Rotation capacity of composite joints for slim‐floor beams

AbstractThe analysis of a composite beam‐to‐column structure requires knowledge about, on the one hand, the behaviour of beams and columns and, on the other, the joints between such elements. For beam‐to‐column joints, for example, the lack of appropriate design rules forces structural engineers to model joints as pinned, despite the fact that a certain joint rigidity and bending resistance is available because of the upper reinforced concrete slab. In this context, a research programme with experimental and numerical investigations was initiated at the University of Luxembourg [1]. This aim of this research was to identify the influence of two major joint components – the reinforced concrete slab and the steelwork connection – on the behaviour of composite joints under a hogging bending moment. Eight experimental tests were performed on beam‐to‐column joints. These tests were used to validate an FE model developed with the ABAQUS software, which allowed the simulation of further joint configurations without the need for additional laboratory tests.This article presents the results of experimental and numerical analyses. Good agreement was achieved between experimental tests and numerical simulations. The influence of the reinforcement and the steelwork connection on the structural properties of composite joints is derived and a new analytical method is proposed to determine the stiffnesses and rotation capacities of composite joints.