Welding residual stress release by a portable sheet-type ceramic heater was investigated for fatigue life improvement of welded parts between steel deck plates and trough ribs of highway bridge structures. A series of heat treatment experiment was carried out on test specimens modeling a steel plate deck with a trough rib. On the other hand, the experiment was simulated by a thermal elasto-plastic analysis considering creep properties for proposing an analysis model for simulation of heat treatment process. Based on the experimental and analytical results, the residual stress release effect for the welded parts between the deck plate and the trough rib by the portable heater was confirmed and an effective heating method was proposed.
