The barrel life of a solid armature rail gun is a critical issue. Arcing along the barrel pathway at the interfaces between the armature and the rails produces severe damage. The ability to protect the rails and yet provide sufficient electrical contact to sustain arc-free high-current flow is desirable. This thesis investigates the use of liquid metal as an interface material between the sliding electrical contact surfaces of the armature and the barrel rails. Experiments were conducted with the Naval Postgraduate Schoolαs 4-inch Rail Gun and liquid metal interface coatings were applied to the armatures. Results indicated that the liquid interface protects the rails and projectile surfaces for static electrical contact. Apparatus has been design to investigate sliding electrical contact between armature and rails in a controlled manner. New rails with a novel Adamy-Maier grooved rail design were fabricated to facilitate coating rails. Various groove patterns have been designed to control the current flow through the rails and across the interface surfaces, while maintaining lateral stability and interface integrity. These experiments are still in progress at the time of this writing. / US Navy (USN) author

This study evaluates specific variables that influence rail freight operating costs for line haul movements. This paper gives planners a mechanistic method to determine rail costs on a single corridor while analyzing the effects of different variables on the overall operating costs. Planners evaluating the benefits of rail operations face two problems; what is the route alignment and what rail costs are derived for this alignment? This paper also reports on a promising method to measure track alignment—specifically grades – which obviates the need to work with railroad companies to determine track alignments for preliminary multimodal analysis. Complete rail freight transportation assessment can be determined from the proposed two methods, allowing more accurate planning to be done in the area of freight movement. / text

Thesis (M.S. in Applied Physics) Naval Postgraduate School, December2001. / Thesis Advisor(s): Maier, II, William B. "December 2001." Includes bibliographical references (p. 25-29). Also available online.

In recent years there has been continuous increase of axle loads, tonnage, train speed, and train length which has increased both the productivity in the rail sector and the risk of rail breaks and derailments. Rail operating risks have been increasing due to the increased number of axle passes, sharper curves, wear-out of rails and wheels, inadequate rail-wheel grinding and poor lubrication and maintenance. Rolling contact fatigue (RCF) and wear are significant problems for railway companies. In 2000, the Hatfield accident in the UK killed 4 people, injured 34 people and led to the cost of £ 733 million (AUD$ 1.73 billion) for repairs and compensation. In 1977, the Granville train disaster in Australia killed 83 people and injured 213 people. These accidents were related to rolling contact fatigue, wear and poor maintenance. Studies on rail wear and lubrication, rolling contact fatigue and inspection and rail grinding analyse and assess the asset condition to take corrective and preventive measures for maintaining reliability and safety of rail track. Such measures can reduce the operational risks and the costs by early detection and prevention of rail failures, rail breaks and derailments. Studies have so far been carried out in isolation and have failed to provide a practical solution to a complex problem such as rail-wheel wearfatigue-lubrication-grinding-inspection for cost effective maintenance decisions. Therefore, there is a need to develop integrated economic models to predict expected total cost and operational risks and to make informed decisions on rail track maintenance. The major challenges to rail infrastructure and rolling stock operators are to: 1. keep rolling contact fatigue and rail-wheel wear under controllable limits, 2. strike a balance between rail grinding and rail lubrication, and 3. take commercial decisions on grinding intervals, inspection intervals, lubrication placements, preventive maintenance and rail replacements. This research addresses the development and analysis of an integrated model for assessment of operational risks in rail track. Most significantly, it deals with problems associated with higher axle loads; wear; rolling contact fatigue; rail defects leading to early rail replacements; and rail breaks and derailments. The contribution of this research includes the development of: failure models with non-homogenous Poisson process and estimation of parameters. economic models and analysis of costs due to grinding, risks, downtime, inspection and replacement of rails for 23, 12, 18 and 9 Million Gross Tonnes (MGT) of traffic through curve radius 0-300, 300-450, 450-600 and 600-800 m; and application of results from this investigation to maintenance and replacement decisions of rails. Cost savings per meter per year are: * 4.58% with 12 MGT intervals compared to 23 MGT intervals for 0-300 m * 9.63% with 12 MGT intervals compared to 23 MGT intervals for 300-450 m * 15.80% with 12 MGT intervals compared to 23 MGT intervals for 450-600 m * 12.29% with 12 MGT intervals compared to 23 MGT intervals for 600-800 m. a lubrication model for optimal lubrication strategies. It includes modelling and economic analysis of rail wear, rail-wheel lubrication for various types of lubricators. Cost effectiveness of the lubricator is modelled, considering the number of curves and the total length of curves it lubricates. Cost saving per lubricator per year for the same curve length and under the same curve radius is: * 17% for solar wayside lubricators compared to standard wayside lubricators. simulation model for analysis of lubrication effectiveness. Cost savings per meter per year for: * 12 MGT grinding interval is 3 times for 0-450 m and 2 times for 450-600 m curve radius with lubrication compared to without lubrication. * 23 MGT grinding interval is 7 times for 0-450 m and 4 times for 450-600 m curve radius with lubrication compared to without lubrication. a relative performance model, total curve and segment model. an inspection model for cost effective rail inspection intervals. Cost savings per year for same track length, curves and MGT of traffic: * 27% of total maintenance costs with two inspections, compared to one inspection considering risk due to rail breaks and derailments. a risk priority number by combining probability of occurrence, probability of detection and consequences due to rail defects, rail breaks and derailments. integrated model combining decisions on grinding interval, lubrication strategies, inspection intervals, rectification strategies and replacement of rails. Cost saving per meter per year for 12 MGT is: * 5.41% of total maintenance costs with two inspections, compared to one inspection considering risk due to rail breaks and derailments. * 45.06% of total maintenance costs with lubrication for two inspections, compared to without lubrication. Cost saving per meter per year for 23 MGT is: * 5.61% of total maintenance costs with two inspections, compared to one inspection considering risk due to rail breaks and derailments. * 68.68% of total maintenance costs with lubrication for two inspections, per year compared to no lubrication. The thesis concludes with a brief summary of the contributions that it makes to this field and the scope for future research in wear-fatigue-lubrication-grinding-inspection for maintenance of rail infrastructure.

