Research On Fire Evacuation Of University Libraries Based On BIM Technology

With the increasing desire for learning and continuous investment in education in China,more and more people choose libraries as their main place to acquire knowledge.Libraries store a large number of paper-based collections,materials,wooden tables and chairs,and electronic devices,among others.Once a fire occurs,it can cause serious damages to the building and the items stored inside,as well as pose a threat to the health and safety of the occupants.Therefore,it is of great importance to conduct in-depth research on the factors such as the combustion mechanism of fires,personnel evacuation,building information modelling,fire numerical simulation,indoor route planning,risk assessment,and other related issues in university library buildings.By studying and developing fire prevention and response measures,it is possible to effectively prevent the occurrence of fire accidents.Firstly,to address the issue of the "physical information isolation" in fire safety,using a university library as a case study to explore the combustion mechanism and development process of library fires,as well as the characteristics of these fires.Through simulation experiments and numerical modeling,this study investigates the entire process of fire spread,smoke diffusion,and personnel evacuation in the library.By combining Building Information Modeling(BIM)technology with fire spread,smoke diffusion and personnel evacuation planning simulations,this study conducts further research through numerical modeling and visualization analysis.It presents a reasonable configuration of escape routes utilization rate to reduce the probability of congestion and enhance the modernized emergency management capability of the library.Secondly,to study the rules of indoor fire spread and the impact of smoke on personnel evacuation in a more sophisticated manner,this paper uses the computer software "BIM+Pyrosim/Pathfinder" as the core to establish simulation models of fire scenarios and personnel evacuation analysis models in the library.In the fire simulation scenario,a quantitative analysis method is used to evaluate the impact of safety indicators(such as fire temperature,CO concentration,and visibility)in the simulation model on personnel,to determine the range of personnel that it can accommodate,and to improve the scientific and rationality of personnel evacuation plans.In addition,to improve the efficiency of personnel evacuation in the library,this paper applies a personnel evacuation simulation model to visualize the evacuation behavior and queue congestion of indoor personnel.After comparative analysis of the utilization rate of various safety exits,a method of personnel diversion and correction of evacuation behavior is proposed to formulate a personnel evacuation plan and improve the overall evacuation efficiency.The simulation results show that by using this method to plan evacuation plans,the safety evacuation time has increased by 226 s.The simulation experiment of "BIM+Pyrosim/Pathfinder" verifies the application value of combining BIM technology with emergency safety management,and provides scientific support and data support for on-site emergency command and decision-making in case of fire.Finally,by optimizing the algorithm,we aim to improve the efficiency of the path planning model and the accuracy of the risk assessment model.On the one hand,a path planning model is established with "BIM+Pyrosim+MATLAB" as the core,which aims to solve the space complexity problem of traditional A* algorithm and artificial potential field algorithm,and improve the efficiency of global path planning in static environment.Besides,the dynamic information of smoke diffusion is integrated into the path planning model to improve the accuracy and smoothness of evacuation path planning for both dynamic and static obstacles.A new hybrid path planning model is constructed by combining improved A*algorithm and artificial potential field algorithm.Simulation results show that the hybrid path planning model outperforms the single model with fewer traversed nodes and better path smoothness.On the other hand,an emergency evacuation risk assessment model is built with "BIM+Pathfinder+MATLAB" as the core,which combines the improved Extreme Learning Machine(ELM)and the improved Improve Seagull Optimization Algorithm(ISOA)to enhance the model’s solving ability and generalization performance.The simulation results indicate that the emergency evacuation risk assessment model achieves an accuracy rate exceeding 92%,which outperforms commonly used models such as DNN,CNN,and ELM,demonstrating a high level of accuracy.In summary,based on BIM technology,this study conducted simulation analysis on three aspects of fire simulation model,personnel evacuation model,indoor path planning model,and evacuation risk assessment,using digital and intelligent research methods to improve the fire safety level of the library,enhance the performance of fire personnel evacuation,and ensure the safety of indoor personnel.