Plastic Behavior of Shear Tabs Welded to Flexible Wall Support

Abstract

This paper presents an experimental study of six steel shear tab connections to hollow structural section columns. This study focuses on the plastic behavior of shear tabs and their supporting column walls. The column walls had width-to-thickness ratios ranging from 21 to 34. Large bending deformations were observed on both the column walls and the shear tabs. All six specimens failed owing to an excessive vertical deflection followed by a punching fracture of the tube wall around the perimeter of weld at the top of tab. The test results were found to agree well with two plastic mechanisms proposed for analysis. This study demonstrates that the shear strength of the tabs welded to a flexible wall support should be reduced when compared with that of the tabs welded to a rigid support. This paper also finds that the width-to-thickness ratio criterion for a rigid wall support is a function of the ratio of the length of tab to the width of the supporting wall and the relative bending strength between the tab and the wall.