Fatigue Strength of Fillet-Welded Transverse Stiffeners with Undercuts

Presently, wrapping of the welds at the ends of stiffeners is not done to avoid the undercutting of the stiffener corners and the attendant weld repair. The fatigue performance of stiffeners with undercuts was evaluated in a factorial design fatigue experiment. Undercuts at the flange edge and filling of the stiffener cope with the fillet weld were also evaluated. The undercuts did not influence the fatigue performance of the stiffener weld even when very large undercuts were purposely introduced. Filling of the cope with a continuous weld and flange undercuts also did not change the fatigue performance of the connection. Wrapping of welds in locations were corrosion at the stiffener to plate interface may occur should be allowed. The undercuts in the stiffener that may result are not of any consequence and may be left in place. Covering the stiffener cope by continuing the fillet weld is an alternate method of sealing the weld. 17.