Tank Car Design Research Articles

Derailment Analysis for Prediction of Damage and Probability of Release for Novel Railroad Tank Car Designs

Over the past 15 years, there has been substantial research performed to improve the safety of tank cars carrying hazardous materials. This has included a series of full-scale tank car impact tests and the development of impact/puncture models capable of evaluating the performance of existing and novel tank car designs under specific impact conditions. In parallel, statistical information was developed on tank car performance based on data from past accidents. However, such data cannot predict the performance of novel tank car designs involving new materials and configurations. This paper presents an innovative analytical framework to address this gap by simulating railroad tank cars behaviors under various train accident and rolling stock features. The finite element method-based simulation model is developed to generate impact forces on railcars after the initiation of train derailments. The results of the modeling were compared, validated, and calibrated with the real-world train derailment to assure the practicality of the analytical tool. This research is novel as it is the first quantitative, analytical methodology that can accurately and practically assess the physical behaviors of railcar movements and impact forces in train derailments. The results of this study provide new and important information for tank car performance in train derailments, which contributes to the literature in structural modeling of rail tank cars. It also specifies an approach to building a bridge between analytical methods and real-world scenarios and data for estimating tank car conditional probability of release (a frequently used metric for hazardous materials transportation safety).

DYNAMIC FEATURES OF STANDARD TANK CARS ON CURVED TRACK SECTIONS

[For the English abstract and full text of the article please see the attached PDF-File (English version follows Russian version)].ABSTRACT Nature of interaction of wheel sets of four-axle and eight-axle tank cars with rails when driving in curves of railway track is considered, including specifics of longitudinal and transverse elastic ties of wheel sets with bogie’s side frames. The results of dynamic performance studies (coefficient of dynamic addition of vertical forces on sprung weight and transverse frame force) of tank cars in curves with radii of 350 and 650 m are provided. It follows that eight-axle tank car design under the terms of traffic safety from the point of view of dynamics is at the same level as a four-axle one, therefore, can be used without restriction on all railways under the same rules of maintenance for undercarriages of tank cars of both types. Keywords: railway, theoretical mechanics, tank car, wheel sets, rails in curves, dynamic performance, elastic and frictional bonds, unextinguished transverse acceleration, coefficient of dynamic addition of vertical forces, frame force, comparative analysis. REFERENCES 1.Verigo, M. F.Interaction of track and rolling stock in curves of small radius and the fight against side wear of rails and wheel flanges [Vzaimodejstvie puti i podvizhnogo sostava v krivyh malogo radiusa i bor’ba s bokovym iznosom rel’sov i grebnej koljos]. Moscow, PTKB CP MPS publ., 1997, 207 p. 2. Anisimov, P. S. Methods of Evaluation of the Impact of Freight cars on the Track. World of Transport and Transportation, Vol.12, 2014, Iss.1, pp.24-32. 3.Vershinskiy, S.V., Danilov, V.N., Khusidov, V. D. The dynamics of the car [Dinamika vagona]. Moscow, Transport publ., 1991, 360 p. 4.Anisimov, P.S., Zhelnin, G.G., Kulikovskiy, B. S. Permissible speed of eight-axle tanks dimensions TC [Dopuskaemye skorosti dvizhenija vos’miosnyh cistern gabarita Tc]. Trudy MIIT, 1986, Iss.780, pp.10-24. 5.Anisimov, P.S., Grachiova, L. O. Tests of eight-axle tanks for BAM [Ispytanija vos’miosnyh cistern dlja BAMa]. Zheleznodorozhnyj transport, 1986, Iss.5, pp.35-36.

Generalized railway tank car safety design optimization for hazardous materials transport: Addressing the trade-off between transportation efficiency and safety

North America railways offer safe and generally the most economical means of long distance transport of hazardous materials. Nevertheless, in the event of a train accident releases of these materials can pose substantial risk to human health, property or the environment. The majority of railway shipments of hazardous materials are in tank cars. Improving the safety design of these cars to make them more robust in accidents generally increases their weight thereby reducing their capacity and consequent transportation efficiency. This paper presents a generalized tank car safety design optimization model that addresses this tradeoff. The optimization model enables evaluation of each element of tank car safety design, independently and in combination with one another. We present the optimization model by identifying a set of Pareto-optimal solutions for a baseline tank car design in a bicriteria decision problem. This model provides a quantitative framework for a rational decision-making process involving tank car safety design enhancements to reduce the risk of transporting hazardous materials.

