Behavior analysis of bar gaps in welded YT-joints for rolled-steel circular hollow sections.

Abstract

We present a parametric analysis of gap variation between the lap brace and through brace of YT welded joints for rolled-steel circular hollow sections on plane steel structures. Our aim is to investigate the collapse behavior of YT-joints under lap brace axial compression. In particular, we focus on e/d0 ratios above 0.25 so bending moments can be taken into account during the design. We find that joint failure is primarily due to chord wall plastification (Mode A) and cross-sectional chord buckling (Mode F) in the region underneath the lap brace. Our joint design followed the Limit States Method, and our results were based on a comparative analysis of three different methods: an analytical solution derived from a set of international technical norms, an experimental analysis, and numerical modeling using Ansys as calibrated by our experimental results.