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From page 662... ... 14-i Chapter 14 -- LRT Track and Trackway Maintenance Table of Contents 14.1 PURPOSE 14-1 14.2 TRACKWORK STANDARDS 14-1 14.2.1 Track Construction Standards 14-1 14.2.2 Track Maintenance Standards 14-1 14.2.3 Track Safety Standards 14-2 14.3 ACCEPTANCE 14-3 14.4 WORKING SAFELY ON THE RAILWAY 14-3 14.4.1 Track Protection 14-4 14.4.2 Flag Persons 14-4 14.4.3 FRA 214 Regulations (If Applicable) 14-4 14.4.4 Risk Analysis 14-5 14.4.5 Preparatory Work 14-5 14.4.6 Profile of a Safe Person 14-5 14.5 INSPECTING THE SYSTEM 14-5 14.5.1 How Often? Read the entire page →
From page 663... ... Track Design Handbook for Light Rail Transit, Second Edition 14-ii 14.6.3.4 Snow Removal 14-14 14.6.3.5 Repair Broken Rail 14-14 14.6.3.6 Replace Worn-Out Rail 14-15 14.6.3.7 Replacement of Parts in Embedded Specialwork 14-15 14.6.3.8 Rail Grinding in Embedded Track 14-15 14.6.4 Direct Fixation Track Maintenance Activities 14-16 14.6.4.1 Tighten Bolts 14-16 14.6.4.2 Rail Clip Maintenance 14-16 14.6.4.3 Housekeeping 14-17 14.6.4.4 Regauging Track for Rail Wear 14-17 14.6.4.5 Repair Cracked and Spalling Concrete 14-18 14.6.4.6 Repair Caulking 14-18 14.6.4.7 Repair of Broken Rail 14-18 14.6.4.8 Replacing Rail Fasteners 14-18 14.6.4.9 Rail Fastener Anchor Insert Replacement 14-19 14.6.4.10 Replace Continuous Welded Rail 14-19 14.6.4.11 Replace Parts in Special Trackwork 14-20 14.6.5 Ballasted Track Maintenance Activities 14-20 14.6.5.1 Ballast Maintenance 14-20 14.6.5.2 Surface Track 14-20 14.6.5.3 Repair Deflector Ramps at Crossings 14-21 14.6.5.4 Replace Pads and Insulators on Cross Ties 14-21 14.6.5.5 Replace Cross Ties (Timber and Concrete) 14-21 14.6.5.6 Vegetation Control 14-21 14.6.5.7 Drainage Maintenance 14-22 14.6.5.8 Yard Cleaning 14-22 Read the entire page →
From page 664... ... 14-1 CHAPTER 14 -- LRT TRACK AND TRACKWAY MAINTENANCE 14.1 PURPOSE The designer should understand that once the system is designed, built, and turned over to the owner, it will need to be maintained. All too often, the focus of the designers and constructors is only on building the project with insufficient attention to the interests of the maintainers. Read the entire page →
From page 665... ... Track Design Handbook for Light Rail Transit, Second Edition 14-2 and classes of track. These standards will be unique to each transit property based on its needs and objectives. Read the entire page →
From page 666... ... LRT Track and Trackway Maintenance 14-3 While the Federal Railroad Administration has a comprehensive set of track safety standards (see 49CFR213) that are a useful reference, they technically do not apply to urban rail transit systems that are not connected to the general railroad system. Read the entire page →
From page 667... ... Track Design Handbook for Light Rail Transit, Second Edition 14-4 office, with a safety briefing. The purpose of the briefing is to make certain that everybody understands the activity to be performed, the procedures for doing it in a safe and approved manner, and, in the event of an emergency, what to do to minimize injury or other harm. Read the entire page →
From page 668... ... LRT Track and Trackway Maintenance 14-5 14.4.4 Risk Analysis Mitigating risk to a safe level will reduce accidents. Thinking about what could happen might just save someone's life. Read the entire page →
From page 669... ... Track Design Handbook for Light Rail Transit, Second Edition 14-6 stipulates that tracks used in revenue service should be inspected at least once a week and that other tracks should be inspected monthly. An interval of at least 3 but not more than 11 calendar days must elapse between inspections. Read the entire page →
From page 670... ... LRT Track and Trackway Maintenance 14-7 around transit parameters. Differences in back-to-back wheel gauge and the resulting incompatibility with narrow flangeways are distressingly common occurrences. Read the entire page →
From page 671... ... Track Design Handbook for Light Rail Transit, Second Edition 14-8 Corrugation is characterized by two main parameters. One is the length of the "waves." This is measured from crest to crest or valley to valley. Read the entire page →
From page 672... ... LRT Track and Trackway Maintenance 14-9 valleys. Careful monitoring of corrugation growth rates are necessary to determine an optimum grinding interval, which may be the time required for the corrugation amplitude to increase by a factor of two or three relative to some reference condition. Read the entire page →
From page 673... ... Track Design Handbook for Light Rail Transit, Second Edition 14-10 Working condition requirements could include the following: • Time of day limitations. Can track time be made available during the day or will all of the grinding need to be done on nights and weekends? Read the entire page →
