Weld design for hollow structural section connections: application to Canadian Standards

This article presents a comprehensive review of existing North American research on weld effective lengths for hollow structural section (HSS) connections. Data from 393 experiments and finite-element analyses is analyzed to determine the inherent reliability index (β⁺) of existing and proposed AISC 360 formulae for weld effective properties in axially loaded rectangular hollow section (RHS) T-, Y- and X-connections, RHS gapped and overlapped K-connections, RHS moment-loaded T-connections, and circular hollow section T-, Y- and X-connections, when used in conjunction with CSA S16-19 Clause 13.13.4.3(a) for design of welds to the ends of HSS branches. Modifications to the formulae are proposed to achieve β⁺≥ 4.0 (the target reliability index for connectors according to Annex B.4 of CSA S16-19), and recommendations are made to facilitate a “fit-for-purpose” design approach for welds to HSS. These are proposed for the next scheduled revision of CSA W59.