Experimental studies on the flexural behaviour of steel-concrete composite beams with transverse and longitudinal hidden girders

Traditional composite beams have the problem of large self-weights and require a considerable number of structural materials. In order to address these problems, this paper focuses on a new type of steel-concrete composite beam with transverse and longitudinal hidden girders (TALHGs). To investigate the flexural performance of such beams, five specimens with TALHGs were examined. The results indicate that the composite beams exhibit high flexural strength, good flexural rigidity and desirable ductility under monotonic load. Based on the test results, the influence of some key design parameters (e.g., concrete top slab thickness, concrete bottom slab thickness, the existence of a concrete bottom floor and H-shaped steel sizes) on the flexural performance of the composite beams were also evaluated. It is worth highlighting that this new design leads to significant savings in structural material demands (such as shear connectors, steel reinforcement, and concrete), which in turn saves the resource and construction cost.