Optimization Of Fire Evacuation Routes In Large Commercial Premises

With the rapid development of China's social economy,various large-scale commercial buildings are very popular in the city.These commercial buildings have the characteristics of large area,large volume and large space span.These large-scale commercial buildings have brought some difficulties for evacuation.Although our country's code specifies the setting of evacuation indication sign,the width and distance of evacuation exit,whilst the specific requirements of building evacuation path are still not clear enough.The evacuation indication sign only points to safety exit,but lacking of effective planning,therefore resulting in low evacuation efficiency.Thus,the purpose of this paper is to optimize the evacuation path of large commercial buildings,and to further improve the efficiency of evacuation for future architectural designers to provide reference,which has a certain practical significance.Firstly,based on the shortest evacuation path algorithm of Dijkstra algorithm,the specific methods of each shortest evacuation path are determined by digitizing the evacuation path map.Secondly,based on the method of determining the shortest evacuation path,the direction of evacuation is determined by the weighted method,without direction and the boundary points are introduced into the partial evacuation path to get the evacuation direction for each evacuation path.Thirdly,the shortest evacuation path and the direction of evacuation are applied to the CAD plan with Visual LISP software on the AutoCAD platform,and the optimization method of the evacuation path on the CAD platform is realized.Finally,building EXODUS software is adopted to simulate the evacuation of a department store and verify the feasibility and rationality of the evacuation path optimization method.The number of evacuation was determined with the black box theory model,and three evacuation scenarios were considered: no evacuation indication scenario 1,actual evacuation indication scenario 2 and optimized evacuation indication scenario 3.The evacuation time before and after the optimization of evacuation path was compared and analyzed.According to the evacuation results,the evacuation efficiency of the optimized evacuation path scenario 3 is obviously improved because of the shorter evacuation distance,the higher utilization rate of the safety exits,and the shorter time to find the route.Compared with the scene without evacuation path,the evacuation efficiency is improved by 32.5% with 47.7 seconds shorted time,and 27.7 seconds with 15.4% respectively.Finally,the feasibility and rationality of the evacuation path optimization method are verified.