Research of Punching Performance of Reinforced SFRLAC Superposed Two-Way Slabs

Abstract

This paper introduces the test results of eight steel fiber reinforced lightweight aggregate concrete (SFRLAC) superposed two-way slabs under punching load. The tensile and compressive zones of the slabs were cast with the SFRLAC and the ordinary concrete respectively. The slab was simply supported along the four edges under central concentrated load on the short column. The main parameter of SFRLAC was the fraction of steel fiber by volume of 0.8%, 1.2% and 1.6%. The measurements were made such as the deflection, the strains of steel bar and concrete, the crack distribution, the loads corresponding to the yielding of steel bar and the ultimate state. It proved that the punching resistance of SFRLAC superposed two-way slab increased about 51%~78% with the increasing fraction of steel fiber by volume, the ability to resist punching deformation was enhanced remarkably, many fine cracks distributed on the tensile surface, and the ductility at failure state increased to a certain degree.