Methodology for risk analysis in railway tunnels using monte carlo simulation

Abstract

In the context of safety analyses for railway tunnels, various efforts have been made to try to identify and evaluate the possible consequences of undesired events. Very few of these efforts have proposed techniques or methodologies allowing the risks involved to be quantified. By counting on a Quantitative Risk Analysis (QRA) methodology applied in the planning of railway tunnels, we would be able to know and quantify the potential consequences of these risks. The present paper sets out a QRA Methodology, applied to railway tunnels, fundamentally based on the analysis and combination of scenarios, using the "Event Tree" and "Monte Carlo Simulation (MCS)" techniques. The basic tools for the methodology are the "PrecisionTree" and "@RISK" software programmes that allow events with uncertain occurrence probabilities to be analyzed using the formulation of decision-tree models and the risk assessed through the use of Monte Carlo simulations. The development of a QRA methodology, based on the use of "Event Tree" and "MCS" techniques, offers a powerful and effective way to quantify the risks of possible fatalities in railway tunnels. The application of the QRA methodology in the Planning or Conceptual Engineering phases of a project constitutes a fundamental tool as it allows the possible infrastructure types or solutions to be assessed and compared from the standpoint of safety in order to select the Tunnel System to be implemented. © 2012 WIT Press.