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This paper aims to investigate the flexural performance of a prefabricated steel–ultra-high-performance concrete (UHPC) composite deck (PSUCD) consisting of an orthotropic steel deck (OSD) and a reinforced UHPC layer under transverse hogging moment. Ten full-scale steel–UHPC composite slab specimens were subjected to four-point flexural tests, which varied shear connectors, steel reinforcement, and wet joint interfaces. The results showed that all specimens exhibited typical flexural failure with excessive opening of critical cracks in the UHPC layer. The specimens utilizing notched perfobond strip connectors (NPBLs) with perforating rebars had higher nominal cracking strength (maximum crack width of 0.05 mm) and ultimate capacity by 15% and 27%, respectively, compared to those using studs. The perforating rebars in NPBLs improved post-cracking performance, increasing nominal cracking strength and ultimate capacity by 14% and 16%, respectively. The lateral interfaces of rectangular-tooth-shaped wet joints resulted in a local weak link in PSUCDs, leading to a 17% decrease in nominal cracking strength, and as much as 26% if interfacial roughening was omitted. Increasing the diameter of surficial reinforcement from 10 mm to 12 mm improved nominal cracking strength and ultimate capacity by 20% and 17%, respectively. Considering the influence of wet joint interfaces, prediction models for maximum crack width, nominal cracking strength, and ultimate capacity were developed and validated for the performance design of PSUCDs under transverse hogging moment. • Flexural tests were performed on ten local full-scale composite slab specimens to elaborate the flexural behavior of a prefabricated steel–UHPC composite deck under transverse hogging moment. • The influences of shear connector types, presence of wet joint interfaces, and distributed reinforcement diameter on the flexural performance were experimentally identified. • Considering the impact of wet joint interfaces, simplified prediction equations for tensioned reinforcement stress, maximum surficial crack width, nominal cracking strength, and ultimate capacity were developed and verified by the test results. [ABSTRACT FROM AUTHOR]

In this paper, the structural behaviour of timber precast concrete composite (TCC) beam-to-column subassemblies subjected to hogging bending moments is investigated. Full-scale testing and analytical modelling are undertaken on timber precast concrete composite joints and beams. The composite actions were transferred via coach (lag) screw shear connectors embedded in the small grout pockets. The laboratory tests were designed to determine the influence of the size and type of timber beams (i.e., laminated veneer lumber (LVL) or glued laminated timber (GLT)), size of screw shear connectors and amount of reinforcement (in the slabs) on the structural behaviour (i.e., load-displacement, stiffness, capacity, and ductility) of the TCC beam-to-column connections. The hogging moment capacity and stiffness of the TCC floors with nominal slab thickness of 80 mm and reinforcing ratio (in the range of 0.9–1.8%) were up to 24% and 17% higher than that of the bare timber beam, respectively. The size of coach screw shear connectors (in the range of 8–16 mm) had less than 13% effect on the capacity and stiffness. An analytical model for calculating the peak load and stiffness of the TCC beams under hogging bending moment is developed. The model is shown to perform well when compared to the collected test data. • Behaviour of TCC beam-to-column connections under hogging moment is studied. • Slab reinforcing ratio had less than 24% effect on the hogging moment capacity. • Slab reinforcing ratio had less than 17% effect on the stiffness of the TCC beam. • A model for estimating stiffness & strength of TCC under hogging moment is proposed. • Full composite action increased the capacity & stiffness of the TCC by 56% and 38%. [ABSTRACT FROM AUTHOR]