ABSTRACT
This study presents an inspection and rehabilitation work for a steel road bridge located in the section between Yoshida IC and Sagara-Makinohara IC, the Tomei Expressway. Opened to service in 1969, the bridge is a non-composite continuous steel girder bridge with 4 I-shaped girders. The traffic volume was at a high level up to 80,000 vehicles per day. Since the opening of a paralleled Shin-Tomei Expressway in April of 2012, the traffic volume was alleviated and decreased to 40,000. Because repainting for corrosion protection has not been carried out for 25 years, the paint was found deteriorated and some paint cracks became visible. Some paint cracks occurred at the locations of welded joints with a possibility causing fatigue cracks of the joints. Therefore, the pain cracks were inspected visually, whereas magnetic particle inspection was carried out to inspect the fatigue cracks. For the locations where fatigue cracks were found, repair was performed. After the repair, the girder was repainted for corrosion protection. The reason for the occurrence of paint cracks and the effect of repair and repainting are also discussed in this paper.
