In order to investigate the fatigue performance of corroded RC T-shaped girder bridges early built in China,10 RC T-shaped girder specimens with actual corrosion rates ranging from 4.12%to 13.72%were fabricated,and fa-tigue tests with stress ratios ranging from 0.25 to 0.67 were carried out.The experimental results are as follows.The deflection,bending crack width,and material strain of the lightly corroded specimens exhibit a clear ＂three-stage de-velopment＂characteristic of rapid development in the early stage,stable changes in the middle stage,and rapid growth in the later stage,and its fatigue failure is generally marked by exceeding the limit of bending cracks.When the mod-erately/severely corroded specimens are subjected to fatigue loads with a stress ratio of less than 0.30,the stable de-velopment stage in the middle stage basically disappears,and the latter may even experience low cycle fatigue failure.When the stress ratio does not exceed 0.31,the fatigue life of the moderately/severely corroded specimens is reduced by about 48%and 71%respectively compared to the lightly corroded specimens.When the stress ratio decreased from 0.66 to 0.31,the fatigue life of the moderately/severely corroded specimens decreased by about 85%and 90%,re-spectively.Due to the actual fatigue life of the moderately/severely corroded highway RC T-shaped girders is much lower than the design fatigue life of 2 million times,measures should be taken in the phase of design and maintenance to reduce the corrosion rate of longitudinal bars and fatigue stress amplitude.
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