Analytical Solution for Bending Deformation of Steel–Concrete Composite Beams Considering Nonlinear Interfacial Slip

This study proposes a closed-form explicit, exact analytical model for bending deformation accounting for the interface nonlinearity in regular steel–concrete composite beams with partial shear connectors. A nonlinear shear load–slip equation that facilitates theoretical derivation and numerical simulation analysis was introduced to consider the nonlinear effects of partial shear interaction on composite structures. Applying the principle of minimum potential energy and the variational principle, a theoretical model was then proposed for the bending deformation and interface slip of a simply supported steel–concrete composite beam under varied load conditions. Using a trigonometric series, slip displacement and bending deflection functions were devised based on the undetermined coefficient method. A unified solution was also proposed for the beam’s bending rigidity, taking into account nonlinear interface slip. The analytical solutions’ applicability and accuracy were validated by comparing with existing experimental literature. Furthermore, a parametric study using the validated numerical nonlinear model demonstrated the influences of the stud spacing, the nonlinear interfacial effect, and the span-to-depth ratio of composite beams. This research can be referred to the accurate deformation estimation of composite beams.