Partial joint penetration plus welds for tubular joints: Fabrication and SCFs

Abstract

This paper proposes a new set of convenient welding details, namely, the partial joint penetration (PJP) plus, that ensure simple but high quality controls for tubular connections widely used in onshore and offshore structures. The PJP plus welds reduce significantly the requirement on workmanship compared to the three major connection details available for tubular structures: the complete joint penetration (CJP) welds adopted in offshore jacket frames, the cast nodes used in tubular bridges and single-sided welds with a backing plate fabricated for tubular bridges. This paper describes the fabrication procedure of the PJP plus weld details for typical circular hollow section joints. The numerical investigation compares the stress concentration factors (SCFs) near the weld toes of the brace-to-chord intersection for both PJP plus and CJP welds. The maximum SCF values near the hotspot locations indicate that the PJP plus welds do not significantly degrade the fatigue life of the welded connection compared to the CJP welds if the same S-N curve is used for both weld details.