Longitudinal plate and through plate-to-hollow structural section welded connections

A longitudinal branch plate-to-rectangular hollow structural section (HSS) member connection tends to cause excessive distortion of the HSS connecting face. Such a connection therefore results in a relatively low, deformation limit state, design resistance. A "through" branch plate connection that extends through both walls of the rectangular HSS member can be used to increase the design resistance of a standard longitudinal branch plate connection. The results of an experimental test program and a corresponding numerical study, using the finite-element method on longitudinal and corresponding through branch plate-to-HSS connections are presented in this paper. The strength and behavior of longitudinal versus through branch plate-to-HSS connections is henceforth determined and a unified limit states design (LRFD) procedure for these cognate connections is proposed.