Communication and Interpretation of Results of Route Risk Analyses of Hazardous Materials Transportation by Railroad

Route risk analysis of hazardous materials transportation by railroad is receiving considerable new attention from industry and government. Such analyses are necessary for effective public policy and development of rational risk management strategies. However, route risk analysis is complex and generates results that can be difficult to properly interpret. Risk analyses are intended to provide risk managers with objective information about how to effectively manage risk and the most effective options to reduce it. This paper uses results from a quantitative risk analysis of hazardous materials shipped by rail to develop and illustrate several new techniques to present, interpret, and communicate risk results more effectively. The analysis accounted for the major factors affecting risk: infrastructure quality, traffic volume, and population exposure along shipment routes, as well as tank car design and product characteristics. Approaches for system-level and route-specific analyses are presented. Both absolute and normalized estimates of risk provide useful information. The question of interest and the user affects which type of information is most useful for effective decision making. Various graphical techniques enable risk metrics to be compared and contrasted, either in a geographic context or independent of it, depending on which is most useful. Identifying the locations that account for the highest concentration of risk and understanding the contributing factors will also clarify the mutual roles of carriers, shippers, and municipalities along a route in regard to risk management, reduction, and mitigation options. In addition, the techniques presented in this paper may also be useful for regulators and researchers who might be interested in a broader view of risk analysis at the network level.

Release Risk and Optimization of Railroad Tank Car Safety Design

The performance metric for tank cars and other hazardous materials vehicles involved in accidents has generally been conditional probability of release given involvement in an accident. This metric considers the probability of a release event occurring but does not take into account the quantity of product lost in a release incident. In this paper, a new metric termed “release risk” is introduced; it is defined as the expected value of the quantity lost from a tank car given that it is in an accident. The quantity of product lost varies depending on the part of the car that is damaged in an accident; consequently, use of release risk can affect how different modifications in tank car design are considered. The metric was developed in terms of tank-damage-caused and non-tank-damage-caused releases. It was found that tank-damage-caused releases had a higher release risk than non-tank-damage-caused releases. Important elements considered are the probabilities of release and the expected quantities of release from the tank components and non-tank components of a tank car, and the effect of increasing tank thickness in increasing accident exposure and decreasing expected quantity of release. The release risk metric is also used as the objective function in a tank thickness optimization model. The results suggest that release risk may be a useful means of assessing the relative benefits of different tank car safety design modifications.

Release Risk and Optimization of Railroad Tank Car Safety Design

The performance metric for tank cars and other hazardous materials vehicles involved in accidents has generally been conditional probability of given involvement in an accident. This metric considers the probability of a event occurring but does not take into account the quantity of product lost in a incident. In this paper, a new metric termed release is introduced; it is defined as the expected value of the quantity lost from a tank car given that it is in an accident. The quantity of product lost varies depending on the part of the car that is damaged in an accident; consequently, use of risk can affect how different modifications in tank car design are considered. The metric was developed in terms of tank-damage-caused and non-tank-damage-caused releases. It was found that tank-damage-caused releases had a higher risk than non-tank-damage-caused releases. Important elements considered are the probabilities of and the expected quantities of release...

DEVELOPMENT OF THE GAS TANKS OF THE NEW GENERATION, EQUIPPED WITH PROTECTIVE DEVICES FOR INCREASED POWER CONSUMPTION

The response and the stress-strain state of new generation gas tank-car design elements at emergency impacts in the head are investigated. The tank-car is equipped with tank head protection devices of safety shields with cellular energy absorbing element type. Efficiency of their use at emergency loading is shown.

Urethane Foam 'Insealation' cuts production costs, improves tank car design

Urethane Foam 'Insealation' cuts production costs, improves tank car design