Reference values for railway sidings track geometry

Railway sidings are operated at speeds much lower than those used on national railway lines; a typical speed is 6 km/h. In establishing reference values for maintenance of railway infrastructure in terms of the geometry for such operating conditions, it is noted that both national and European regulations do not provide specific information regarding railway sidings. The overall objective of the research is, therefore, the definition of possible reference values for track geometry, based on those adopted by European rail networks (European and national standards), which can guarantee the appropriate security level for low speed operation typical of railway sidings connected to the national network. The basic principle in defining these values is the maximization of technical-economic efficiency and the maintenance of the acceptability of the risk associated to railway operation. The research results can therefore provide useful information about the cost-effective management of maintenance and safe operation for railway sidings. For this purpose, the approach was inspired to that of Regulation 402/2013, which defines at European level a common safety method for risk analysis. Quantification of probabilities and damages should be based on simulation models because the available statistics do not allow significant results to be inferred. However, the research sector has not yet produced a consolidated modelling. For these reasons, and since it is not possible to quantify probabilities reliably, the proposals resulting from this research are based on the identification of situations where it can be shown that the hazard probability remains unchanged. The approach used to formulate possible reference values valid outside of national networks (railway sidings) is based on an understanding of the underlying principles of the codes of good practice, on the formulation of hypotheses conform to the same principles, and the proposals about mitigative measures of risk associated to the use of different reference values, such as to keep the risk of the railway within the limits of acceptability, acting conservatively so as to keep unchanged, or reduce, the probability of hazardous events.The assessment parameters, object of the first phase of the research referred to in this work and used here as an example, are longitudinal level and alignment of railway track. In the case of vehicles running at low speed, the study was conducted by varying the magnitude of the reference values by using values that belong to external intervals with respect to those in accordance with European and national codes of good practice, examining the corresponding effects on the physical quantities related to safety. The effects of their variations on the wheel-rail interaction forces were studied using a simple dynamic model (with one degree of freedom) and a random generated excitation given by track defectiveness and the corresponding random response in terms of vertical and lateral contact forces (Q and Y)

Advanced model-based risk reasoning on automatic railway level crossings

Safety is a core issue in the railway operation. In particular, as witnessed by accident/incident statistics, railway level crossing (LX) safety is one of the most critical points in railways. In the present paper, a Bayesian network (BN) based framework for causal reasoning related to risk analysis is proposed. It consists of a set of integrated stages, namely risk scenario definition, real field data collection and processing, BN model establishment and model performance validation. In particular, causal structural constraints are introduced to the framework forthe purpose of combining empirical knowledge with automatic learning approaches, thus to identify effective causalities and avoid inappropriate structural connections. Then, the proposed framework is applied to risk analysis of LX accidents in France. In details, the BN risk model is established on the basis of real field data and the model performance is validated. Moreover, forward and reverse inferences based on the BN risk model are performed to predict LX accident occurrence and quantify the contribution degree of various impacting factors respectively, so as to identify the riskiest factors. Besides, influence strength and sensitivity analyses are further carried out to scrutinize the influence strength of various causal factors on the LX accident occurrence likelihood and determine which factors the LX accident occurrence is most sensitive to. The main outputs of our study attest that the proposed framework is sound and effective in terms of risk reasoning analysis and offers significant insights on exploring practical recommendations to prevent LX accidents

Formulating a Strategy for Securing High-Speed Rail in the United States, Research Report 12-03

This report presents an analysis of information relating to attacks, attempted attacks, and plots against high-speed rail (HSR) systems. It draws upon empirical data from MTI’s Database of Terrorist and Serious Criminal Attacks Against Public Surface Transportation and from reviews of selected HSR systems, including onsite observations. The report also examines the history of safety accidents and other HSR incidents that resulted in fatalities, injuries, or extensive asset damage to examine the inherent vulnerabilities (and strengths) of HSR systems and how these might affect the consequences of terrorist attacks. The study is divided into three parts: (1) an examination of security principles and measures; (2) an empirical examination of 33 attacks against HSR targets and a comparison of attacks against HSR targets with those against non-HSR targets; and (3) an examination of 73 safety incidents on 12 HRS systems. The purpose of this study is to develop an overall strategy for HSR security and to identify measures that could be applied to HSR systems currently under development in the United States. It is hoped that the report will provide useful guidance to both governmental authorities and transportation operators of current and future HSR systems

