Emergency Evacuation Safety Research For Large Railway Stations Based On Auditory Perception

At present the railway stations in China have changed from the original single function into a comprehensive transportation hub with multiple functions such as traffic,leisure,shopping and dining,which brought a huge challenge in security protection field.The space has big traffic,passengers carrying a lot of luggage,large-scale population flow confined within the limited space.When emergency happen,combined with the harsh environment,such as fire and smoke cause the negative impact to crowd psychology,evacuation efficiency reduced,people panic may cause the secondary disasters,such as the stampede,even cause massive casualties.Therefore,the crowd of passenger security in railway station is an important subject to study.The aim of this paper is to study the passengers' characteristics,crowd noise and broadcast messages influence on evacuation process.Establish evacuation model based on authority guidance,and through the model to explore factors that influence evacuation efficiency,and provide the design basis for the passenger railway station building emergency evacuation.First stud y the basic theory of crowd evacuation,through the methods of literature review,field investigation,psychological behavior characteristics of railway station in the crowd were analyzed.By the impact of these phenomena to extract dynamic parameters whic h are related to voice including personnel density,velocity,flow of population,population composition and state that can affect evacuation efficiency,is studied theoretically.The basic modeling theory of mathematical calculation method,and the crowd evacuation has been discussed.Using field observation,questionnaire,videos,to research domestic and foreign large-scale railway stations.One typical large railway station is chosen as the site investigation,crowd characteristics,population flow,pop ulation speed and density of the passengers in the waiting area have been observed and statistic.Using subjective evaluation for emergency evacuation behavior and psychology,the fire protection knowledge and awareness,and the space acoustic environment.Gathering evacuation simulation data base,discuss the rule of crowd flow.The results of the questionnaire shows that crowd characteristics,the fire protection knowledge and awareness,the knowing of evacuation route and method,the way of receive broadcast,the acoustic environment would influence the determination and result of evacuation process.The crowd noise is inhibited factor and the broadcast is enhancing factor have been proposed.The crowd noise colourmaps have been built,proposed the changi ng rule of the sound field in different population distribution,and the simulation method for crowd noise.One typical railway station waiting hall has been measured acoustically,combined with the Odeon sound field computer simulation method for domestic six large railway station waiting area of the simulation results,and the Simulex crowd evacuation simulation software real-time forecast of population distribution in the process of evacuation,to study the crowd noise's masking to broadcast message.First proposedr railway station broadcasting definition within the two important indexes of direct sound(SPL)and speech intelligibility(STI),proposed the sound pressure level with the distance decay curve and the sound transmission rule in waiting area.Combined the noise map in different time based on the crowd forecast distribution diagram,proposed the real time simulation method of crowd noise.Voice is a promoting factor of evacuation process,so based on the cellular automaton model,an auditory perception cellular automaton model has been built."Static information"(structure,blockage,etc.)and "dynamic information"(broadcast information,etc.)is obtained as key factors in evacuation process,using simulation and experiment method for deeply studied.Using auditory perception cellular automaton model,setting different conditions under public safety emergency,to simulate the emergency evacuation process in different location and scene.Respectively are evacuation simulation under fire circumstance,different crowd characters,different exit using efficiency and alarm system turned on.Discuss the evacuation process after emergency with setting different conditions influence for evacuation time and evacuees' number.The design suggestion has been proposed.