Applicability of welding for repair/reinforcement of overage bridges

摘要

The obtained results are as follows.rn(1) Steels manufactured in around 1930 contained more sulfur and phosphorus comparing with contemporary steels contain.rnWelded by using a general filler wire:rn(2) No defects or cracks occurred without dealing with special treatment like as pre- and/or post-heating.rn(3) It was found that the welded joints with steels used for a long term had enough mechanical properties.rn(4) It was reconfirmed from the results of fatigue test that no defects or cracks occurred without dealing with special treatment like as pre- and/or post-heating.rn(5) Charpy absorbed energy (_V E) was the smallest in the base metal. It was elucidated that brittle fracture percentage of the base metal was extremely high comparing with that of SM400A.rnEven if welding was used for joining in repair and reinforcement on the existing old steel bridges, there were no problems in the welded joints. It was rather necessary that the base metal should be much noted.