An evacuation model that integrates considerations for fire effects and motion posture
In fire evacuation scenarios,pedestrians frequently face both physical and psychological stress,which can impair their ability to safely evacuate.To mitigate the risk of injury,individuals may resort to adopting specific postures,such as bending or crawling,during the evacuation process.This study endeavors to quantify the impact of individuals'movement postures and their interactions with fire on evacuation dynamics.To accomplish this,an advanced social force model is proposed,which delineates pedestrian movement postures using ellipses of varying sizes.This model integrates both the physiological and psychological effects of fire on individuals,thereby providing a comprehensive understanding of evacuation behaviors.This model showcases enhanced accuracy in simulating the path selection strategies and avoidance behaviors observed among pedestrians navigating around a fire.It empowers pedestrians to strategically devise avoidance paths by considering the current state of the fire,thereby circumventing regions with elevated temperatures and potential hazards.Moreover,the study delves into investigating how crowd density influences evacuation efficiency across three distinct postures.The findings indicate that the movement of Knee and Hand Crawl(KHC)pedestrians remains largely unaffected by variations in density.Conversely,the movement speed of Squatting Walk(SQW)and Stooping Walk(STW)pedestrians decreases as crowd density increases.In low-density crowd scenarios,KHC pedestrians tend to have the longest evacuation times.However,in high-density situations,SQW pedestrians exhibit the lowest evacuation efficiency.Notably,STW pedestrians consistently demonstrate the highest level of evacuation efficiency across various density levels.Furthermore,the study evaluates the impact of fire temperature on pedestrian movement across all three postures,revealing that evacuation times for all crowd types increase with higher temperatures.Notably,the SQW group experiences the most pronounced escalation in evacuation time,whereas the KHC group demonstrates the lowest evacuation efficiency at cooler temperatures.Beyond a certain temperature threshold,the SQW group endures the longest evacuation times among the three postures.Moreover,as temperature rises,the maximum deviation distance of the crowd also increases.Initially,the STW crowd exhibits the smallest maximum deviation distance at lower temperatures.However,this distance rapidly expands with temperature increases,eventually surpassing the maximum deviation distances of the other two postures.The study simulated the effects of fire location and pedestrian hazard sensitivity on path selection,demonstrating that the proportion of pedestrians choosing safer paths gradually increases and eventually stabilizes at 1 as the disparity in path risk widens and pedestrian hazard sensitivity intensifies.
public safetypedestrian safetymotion posturesfire evacuationevacuation modelling
万方数据
维普
