Improved FE model to simulate interfacial bond-slip behavior in composite beams under cyclic loadings

• A model for analyzing partially composite beams under cyclic loadings is proposed.
• Hysteretic material models are used in the nonlinear formulation of a beam element.
• Correlation studies between numerical results and experimental studies are conducted.
• The numerical analysis through the proposed model shows a clear pinching shape.
• The analysis assuming fully composite action represents an overestimated behavior.

This paper describes an extension of a model for simulating the bond-slip at the interface in composite beams. The model extended in this paper is intended to simulate the non-linear cyclic behavior of composite beams on the basis of a beam element whose nodal degrees of freedom are lateral deflection and rotation, as in the original model. The hysteretic relations of concrete, steel, and shear connectors are used, and solution procedures including an iteration method to find a double neutral axis are introduced. Finally, correlation studies between numerical results and experimental studies have been conducted to validate the proposed model.