Methods for planning and managing a transportation system in an urban area, when exogenous events occur and/or in emergency conditions, have received little attention from transportation system researchers, research institutions and journals. Models and algorithms specified and calibrated for ordinary conditions cannot be directly applied in emergency conditions. In this paper, the main problems developed concern: formalization of the risk problem in a transportation system with an improvement over consolidated quantitative risk analysis models; specification of a system of models for evacuation design and simulation, and in the particular case of path design in emergency conditions; the application of the model to simulate a real system for exposure reduction. The application was developed for an Italian town of about 9,000 inhabitants which was chosen as it has a similar number of potential evacuees to the majority of cases in real events when entire small towns, parts of a city or big buildings had to be evacuated. The curve between vulnerability and exposure is quantitatively represented.
evacuation, network design, risk analysis, simulation
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