between steel and concrete in a more appropriate manner, the new interface element developed in [18], based on the previous work from Casanova et al [17], is used. It is a zero thickness four node element which relates each steel truss element with an associated superimposed segment, perfectly bonded to the surrounding concrete ( Fig.…”

Reinforcement–concrete bond behavior: Experimentation in drying conditions and meso-scale modeling

“…The obtained cracking behavior is highly dependent on the steel-concrete bond [16]. But the local behavior of the embedded rebar is often difficult to evaluate experimentally.…”

“…technique is numerically convenient, but has difficulties in capturing the progressive loss of bond stiffness during loading. We can also cite other interesting studies: (i) one is based on internal forces and kinematic relations between a truss-element rebar and plain concrete [16], (ii) an other one extends an explicit cracking model for concrete to the bond behavior, taking into account the progressive degradation in shear [17], (iii) embedded or extended finite element methods are also used on joints elements [18].…”

On the Numerical Modelling of Bond for the Failure Analysis of Reinforced Concrete

“…For perfect bond, the nodes of the reinforcement are merged with those of the concrete elements, if the mesh is generated so that the location of nodes of reinforcement and concrete elements coincide. Alternatively, the degrees of freedom of the reinforcement are constrained within the concrete elements [34,10,18,6]. Perfect bond is often assumed in the failure analysis of structures with good bond conditions between reinforcement and concrete, such as for the case of deformed reinforcement bars, which contain ribs to increase the load transfer between steel and concrete [7].…”