The subject of this research was a concrete T-girder bridge which had been exposed for 40 years to the sub-tropical archipelago environment off the east coast of Okinawa, with large amounts of windblown salt, high temperatures and high humidity, a harsh environment for salt damage and steel corrosion. It had suffered damage in the forms of 1) concrete spalling due to reinforcing bar corrosion, 2) internal loss of cross section and severance in internal reinforcing bars, and was therefore removed. Various tests and inspections were applied to analyze the state of deterioration of a real salt-damaged bridge, with the aim of providing technical reference material of use in formulating appropriate maintenance management methods. Distant visual inspection was performed prior to removal of the girder. After the removal, close visual inspection and non-distractive inspections were performed. Compressive strength, elastic modulus and chloride ion content of the concrete were measured. Corrosion of reinforcing bar was observed after chipping the concrete. Chloride-induced deterioration inside the concrete and competence of non-destructive inspection for the deterioration were studied. Static loading test and fatigue-test were performed.
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