Stiffness and Deflection of Steel–Concrete Composite Beams under Negative Bending

Compared with simply supported beams, continuous steel–concrete composite beams have many advantages such as higher span/depth ratio, less deflection, and higher fundamental frequency of vibration due to its higher stiffness. However, in negative bending regions near interior supports, tension in concrete is unfavorable and a complicated issue, which deserves a special study. In this paper, a mechanics model based on elastic theory was established to investigate the stiffness of composite beams in negative bending regions by considering slips at the steel beam–concrete slab interface and concrete–reinforcement interface. In order to validate this approach, a test of three composite beams with profiled sheeting under negative bending was conducted. Meanwhile, a three-dimensional nonlinear finite element (FE) analysis was conducted to investigate the general behavior of the tested specimens. In addition, a comparative analysis between results derived from the analytical model, laboratory test, and FE analys...