The Effect of Steel Trusses on the Mechanical Performance of Laminated Precast Slabs

Abstract

Laminated concrete slabs can deliver desirable structural properties and effectively improve the speed of construction. According to their basic specifications, laminated concrete slabs comprise a 60 mm precast concrete slab and a 70 mm concrete layer cast in situ, with a steel truss bar at a height of 80 mm. This paper studies the effects of the steel truss bar on the mechanical properties of precast slabs. A simple but accurate method is proposed for calculating the stiffness of precast slabs. The test results show that the steel truss bar has a limited effect on the stiffness of the precast slab but will weaken the compression strength of the concrete, resulting in a significant reduction in the ultimate bearing capacity of the precast slab. Further discussions show that eliminating the steel truss bar and appropriately increasing the thickness of the precast slab can effectively increase the stiffness and load-bearing capacity of the precast slab, as well as reduce the consumption of the floor reinforcement by about 26%.