Investigation of weld root fatigue of single-sided welded T-joints
International Conference on Marine Structures, MARSTRUCT: 309-316 (2015-03)
Contribution to Conference
Several welded joints in ship and offshore structures can be performed only from one side, e.g. tubular connections in offshore structures. Full penetration is usually aimed at, but sometimes partial penetration occurs, either unintended or intended in order to reduce the welding effort. Such welds are assessed with the lowest fatigue class in the nominal stress approach. However, weld root failures are rarely known although fabrication is frequently performed under unfavorable conditions regarding welding position and gap width. Therefore, fatigue tests were performed with T-joints subjected to bending to investigate weld root fatigue and possibly optimize the welds. 25 mm thick plates were joined with singlesided welds having full and partial penetration (HV and HY-welds), partly performed without and with gap. The results are assessed using the nominal, structural hot-spot and effective notch stress approaches with the aim to rationally consider the actual weld throat thickness of partial penetration welds.