Abstract
Measuring the stress and checking the welded sections are carried out as the investigation of the fatigue cracks at the frame connections of steel bridge piers. The measured stress was found to be much larger than that of considered in the design. Also, large lack of fusion was found in the double bevel groove type welded sections. Because of these large stress and defeats, the fatigue cracks were developed. As the temporally-repair, bolted splice plates were installed on the box webs of the connections. This repairing decreased the measured stress by about 50%, so that these piers can be used safely temporally. But still, it is needed to remove all the fatigue cracks as the final repair. Further studies on the method of this removing are necessary.
