Study On Risk Assessment Method And Index System Of Office Building Fire Accident

In recent years,with the rapid development of urbanization in our country,the influx of personnel into the city has led to the densely populated city.At the same time,with the application of high technology,large volume and high-density building characteristics become the main form of urban planning,which causes the number of fire incidents to rise year by year,and major fire accidents occur frequently.The occurrence of fire accidents seriously harms people’s economic property and life safety.How to do a good job in building fire prevention measures at the stage of building design has become the primary issue of architectural design.The occurrence of fire has certain contingency and complexity.It is the result of cooperation of various factors,but it also has its regularity.The rule of fire spread can be summed up.Studying the law of fire spread can provide improvement plan and preventive measures for the fire protection design in the architectural design stage,which is of great significance for maintaining social stability and sustainable development,human life and property safety,energy saving and environmental protection.Taking the performance-based fire protection design as the research background,through the fire numerical simulation and evacuation simulation,combined with the theoretical research method of accident tree analytic hierarchy process(AHP),a preliminary study on the risk assessment index system of a certain office building fire accident is carried out.(1)First of all,starting from two aspects of the spread of fire and the influencing factors of personnel evacuation,we collate the relevant research results at home and abroad,study the basic mathematical models of fire spread and evacuation simulation,and consider the scope of application of FDS based on the large eddy simulation method and the classical social force model.(2)Through the collation of the relevant data and the reasonable simplification and assumption of the fire scene,taking a certain office building as an example,8 fire numerical models and 3 individual evacuation models were established by using Pyrosim fire numerical simulation software and Pathfinder evacuation software.The smoke spread in the office building and the change of harmful gas produced by the smoke are used to monitor the temperature changes in the fire spreading process,the harmful gases(mainly CO)in the smoke and the visibility of the smoke;analyze the problems existing in the evacuation process,influence the factors of evacuation,and make a preliminary judgement on the fire protection design and the safe evacuation ability of the office building.(3)Through the fire numerical simulation and evacuation simulation of the office building,the 3D animation demonstration process of the built-in software Smokeview of the FDS numerical simulation software is observed.The factors that affect the development of fire and the evacuation of personnel are summarized,combined with the structural attributes of the office building.With the expansion of fires,two intermediate events,which cause significant economic property losses and casualties caused by evacuation,are deductive reasoning.A fault tree model of office buildings is established by accident tree method.The structural importance of each fire influence factor in fire accidents is obtained through the minimum cut set algorithm of fault tree model,and each factor is summarized.(4)Finally,by summarizing the structural importance of each fire affecting factor in fire accidents,the risk assessment index system of office building fire accidents is established,and the weight of each factor in fire is obtained by AHP,and reasonable suggestions and effective prevention and control measures for building fire protection design are put forward.