Abstract

Steel shear tab connections are one of the most common types of connections used to connect steel beam to supporting columns and girders. Shear tab connections can be of two types: conventional shear tab (CST) and extended shear tab (EST). In EST connection, the shear tab is generally extended beyond the supporting member’s flange. While significant research has been conducted on conventional shear tab connections, research on extended shear tab connections is limited. First, this research presents the development of a three-dimensional (3D) finite element model (FEM) to study the behavior of shear tab connections, both conventional and extended shear tab, in W-Shape beam. Both material and geometric nonlinearities are considered in the FE model. The finite element model is validated against available experimental results on both conventional and extended shear tab connections. After validation of the FEM with experiments, a parametric study is carried out for W-shape beam with unstiffened CST and EST connections with supporting column web. In this parametric study, the effects of different parameters such as the number of bolts, length, and thickness of shear tabs on both CST and EST connections are studied.
Previously, some research has been conducted on the stability and strength of EST connections; however, to the best of this researcher’s knowledge, no research is currently available on the effect of extended shear tab connections on lateral torsional buckling (LTB) strength of the supported W-shape beam. The classic LTB equation in all codes is derived assuming both ends as simply supported. Since extended shear tab connections have extended tab lengths and have partial rotational rigidity, they do not act as perfect simple supports. Thus, EST connections can affect the LTB strength of supported beam. Also, the LTB behavior of I-beam for extended beam-to-column connections with multiple vertical rows of bolts has not been investigated to date. This research also presents a finite element (FE) analysis-based study to investigate the effect of extended shear tab connections on the LTB capacity of I-beam. The following parameters are considered in the study: shear tab thickness, bolt configurations with a single and double vertical line of bolts and different bolt numbers, beam unbraced length, bolt group centroid distance from the face of the supporting member, and the effect of stabilizer plate. Finally, a shear tab connection using a standard channel section, instead of the conventional shear tab, is examined in this research. It is observed that the proposed channel type shear tab connection can potentially be used in steel construction instead of the conventional or extended shear tab connections currently used, and the channel type shear tab connection can improve the LTB capacity of W-shape beam when compared to the currently used shear tab connections.