Influence of Weld Penetration Depth on Fatigue Behavior of Beam-to-column Connections in Steel Piers
Shigenobu KAINUMA, Naofumi HOSOMI, In-Tae KIM
The purpose of this research is to investigate the influence of the weld penetration depth on the fatigue behavior of beam-to-column connections in steel piers. Fatigue loading tests were carried out on three types of the welded connections. FEM analyses were also performed on the specimens to clarify the stress distributions at the vicinity of the connection. The observation of fracture surfaces indicates that fatigue cracks are initiated not from the inherent cavity at the end of the connections but the weld roots and/or weld toes. The fatigue cracks may be initiated at the weld roots and toes when the weld penetration depth is less than one-third of the flange plate thickness. The S-N diagrams based on hot-spot stress range, of which extrapolation points are O.5t and 1.0t (t: flange plate thickness), shows that the fatigue strength is almost the same despite the weld penetration depth.