Agent-Based Simulation of Heterogeneous Crowd Flows in Critical Infrastructures During Emergencies

The scope of this work was the development of a model able to simulate the flows and behaviours of heterogeneous crowds in a large transport hub, both in normal conditions and during an emergency, like a terrorist attack. These places are indeed also so-called "soft targets," public spaces that are preferred targets of terrorists because they provide them with the opportunity to maximize casualties and publicity. Different modelling approaches were investigated, and finally, agent-based modelling and the BDI (belief-desire-intention) architecture were selected. Several scenarios were also identified to simulate the crowd behaviour. Flowcharts were developed to model users' actions and interactions while statecharts modeled emergency conditions and behavioural changes. Simulations were then used to identify weak points in the infrastructure and to analyse the evacuation times for each user category investigated. Finally, various solutions were proposed and simulated to improve crowd flows and reduce evacuation times.