Finite element modeling of the composite action between hollowcore slabs and the topping concrete

• Nonlinear 3-D finite element analysis for composite hollowcore slabs is presented.
• Staged construction of the topping concrete was included.
• Results of the proposed analysis were validated using experimental data.
• Interfacial shear and peel stresses nonlinear behaviour of was captured.

The ultimate strength of hollowcore slabs is greatly affected by their post-cracking behaviour. The composite action between the concrete topping and the hollowcore slab adds another level of nonlinearity. This paper presents a comprehensive finite element study to evaluate the nonlinear properties of the interface between a hollowcore slab and its concrete topping. The presented finite element modeling procedure was validated using data from a previous comprehensive experimental study by the authors. The nonlinear material behaviour of the concrete and the prestressing strands were also accounted for. The paper presents a modeling method that realistically simulates the staged construction technique of composite hollowcore slabs. Finite element results allowed understanding changes to the interface properties due to the confining effect of the applied load as well as the interaction between the shear and peel stresses.