Inspection and Maintenance of Bridge Stay Cable Systems
cable stayed bridges, stay cables, NDT, inspection, vibrations, corrosion
In this synthesis effort, a worldwide search of information on inspection, repair, testing, and design of stay cable, was undertaken. On-line sources of information as well as engineering databases were examined. Contacts were made with a number of knowledgeable individuals for information. A questionnaire was prepared and distributed to all state and provincial departments of transportation in the United States and Canada. Completed questionnaires were received from 75% (27 of 36) of all known U.S. cable-stayed bridges and 81% (13 of 16) known cable-stayed bridges in Canada. Based on this information, various methods, approaches, and practices are explained in detail and their strengths and weaknesses identified. Specific approaches to inspection and repair are presented and discussed. Challenges in the inspection and maintenance of cable-stayed bridges are significant. The main tension elements (MTEs) within a cable bundle are, in most cases, hidden from the view of inspectors. Access to cables for visual inspections or nondestructive testing is generally dif- ficult and, in the case of the anchorage zones, nearly impossible. Those who are responsible for the inspection and maintenance of stay cables are faced with challenges for which proven and accepted methodologies and tools are limited and, in many cases, very costly. There are 36 cable-stayed bridges in the United States and 16 such bridges in Canada. As of 2005, the average age of cable-stayed bridges in the United States was 11.4 years. As these bridges age, the need for effective inspection and maintenance methods and tools becomes more acute.
Tabatabai, H., “Inspection and Maintenance of Bridge Stay Cable Systems,” NCHRP Synthesis 353, National Cooperative Research Program, Transportation Research Board, 2005, 75 pp.