Design and behavior of welded T-stubs for DST connections

Conclusions from studies on the behavior of welded T-stubs subjected to tensile loading through the stem are presented, regarding the determination of limit states that control the behavior of welded T-stubs, and the evaluation of the applicability of current design recommendations to welded T-stub moment connections. A finite element model of a welded T-stub was created and subjected to monotonic tensile loads. The results of the analyses indicate that it is not always possible to make yielding of the T stern the controlling limit state because of the presence of the weld, and that allowing for a controlled prying of the T flange may be more appropriate. A series of one-half scale T-stubs were tested under monotonically increasing tensile loads. The experimental results show significant overstrength with respect to that predicted by current design recommendations and differences between the expected and actual failure modes. No weld failures were observed.