Experimental Study on Flexural Behavior of the Composite Bottom Slab of the Stiffened Steel Truss

Abstract

In order to study the influence of rib size on the flexural performance of the new reinforced truss concrete composite floor slab, two precast reinforced concrete floor slabs and one ordinary reinforced truss composite floor slab were designed and manufactured for flexural performance tests. The failure mode of the concrete slab under uniform load was analyzed, and the influence of rib size on the flexural capacity of the floor slab was studied. The results show that the stiffening of the steel truss composite slab can significantly improve the stiffness of the precast slab and effectively solve the problem of excessive deflection of the precast slab during construction. On the basis of the experimental study, the influence of the top chord steel bar diameter, concrete rib height and rib width on the short-term stiffness of the floor is deeply analyzed by using the finite element refined modeling. The results show that the diameter of the top chord reinforcement and the width of the concrete rib are positively related to the stiffness of the composite slab, and the height of the concrete rib has little effect on the initial stiffness of the precast slab, which mainly plays a role in the later stage.