Risk Analysis of Cross Wind on HS/HC Rome-Naples Railway Line

When a train is running on a railway line, one of the most critical problem related to safety is the risk of overturning associated to the cross wind action. Within the new European Technical Specification for High Speed Interoperability (TSI), the cross wind represents one of the main themes: the standard defines the limit values for the Characteristic Wind Curves (CWC) that represents the wind speed that lead the vehicle to the overcoming of specific safety limits. Nevertheless, by the side of infrastructure, the TSI requires the infrastructure manager to identify the most critical sections of the line but no specific methodologies are defined. In order to analyse the problem from the point of view of the infrastructure, a risk analysis, based on the study of the wind-train interaction, is needed: this study depends on both the wind characteristics along the line and the dynamic behaviour of the train. The second part the European project “Aerodynamic in Open Air” (AOA), was specifically devoted to assess the risk analysis on high speed lines related to cross wind effects (Ref. [5]). Within the AOA project, for the meteo analysis specific numerical tools, more or less refined, have been developed but, at the present, a common standardized method has not been assessed. About the train stability, the CWC are a commonly accepted method to define the overturning limit even if discrepancies remain if they have to be evaluated through stochastic or deterministic values. As a consequence, the risk assessment that consists in combing the information coming from the meteo analysis and from the CWC’s, at present, is still under definition. This paper leads to the comparison between two approaches for the risk analysis developed within the AOA project: a stochastic methodology (STM, Ref. [1]) and a deterministic methodology (DEM, Ref. [8]). The two methods will be applied to samples of the new RomeNaples high speed line.