Railway/Highway At-Grade Crossing Surface Management: An Overview

This report draws on data from around the United States to describe the features of a successful railway/highway at-grade crossing management program; it emphasizes the highway/trackbed structures and crossing surfaces. Developing a structurally adequate crossing system is imperative, as this will produce a smooth surface and a stable highway/trackbed that prolongs crossings’ lifespans while keeping maintenance costs low and minimizing the number of disruptions encountered by highway and railway traffic. An overview of the guidance issued by several transportation agencies and organizations to facilitate the design and construction of railway/highway at-grade crossings is included here. Equally important to developing a robust network of crossings is defining a clear division of labor between federal, state, and local transportation agencies and railroad companies. As such, this report discusses administrative procedures and state-level regulations that influence railway/highway at-grade crossing practices. This information is presented for AASHTO, AREMA, FRA, FHWA, MUTCD, as well as several states, including Illinois, Indiana, Iowa, Georgia, Michigan, and West Virginia

Effect of Enhanced Trackbed Support on Railway/Highway At-Grade Crossing Performance

This report documents the long-term performance of 89 railway/highway at-grade crossings in Kentucky and adjacent states that contain asphalt underlayment underneath the ballast. Asphalt underlayment increases load carrying capacity for trains and highway vehicles while enhancing the support structure’s waterproofing and confinement. The asphalt underlayment crossings studied were installed at sites that had historically exhibited poor performance and short service lives. Most of the crossing sites evaluated were 10-15 years old; however, their ages ranged up to 30 years. All of the crossings investigated have shown excellent performance since the installation of asphalt underlayments. No crossing failures, such as excessive settlement or mud pumping, have been noted, and the service lives of the crossing surfaces have been significantly improved. Detailed results from periodic inspections are included. A literature survey focuses on eleven public agencies and railroad companies that implement asphalt underlayments. Most of these entities install asphalt underlayments at heavy traffic/tonnage crossings that have routinely shown evidence of weak support leading to inferior performance. This survey, along with the empirical results of this study, indicates that asphalt underlayment, irrespective of material used on crossing surfaces, extends the service life of crossings and improves their performance

Carbon flux through citric acid cycle pathways in perfused heart by 13C NMR spectroscopy

AbstractMathematical models of the TCA cycle derived previously for 14C tracer studies have been extended to 13C NMR to measure the 13C fractional enrichment of [2-13C]acetyl-CoA entering the cycle and the relative activities of the oxidative versus anaplerotic pathways. The analysis is based upon the steady-state enrichment of 13C into the glutamate carbons. Hearts perfused with [2-13C]acetate show low but significant activity of the anaplerotic pathways. Activation of two different anaplerotic pathways is demonstrated by addition of unlabeled propionate or pyruvate to hearts perfused with [2-13C]acetate. In each case, the amount of [2-13C]acetate being oxidized and the relative carbon flux through anaplerotic versus oxidative pathways are evaluated

Recommendations for KYTC’s Railway/Highway At-Grade Crossing Surface Management Practices

An ideal Railway/Highway At-Grade Crossing Management program involves selecting costeffective practices when designing new crossings and rehabilitating existing crossings. This report outlines two strategies to enhance KYTC’s existing program. First, it describes a process that uses decision-option diagrams to optimize the assessment and implementation of engineering solutions in order to restore desired smoothness, minimize settlement in the postconstruction phase, and foster acceptable long-term performance of crossings following their rehabilitation. Decision-option diagrams rely on assessments that are site-specific and based on historical performance, the present observed performance and condition, and the measureable parameters specific to particular crossings. To supplement this process, the second strategy that this report proposes is the establishment of an effective managerial structure at KYTC that streamlines decision-making to ensure that the selected design is properly applied and implemented. Taken together, these proposals will significantly improve the state’s ability to systematically and cost-effectively repair deteriorated crossings

Railway/Highway At-Grade Crossing Surface Rehabilitation Manual: Recommendations and Guides

This Railway/Highway At-Grade Crossing Surface Rehabilitation Manual offers guidance to engineers and project planners for designing, constructing, and managing railway/highway crossing rehabilitation projects. The manual includes information on pre-project administration, project execution, and post-project management and oversight. Suggestions are provided for determining the most cost-effective rehabilitation procedure, techniques to insure the appropriate installation procedures are followed onsite, and instructions for post-project administration and inspection procedures. The primary goal of this manual is to aid with the implementation of a crossing rehabilitation program; all of its guidance underscores the importance of achieving costeffective solutions through the use of best practices to build crossings that are safe and smooth, perform at a high level, and have a long service life, which benefits railroads as well the driving public

The Psychological and Physiological Effects of Music on Athletic Performance

Please view abstract in the attached PDF file