Discrete and continuous evacuation simulation models for rail tunnel evacuation: a comparison study

The damages and loses caused by rail tunnel accidents are usually unbelievable serious even though these events are relatively rare in reality. Evacuation simulation models for rail tunnels could usually be classified into discrete and continuous types. Using these two types of models to simulate the same rail tunnel evacuation process may lead to different and interesting results since the modelling techniques of these two types of models are obviously different from each other and the geometry of rail tunnels usually involves longnarrow walkways which are challenging to be accurately modelled. Therefore, it would be interesting and necessary to compare the differences between these models on modeling rail tunnel evacuations and to identify how the basic rules of these models are affecting the simulation results. This paper compares two typical evacuation simulation models, one is a discrete model and another is a continuous model, on simulating a same set of hypothetical rail tunnel evacuation scenarios. Tunnels with different dimensions of “walkways” and “cross-passageways” are considered. Typical quantitative pedestrian flow indicators such as the egress time, flow rate, the density distribution etc. are analyzed and compared. Simulation parameters which are particularly sensitive to the simulation results are discussed. This study would provide insights for model users or researchers for understanding the differences of the underlying modeling rules in these models.