Bond–slip behavior under monotonic uniaxial loads

An analytical model which can simulate the bond–slip behavior between reinforcing steel and concrete is proposed. Unlike the classical bond–link or bond–zone element using double nodes, the proposed model takes into consideration the bond–slip effect without taking double nodes. After determination of the boundary condition at both ends of a reinforcing steel, the deformation of the steel at each node can be found through the back-substitution technique from the first to the final steel element using a governing equation that was constructed based on the equilibrium at each node of steel and the compatibility condition between steel and concrete. The numerical model results in an effective use in the case of complex steel arrangements where the steel elements cross the sides of the concrete elements, and second, turns the impossibility into a possibility in considering the bond–slip effect in one- and three-dimensional finite element analyses. In addition, the proposed model is applied to the bending problem using a beam element. Finally, the analytical predictions are compared with experimental results of monotonic loads and very good agreements are obtained.