Comparative Numerical Analysis of Residual Stresses in Fillet and CJP Welded Built-Up Steel Box-Shaped Columns

Welded built-up steel box-shaped columns are widely used in building construction for their strength, stiffness, ease of fabrication, and installation advantages. However, the welding process for these columns may result in the accumulation of residual stresses, potentially impacting their structural stability and strength capacity. Given the limited literature on the residual stresses in the fillet and complete joint penetration (CJP) groove welded corner joints, it becomes imperative to explore the distribution and magnitude of these stresses in such columns. In this study, a sequential welding process was implemented to mimic procedures used in 3D printing simulations. This method treats each weld line individually while keeping adjacent lines inactive. A comparative numerical analysis was conducted to evaluate the residual stresses in two different corner weld joints of the columns. The shielded metal arc welding process is modeled in Abaqus software, with subroutine codes written in the Fortran programming language. The approach is validated by comparing it with experimental tests documented in the literature. Findings indicate that fillet welding results in lower residual stress levels in both the transverse and longitudinal directions compared with CJP groove welding. Moreover, the study finds that the through-thickness stresses in fillet and CJP groove welded columns are almost identical for the plate thickness considered.