Myoko oohashi is a continuous PC box girder bridge which has been suffered from chloride attack by deicing salt. Because a part of main PC cables were found to be corroded, remaining structural performance was tried to be verified in this study. On site loading test guaranteed structural safety for the moment, however, the loading test did not provide the degree of deterioration. Then, FE analysis were conducted to know what happens with progression of corrosion. Numerical results revealed that loading test may catch only severe deterioration. Because numerical results implied that the progress of corrosion would make significant deformation, long term monitorinig was recommended and limit state was reset according to FE analysis.
