FE analysis of LTT elongated bead method for boxing welded joints with various thicknesses

The fatigue experiment of LTT elongated bead overlaid on a boxing fillet joint, with the thickness of 20mm for the main plate and 16 mm for the stiffener, showed that the fatigue life can be greatly extended without crack occurrence at the weld toe and crack propagation from weld root. To apply the LTT elongated bead method to most of boxing fillet welded joints with various thickness combinations of the main plate and stiffener, numerical experiments were conducted. Through comparing the stress concentration, residual stress and stress intensity factor in various sizes of boxing fillet joints with those in the specimen for fatigue tests, the fatigue safety was evaluated. It can be evaluated that the LTT elongated bead method can be applied to the boxing fillet welded joints with the plate thickness from 6.0 mm to 30 mm.