Analysis of road tunnel fire risk based on Fuzzy Fault Tree method

On the basis of system safety engineering theory and fire science, a model of tunnel fire named Fuzzy Fault Tree Analysis (FFTA) Model has been built according to the uncertainty of tunnel fire and the subjectivity of traditional fire risk analysis method. Using triangular fuzzy theory, the fuzzy probabilities of basic events and top events based on experts cognition level. Then the relationship degrees of influence factors was compared by their fuzzy classifications. The result shows that fire sources and fuels are the main causes of tunnel fires, and the failure of fire extinguishing equipments is in the second place. In order to reduce the risk of tunnel fire, the factors of tunnel fire and their logical relationships should be analyzed comprehensively, the possibility of tunnel fire should be monitored dynamically, and fire protection strategies should be established, which is significant to the safe operation and sustainable development of transportation.