2026 Volume 5 Issue 1 Pages 413-422
Takaoka City, Toyama Prefecture, manages approximately 1,160 bridges and is working to streamline its regular inspection procedures. There are 123 prestressed concrete deck bridges, including bridges dating back to the 1960s, the early period in prestressed concrete slab girder production. A rough assessment of load-bearing performance based on inspection results posed challenges, such as the lack of completed drawings, which left the internal structure unclear, and the extent to which cracks caused by ASR have affected load-bearing performance unclear. Therefore, in this study, the internal structure of a repre-sentative bridge was identified, laser measurements were taken from close range across the entire surface below the girders, and load tests were conducted. There was no correlation between the number of cracks caused by ASR and deflection in each bridge girder, and the results of the load tests were consistent with previous studies, which showed that the load-bearing performance of prestressed concrete beams does not decrease significantly within a certain range of expansion due to ASR.