The planning and specification of rail grinding activities using measured rail profiles normally involves a comparison between the existing and desired rail profiles within a rail segment. In current practice, a somewhat subjective approach is used to select a measured profile – usually located near the midpoint of the segment – that represents the profiles throughout the rail segment. An automated procedure was developed to calculate a representative average (mean) rail profile for a rail segment using industry-standard rail profile data. The procedure was verified by comparing the calculated average to an expected profile. The procedure was then validated by comparing the calculated average profiles of 42 in-service rail segments (10 tangents and 32 curved segments) to the corresponding subjectively chosen median rail profiles for each segment. Overall, the validation results indicated that the coordinates comprising the mean and median profiles differed by less than one percent on average. As expected, stronger agreement was observed for tangent rail segments compared to curved rail segments. Thus, the validation demonstrated that the procedure produces comparable results to current practice while improving the objectivity and repeatability of the decisions that support rail-grinding activities. / February 2017

Rates of car ownership in the United States exceed that of all other large nations in the world. This high rate contributes to the unexpressed demand for road space that renders highway expansion useless as a strategy for decreasing traffic congestion. It also necessitates the provision of on-site parking in residential buildings, decreasing the affordability of housing in urban areas. Furthermore, the curb-side parking needed to make room for the high number of cars in the country takes away space that could be used for bike lanes, transit lanes, or widened sidewalks. Therefore, the United States could benefit from a reduction in rates of household car ownership. In this paper, I use cross-sectional data from the National Highway Transportation Survey to determine the impact on heavy and light rail on car ownership in American cities. I find that the presence of heavy rail is associated with a lower rate of car ownership, while the presence of light rail is not.

This report assesses the current and future freight conditions in Texas, and how more freight will need to be transported by rail to keep up with the population and economic trends. Public-private partnerships are necessary to accommodate this surge in growth in order to make it financially feasible for both the public and private sectors. The intent of this report is to introduce the concept of freight rail public-private partnerships in order to relate it to the State of Texas to help accommodate growth. Two case studies will be discussed as examples of successful public-private partnerships where freight rail expansion was feasible. At the end of each case study, there is a section for implications in Texas’ rail system. A series of interviews with public and private stakeholders will portray the sides of both sectors as to why freight rail publicprivate partnerships are difficult to achieve in Texas. Finally, some recommendations will be made for Texas based on the case studies and interviews. / text

Commuter rail infrastructure often adds value to neighboring properties. The best methods to measure changes in values require baseline data from a year prior to system implementation. The current planning of a commuter rail in Austin, TX presents the need to document property values for future studies. The report records 2005 property values from Travis and Williamson Central Appraisal Districts, using GIS to group the data by various distances away from the proposed train stations. In addition, a large set of secondary improvement data and census demographic information about each site has been accumulated. Future researchers will be able to conduct matched-pair and multivariable regression models with the data, and rely on the station descriptions for a solid understanding of the sites and their relationships. / text

Study Supervisor: Dr Jan Kruger Completed: 2008 / Developing an explanatory quantitative statistical model based on time series analysis and regression models for time series, for explanation of the factors impacting ticket sales and therefore fare revenue in commuter rail in South Africa and using this quantitative model(s) to forecast demand in commuter rail usage for fare revenue purposes.

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