Application of Statistical Analysis for Risk Estimate of Railway Accidents and Traffic Incidents at Level Crossings

Abstract This paper deals with applying statistical analysis of traffic safety to analyze the risks at level crossings. The social costs of railway accidents and traffic incidents at level crossings are very high and lead to a reduction in the levels of traffic safety. In addition to the consequences reflected in the loss of human lives, injuries, and disabilities, the stress and trauma of direct participants in traffic, accidents, and incidents at level crossings cause huge property and economic losses and significant primary and secondary traffic delays. The traffic safety analysis was conducted on 2128 level crossings, which are differently protected on the lines Joint Stock Company for Public Railway Infrastructure Management ”Serbian Railway Infrastructure” with statistical data of accidents in the Republic of Serbia from 2007 to 2017. The paper analyzes the obtained results using the methods of descriptive and inferential statistics to define measures of possible improvement of safety levels at the obtained critical level crossings. Also, a proposal was made for improving and raising the level of safety on level crossings through innovative education of direct participants in traffic

Safety concepts to enable autonomous train operations in semi-restricted industrial areas

The work performed has been enabled by Business Finland, which provided funding for a research project ‘Autonominen juna -kehityshanke’ - VTT (45715/31/2020), which included collaboration with Proxion Oy, Electric Power Finland Oy, and Steel Wheel Oy for the development of autonomous train in industrial sites. Typically, these sites have small internal rail network forlow-speed transportation of raw materials, semifinished goods, and final products. Since most of the traffic within these sites is caused by the trucks and trains of the industrial site itself, and since the vehicles and persons from outside would need permission to enter, many of such sites can be described as semi-restricted.The study considers other (manual) train traffic in semi-restricted industrial areas but does not consider the driving of an autonomous train on the public main line. The study had two main research objectives. The first objective was to identify and analyse safety risks related to the daily operation of the autonomous train on its route in a semi-restricted industrial area: charging / refuelling station, loading / unloading places, railway switches and level crossings. The second objective was to define concepts to secure the path of an autonomous train and principles to control level crossings and their safety-related systems in three different train traffic control concepts:− An autonomous train has a static local permit in a semi-restricted industrial area− The autonomous train has a dynamic local permit in a semi-restricted industrial area− The rail yard traffic control sets the access permit for the autonomous train in a semi-restricted industrial areaThis report summaries the analysis of new safety risk related to autonomous train operations in semi-restricted industrial areas, including the concepts for safe pathways and safe level crossing controls for autonomous train operations

Safety concepts to enable autonomous train operations in semi-restricted industrial areas

The work performed has been enabled by Business Finland, which provided funding for a research project ‘Autonominen juna -kehityshanke’ - VTT (45715/31/2020), which included collaboration with Proxion Oy, Electric Power Finland Oy, and Steel Wheel Oy for the development of autonomous train in industrial sites. Typically, these sites have small internal rail network forlow-speed transportation of raw materials, semifinished goods, and final products. Since most of the traffic within these sites is caused by the trucks and trains of the industrial site itself, and since the vehicles and persons from outside would need permission to enter, many of such sites can be described as semi-restricted.The study considers other (manual) train traffic in semi-restricted industrial areas but does not consider the driving of an autonomous train on the public main line. The study had two main research objectives. The first objective was to identify and analyse safety risks related to the daily operation of the autonomous train on its route in a semi-restricted industrial area: charging / refuelling station, loading / unloading places, railway switches and level crossings. The second objective was to define concepts to secure the path of an autonomous train and principles to control level crossings and their safety-related systems in three different train traffic control concepts:− An autonomous train has a static local permit in a semi-restricted industrial area− The autonomous train has a dynamic local permit in a semi-restricted industrial area− The rail yard traffic control sets the access permit for the autonomous train in a semi-restricted industrial areaThis report summaries the analysis of new safety risk related to autonomous train operations in semi-restricted industrial areas, including the concepts for safe pathways and safe level crossing controls for autonomous train operations