A risk-based approach for crowd evacuation performance evaluation under metro fire

Abstract

This paper aims to evaluate the crowd evacuation performance in a metro fire by using the limit state equation to describe the egress process. The limit state equation is established by the available time margin in fire evacuation, which comprises the evacuee's response time, behaviour time and movement time to an exit. Here, the available time margin in a fire evacuation is determined by the duration of time the smoke takes to exceed the evacuee's respiration level, the time that the smoke is detected by fire alarm and the time that the evacuee needs to respond and move to an exit during evacuation. Further, Monte Carlo simulation approach has been employed to integrate the fatality rates and the probabilities of occurrence of different scenarios in a typical metro in Xiaobailou station of station-Tianjin Line 1. Through this case study, it is shown that the evacuee's response time, behaviour time and movement time to exits can be integrated in a stochastic process model.