EXPERIMENTAL STUDY ON FLEXURAL BEHAVIOR OF STEEL-CONCRETE COMPOSITE BEAM COMPRISING PRECAST COMPOSITE SLABS

摘要

Four-point bending tests including twelve specimens were carried out to investigate theflexural rigidity, failure mode and ultimate capacity of the steel-concrete compositebeam with a composite floor slab comprising 30 mm thick precast prestressed concretepanels and T-shaped concrete ribs (PPCRP). The test parameters included supportlength of PPCRP, thickness of the composite floor slab, longitudinal compressivereinforcement ratio, degree of the shear connection and the direction of T-shapedconcrete rib. Strain distribution along the depth of mid-span section was obtained bystrain gauges. Based on the moment-deflection curves of specimens, it was showedthat flexural behavior of precast composite floor slab was similar to that of concretefloor slab cast in-situ during the elastic stage. Two failure phenomena were observed:i) Interface bond slip between the precast panel and the cast in-situ layer; ii) Diagonalshear crushing in one shear span. Compared with the floor slab cast in-situ, a slightdecline in the ultimate flexural capacity was observed for the composite beam withcomposite floor slab. Analyses about the effects of all parameters on compositebeams' rigidity and ductility were presented.