Post-earthquake Fire Risk Assessment And Fire Spread Modeling In Urban Area

Post-earthquake fire is the most dangerous secondary disaster following earthquake, which can cause severe losses. Comprehensive and effective risk assessment of post-earthquake fire is the necessary avenue which recovery and lighten huge damage of post-earthquake fire. In this paper, urban area is taken as the research object and post-earthquake fire risk assessment in urban area is taken as the research content, a model of post-earthquake fire risk assessment in urban area is established. First, index system of risk assessment of post-earthquake fire is established, and the index weight is accomplished by using Analytical Hierarchy Process (AHP). Risk classification of the urban area post-earthquake fire is put forward by grading factors that affect fire risk. The assessment result will be use for the high hazard area determination of post-earthquake fire in urban and instruct plan of urban anti-shake and the disaster prevention.Based on the urban community fire spread model using cellular automata by A.Ohgai, considering the effect of the building's destruction by earthquake and the difference of different burning neighbor on fire spread, the fire spread model is improved. Analyzing the effect of building in risk classification area, building structure, the destruction of the buildings and wind velocity and direction on fire spread, a CA model of post-earthquake fire spread in urban area is established. Using matlab language, the effect of local environment improvement, wind speed and direction, spot fire or new fire origin, different risk classification, different earthquake's intensity and urban hazards on fire spread have been simulated. The model presented in this paper can simulate the process of urban fire spread quickly. The reproduction of fire process not only improves people's cognition, but also provides the guide for urban planning.