3D simulation of bolted connections to unstiffened columns—I. T-stub connections

Abstract The paper presents a finite element methodology in a three-dimensional (3D) framework to study numerically the stiffness and strength of the T-stub to unstiffened column flange bolted connection as part of a comprehensive research program to investigate the behavior of endplate bolted connections. In such connections, the axes of rotation of the T-stem and column flange are at right angles; the planes containing the tensile forces are also perpendicular to each other. Therefore, they are highly interactive spatially. The main objective here is to study the applicability of the model to such a connection, so that most of the important features which are not accessible to routine experiments, like prying action and gradual plasticity of components, can be monitored. ANSYS, version 4.4, a large-scale general purpose finite element code is selected for this analysis. Initially, the simplest connection with the bolt groups in tension, which is a symmetric T-stub hanger with a single line of bolts parallel on each side of the web, is considered. Then the T-stub connection to an unstiffened column flange is discussed. Analytical results of a full-scale extended endplate connected to unstiffened column flange will be presented in Part II, a companion paper (Journal of Constructional Steel Research, 1996, 40 , 189–223) in which the structural properties of such connections will be discussed.