| In recent years,with the continuous development of population aging all over the world,there are more and more buildings for the elderly with low fire safety,and the demand for safe evacuation of the elderly is on the rise,posing challenges to crowd management and facility design.Based on the systematic understanding of the characteristics of evacuation movement of the elderly,strengthening management and improving design to improve the efficiency of evacuation of the elderly is of great significance to ensure the safety of the elderly group.However,there is a lack of researches on the characteristics of evacuation of the elderly.This article carried out series experiments for the elderly evacuating from typical scenarios,including single-file,corridor and bottleneck.The aim is to understand the evacuation movement characteristic of the elderly,to quantify the movement characteristics between the elderly and college students,to reveal the mechanism of interactions between pedestrians and its influence on evacuation.This research mainly divided into two aspects:1.Considering the one-dimensional,two-dimensional interaction modes between the elderly and the mixed,cooperative interaction modes between the elderly and the young,a series of control experiments were carried out to explore the evacuation characteristics of the elderly.Firstly,the fundamental diagram of the one-dimensional movement process of the elderly in the single-file was obtained,the relationship between headway and speed was revealed.The stepping parameters such as step length,step width and step duration were extracted,and the stopping time and starting forward distance were defined to analyze the evolution characteristics of stop-andgo waves of the elderly.Furthermore,the fundamental diagram of the two-dimensional movement process of the elderly in the corridor scenario and the evacuation efficiency through the bottleneck scenario were quantified.The free speed of the elderly group was counted,and the fundamental diagram and the flow rate of the normalized movement were calculated to form a dimensionless analysis method.The exit reaction time and exit blocking probability of the elderly were analyzed,and the exclusion effect of the elderly on pedestrians and boundary was revealed by interpersonal distance,boundary distance,density distribution and other spatial distribution characteristics.The movement deviation angle was used to reveal the evolution law of movement direction with position and analyze the movement strategy of the elderly.Finally,based on the bottleneck evacuation data of the elderly group,the influence of the mixed and collaborative interaction mode between the elderly and the young on the efficiency of the bottleneck evacuation was clarified,the angle and location parameters of the assisted group were defined and quantified,and the mechanism of the coordinated evacuation movement of the assisted group was revealed.It was found that the distance between the left hand and the right hand and the exit had significant influence on the speed difference and movement direction of the assisted group.2.Based on the experimental study of the evacuation characteristics of the elderly in typical scenarios,the evacuation model of the elderly assisted by the young was constructed,the multi-mode evacuation movement of the elderly was reproduced,and the reliability of the model was verified by empirical data.Parameters for collision-free velocity model were adjusted based on the experimental results.The evacuation time and flow rate of the evacuation for the elderly poplation under different widths and number of pedestrians.The simulation was further popularized and applicated to community endowment evacuation simulation architecture.And the width of traffic facilities design and position of the functional patition were discussed.The feasibility of widening the room exit,corridor and floor exit by 1.25 times to improve evacuation efficiency of the elderly group was verified.Coupling assisted group movement coordination mechanism,considering the exit young to the old speed and direction of migration behavior,constructed the comprehensive evacuation model of the young assisting the elderly,collaborative interaction model in both macroscopic and microscopic parameters with high reliability.The stable space structure and movement characteristics of the assisted group can be well repetition by the model.Further,the model is applied to explore the interaction between a single person and the assisted group and the influence of the left and right hand supporting mode on evacuation.In this paper,the evacuation characteristics of the elderly were studied,such as fundamental diagram,stepping behavior,spatial and temporal distribution,movement strategy,and the quantitative difference between the elderly and the young.The results can provide data support and theoretical basis for the safety design and transformation of access facilities in old people’s buildings.The constructed evacuation model of the young assisting the elderly can provide an effective method for formulating management plans and evacuation strategies in public places with a high proportion of the elderly. |
