Numerical Analysis of Endplate Beam-to-Column Joints under Bending and Axial Force

Abstract

Steel beam-to-column joints are often subjected to a combination of bending and axial forces. Alternatively, significant axial forces can also be present at the joint in cases like: pitched-roof portal frames, sway frames or frames with partially constructed floors. Despite this fact, only very simplified design procedures are available for the analysis and design of beam-to-column joints under these actions. A single empirical limitation to the applied axial force of 5% of the beam plastic resistance under axial force is the only enforced provision present in the Eurocode 3 (1). The main purpose of the present paper is to describe a numerical investigation developed to fully characterize the structural response of endplate beam-to-column joints subjected to bending and axial forces. Experimental results, carried out at the University of Coimbra, Portugal, were used to calibrate the finite element model. These analyses were focused on expanding the test results and enabling a complete understanding of the structural behaviour of this particular type of semi-rigid connections.