Fire Risk Evaluation of Cable Bridges due to Vehicle Fires

Abstract

<p>Cable bridges use multiple cables as main members, and there is a risk of bridge failure in the event of cable loss. To manage the bridge safety from such event, a risk analysis method is necessary. In this study, fire risk analysis was performed on Seohae Bridge, a steel composite cable-stayed bridge, and on Yi Sun-sin Bridge, the longest suspension bridge in Korea. A fire risk analysis method is proposed to determine the final annual frequency of bridge failure. This method calculates the annual frequency of vehicle fires based on statistical data and appropriate assumptions, and determines the conditional probability of exceeding the limit state of the main structural member through fire analysis and bridge structural review. For the statistical data on the annual fire frequency, domestic statistical data were investigated and actual data were analysed and applied, and various probabilities such as oil leakage and ignition probability in the event of an accident were assumed.</p>