A comprehensive statewide underwater bridge inspection program was conducted for the state of mississippi. A total of 229 bridges onthe federal-aid system were inspected. An overview of the inspection program is presented. The average number of bents or piers inspected per bridge was four, excluding four long bridges that averaged 235 bents or piers each. The type of inspection equipment, inspection methodology, and evaluation process used are described. The inspections were conducted by two three-man commercial diving teams under the on-site direction of a professional engineer. Before the project, the divers were required to take a 1-week course on bridge inspections that included a field dive. The overall condition of the underwater portions of the bridges on the federal-aid system was good. Less than 10 bents or piers out of nearly 1, 900 inspected needed immediate attention. Only 6% were found to require remedial action over the next several years. Although a few scour problems were found, none were serious enough to immediately threaten the integrity of a bridge. To assist agencies in preparing for underwater bridge inspections, a method of rating six important aspects is given. This system would allow an agency to estimate the success of a proposed inspection process in terms of effectiveness as compared with cost. This paper appears in transportation research record no. 1268, Highway maintenance operations and research 1990.
Samenvatting