Abstract:Little attention is usually paid to the fire safety problem of bridge structures in the plan and design stage. This paper established a complete bridge fire risk assessment system to realize the assessment and prediction of the potential bridge fire risk in the plan and design stage. First, a multilayer risk evaluation index system of bridge fire safety was proposed by risk identification process based on performance based and fire scenario analysis. Then by innovatively introducing fuzzy mathematics into the analytic hierarchy process, the AHP FCE method was presented for evaluating the risk probability and risk loss, integrating the advantages of traditional quantitative evaluation method and qualitative evaluation method. The weighting coefficients of the indexes were calculated using the analytic hierarchy process (AHP) while the fuzzy comprehensive evaluation (FCE) was used to realize the multilayer comprehensive evaluation. Finally, the risk level of bridge fire safety was obtained by using the 2 dimension evaluation model based on the computed values of risk probability and risk loss and the evaluation criteria; and the basic risk control principles were given. As an example of engineering application, the fire risk level of a partially cable stayed bridge was assessed by using the proposed fire risk assessment system.
