Analytical and numerical modeling of the bond behavior between FRP reinforcing bars and concrete

•An analytical bond-slip model of the concrete/rebar interface is first proposed.•The identified bond-slip law is then introduced in a finite element (FE) model.•FE model is used to describe the local interface behavior during pull-out tests.•Simulated strain profiles are compared to fiber optic sensor measurements.•Good agreement is found in the interface damage domain at high load level. This study focuses on the modeling of the local bond behavior of Fiber Reinforced Polymer (FRP) reinforcing bars and the surrounding concrete. An analytical bond-slip model is first proposed to describe the interface behavior of the bars embedded in concrete. Then, the parameters of the bond-slip law are identified from experimental data of pull-out tests performed on specimens instrumented with optical fiber sensors. A specific procedure was developed to identify the model parameters. In a second step, the identified analytical law is introduced in a finite element model (cohesive zone damage model) to simulate the pull-out tests, and a complementary model calibration is proposed to account for the non-uniform stress distribution along the interface. Finally, calculated strain profiles at the bar/concrete interface are compared with the experimental profiles measured by optical fiber sensors. The proposed model is found suitable to simulate the bond mechanisms at high load levels, when there is significant interface damage. However, further development of the model is needed to accurately describe the bond stress and slip response at lower load levels and low/moderate interface damage.