Research On Performance-based Fire Safety Design For Large Space Commercial Buildings

With the rapid development of economy and the effect of urban population settlement,large space commercial buildings emerge as the times require and are gradually favored by consumers.Large space commercial buildings with large volume,large span,irregular internal space and various commercial forms make it difficult to design fire safety.The following problems often occur,such as: the area of fire prevention zone is too large,the safe evacuation distance exceeds the standard,the automatic alarm system and the automatic sprinkler fire extinguishing system can not work properly and perfectly.In China,there is no specific code for this kind of building.The performance design method based on the principle of fire engineering has made up for this deficiency.The performance-based design method is based on the criterion of specific performance,combined with the computer fire simulation and evacuation simulation technology,which can be used to design the large space commercial buildings in accordance with their own characteristics.In recent years,Beijing New Poly Building,Dalian Integrated Commercial City and other large-space commercial complex has been used this method.This paper first analyzes the fire causes and fire characteristics of large space commercial buildings,then analyzes the factors affecting the safety evacuation of people,and carries out a questionnaire survey on the consumers in Shijiazhuang Wanda Square.This questionnaire survey analyzes the psychological and behavioral characteristics of the special group of urban consumers in the face of fire.Finally,the methods and steps of performance-based fire prevention design are described,and three fire scenarios are set up for a commercialcomplex on the basis of possible fire source points.Each fire scene was simulated by FDS,and the relevant parameters of smoke were analyzed.Due to the fact that the density of people in shopping malls during holidays is significantly higher than that of working days,the Pathfinder evacuation simulation is done for the holidays and working days respectively under the same fire scene.This paper analyzes whether the Available Safe Egress Time of evacuation in each fire scenario is larger than the Required Safe Egress Time,and puts forward some feasible optimization suggestions for the simulation results.In holidays and working days,the evacuation characteristics of different personnel density are compared in order to study the influence of personnel density on safe evacuation.