Abstract |
The report presents a statistical summary of the cause and cost of bridge failures based only on a review of damage reports in the FHWA Emergency Relief files for major floods that have occurred during the last few years. As was anticipated, these reports yielded very limited reliable data, so the dollar projections must be viewed accordingly. The general trends, however, should serve as guideline for future research in related areas. Of 383 cases, 14.9 percent reported damages to the superstructure, 24.5 percent to the pier, and 71.8 percent to the abutment; in 43.2 percent of the cases, the damage extended to the approach roads. In 341 cases where the causes of failure were either stated in the original files or theorized by the reporter, only 6.9 percent of the failures were attributed to riverbed changes (aggradation and degradation), 29.6 percent were attributed to vigorous change in flow, 38.8 percent to flowpath deficiency, 20 percent to floating debris, and only 4.7 percent to structural deficiency. (Modified author abstract) |