Non-destructive testing methods in the U.S. for bridge inspection and maintenance

This paper presents an overview of how Non-Destructive Testing (NDT) methods are currently impacting bridge management in the United States (U.S.). It is necessary for researchers and policy makers to have a clear understanding of how NDT methods are being utilized if they are to improve bridge management strategies. After a historical review of the development of a bridge management system, a detailed discussion of currently available NDT methods illustrates the principles, application areas, and limitations of the methods. As state Departments of Transportation (DOTs) are the key bridge management institution in the U.S., the authors conducted a thorough review of current state DOT bridge inspection manuals to identify how NDT methods are incorporated into state bridge management systems to reflect their own local conditions and in what situations they are considered. The authors found that total 30 states have their own bridge inspection manuals, among which eight states addressed the use of NDT methods in their inspection manuals explicitly. Only one state DOT, Indiana, discussed NDT methods and their applications in detail in a separate section.