针对日益严重的桥梁火灾问题，采用模糊综合评价的方法对车致桥梁火灾发生概率进行研究． 首先，全面考虑车辆火灾发生概率的各影响因素，建立车致桥梁火灾风险评价指标体系． 然后，采用层次分析和熵权相结合的方法确定各指标权重，并采用灰色模糊理论对初始评价矩阵进行处理，从而建立了车致桥梁火灾发生概率评价模型． 由于桥梁火灾与隧道火灾具有很大的相似性，参考隧道火灾统计数据，建立了车致桥梁火灾频率评价标准． 最后，对某桥梁进行应用实例分析，得到了货车火灾发生的概率． 研究结果表明，车致桥梁火灾发生概率模型适用可行，可为桥梁抗火设计和安全维护提供决策依据．

In view of the fact that bridge fires have posed an increasingly serious problem，the fuzzy comprehensive evaluation method is adopted to analyze the occurrence probability of vehicle fires in bridges in this paper． First，the risk evaluation index system of bridge fires is set up by taking into account all kinds of factors influencing the occurrence probability of vehicle fires． Then，the weight of each index is determined by combining the analytic hierarchy process (AHP) and the entropy weight，and the initial evaluation matrixes are also processed based on the gray fuzzy theory． Thus，an occurrence probability model of bridge fires is constructed． Because of the great similarity between bridge fires and tunnel fires，a frequency classification criterion of vehicle fires in bridges is set up by collecting the data of tunnel fires as the reference． Finally，the case analysis of a bridge is carried out，and the occurrence probability of a truck fire is obtained． The results show that the proposed model is feasible and applicable，so it can provide the decision-making basis for the fire-resistance design and safety maintenance of bridges．