Flexural Behaviors of Prefabricated Composite Beams with Segmented Precast Concrete Slabs

The flexural behaviors of prefabricated steel-concrete composite beams (PSCCBs) with segmented precast concrete (PC) slabs were investigated through four-point bending tests. Experimental results showed that all the tested PSCCBs failed in flexural failure. The PSCCBs with segmented PC slabs exhibited good deformability and ductility, and the displacement ductility coefficient was not less than 13.3; the ultimate load-carrying capacity of the beams decreased by 8.7% when the shear connection degree reduced from 1.0 to 0.65. Three-dimensional finite element (FE) models were developed to evaluate the influence of parameters, such as the gap width (GW) between adjacent PC slabs and the length of the middle PC slab (LM), on the flexural behaviors of PSCCBs. Numerical results showed that the LM and GW are tightly correlated with the flexural behaviors of PSCCBs with segmented PC slabs, but their effect on the ultimate load-carrying capacity is negligible. A prediction method for the mid-span deflection of PSCCBs with segmented PC slabs was proposed based on the numerical analyses. The comparisons show that the theoretical and numerical results agree well with each other. The proposed method could be used for the preliminary prediction of the mid-span deflection of PSCCBs with segmented PC slabs when the design load is no more than half of the load-carrying capacity.