Several cable-stayed bridges have shown signs of damages mostly induced by susceptibility of stay cables to2 wind-induced vibrations and corrosion. This has caused some concerns among bridge owners and initiated a series of inspection and health monitoring programs. This paper reviews existing methods for inspection and monitoring of cable-stayed bridges and summarizes the findings of several projects conducted to date. A unified approach for health monitoring and problem solving for stay cables of cable-stayed bridges is described. This approach has been developed based on information gathered from evaluation of the strength and reliability of stay-cable systems for nearly 30 long-span bridges worldwide and instrumentation, health monitoring, and inspection of more than 8 cable-stayed bridges. An ongoing project for inspection and damage detection of the Luling Bridge in Louisiana, an all-steel cable-stayed bridge, is described in detail. The approach follows the new unified methodology for addressing problems directed toward stay cables and their boundaries, and includes analysis, field measurements, and inspection procedures. Global and local damage detection methods have been used to complement each other, the former for rapid identification of damage and its location and the latter for in-depth inspection and potential damage detection of suspect locations. A summary of the findings is presented, and mitigation measures are recommended in this paper.
