補修溶接を施した既設クレーンランウエイガーダーの超音波衝撃処理による疲労寿命向上
2007 年 14 巻 55 号 p. 47-58
詳細
2007 年 14 巻 55 号 p. 47-58
A fatigue improvement method using ultrasonic impact treatment, which improves both toe profile and residual stress condition, was examined. This method is applied to in-plane-gusset detail and out-of-plane gusset detail of existing crane runway girders. Comparison with conventional grinding method was conducted by small joint specimen fatigue tests, and UIT gave much better result. Also, its applicability to mild steel and influence from repair weld is examined through girder fatigue tests. Significant fatigue improvement was obtained for 400MPa class mild steel. Also, the effect is not reduced by repair weld. This result has encouraged the proper application of UIT for existing CRGs.