From page 674... ... LRT Track and Trackway Maintenance 14-11 − Any limitations the equipment may have, such as the minimum radius the equipment can traverse and whether it can operate on non-standard gauge track. − Environmental controls such as the dust collection, fire protection, and spark- arresting systems, as well as the system for collection and disposal of rail grinding debris. Read the entire page →
From page 675... ... Track Design Handbook for Light Rail Transit, Second Edition 14-12 • Rail grinding in embedded track has unique challenges; see Article 14.6.3.8 for a detailed discussion of these issues. 14.6.2.3 Repair Welding and Grinding of Switches and Frogs This is another important activity that will allow the switch points and frogs to achieve the maximum life possible. Read the entire page →
From page 676... ... LRT Track and Trackway Maintenance 14-13 14.6.2.5.1 The Federal Railroad Administration The Federal Railroad Administration (FRA) regulates trackwork that is part of the general railroad system of transportation and has some oversight of tracks that, while they are not part of the general railroad system, are proximate to FRA-regulated tracks. Read the entire page →
From page 677... ... Track Design Handbook for Light Rail Transit, Second Edition 14-14 At one LRT system in Germany, a specially equipped rail grinding vehicle also includes a flangeway scraping tool with a vacuum system for cleaning the flangeways of groove rails. Such a system might not work as well on embedded tracks using tee rail because the scraping tool might damage the pavement and the rail boot or other rail isolation system. Read the entire page →
From page 678... ... LRT Track and Trackway Maintenance 14-15 The concrete surface must be saw cut on either side of the rail a distance that will expose the fastening system when the concrete is removed. The concrete is then chopped out to a depth near the base of rail. Read the entire page →
From page 679... ... Track Design Handbook for Light Rail Transit, Second Edition 14-16 Many light rail systems in Europe have specially equipped rail vehicles for performing preventative maintenance rail grinding. These cars are often older high-floor articulated vehicles that are no longer being used for passenger service. Read the entire page →
From page 680... ... LRT Track and Trackway Maintenance 14-17 Designers should carefully consider whether particular trackway environments might not be suitable for some products (such as a particular rail clip design) due to environmental conditions, loadings, or both. Read the entire page →
From page 681... ... Track Design Handbook for Light Rail Transit, Second Edition 14-18 14.6.4.5 Repair Cracked and Spalling Concrete Cracks happen, and, as noted for embedded track, they should be sealed so no water enters the interior of the concrete. If this occurs, then water may begin to rust the reinforcing steel; more importantly, this gives a path of least resistance for the stray current. Read the entire page →
From page 682... ... LRT Track and Trackway Maintenance 14-19 every fastener, and torque the hold-down bolts to the correct torque. While the fastener is not there, it is wise to inspect the concrete under the fastener to determine what caused the fastener to fail. Read the entire page →
From page 683... ... Track Design Handbook for Light Rail Transit, Second Edition 14-20 Many rail transit maintenance organizations, particularly on smaller systems, will not have the proper equipment and trained personnel necessary to correctly and efficiently perform out-of-face replacement of CWR. In such cases, it may be an activity best assigned to a qualified track contractor. Read the entire page →
From page 684... ... LRT Track and Trackway Maintenance 14-21 14.6.5.3 Repair Deflector Ramps at Crossings Every crossing should have deflector ramps that prevent dragging debris from abruptly getting caught on a sharp edge and causing damage. These ramps should be repaired immediately if damage occurs. Read the entire page →
From page 685... ... Track Design Handbook for Light Rail Transit, Second Edition 14-22 signals and must not interfere with track inspection or maintenance. There are professional services that can be contracted in order to keep vegetation from becoming a defect. Read the entire page →
From page 686... ... Abbreviations and acronyms used without definitions in TRB publications: AAAE American Association of Airport Executives AASHO American Association of State Highway Officials AASHTO American Association of State Highway and Transportation Officials ACI–NA Airports Council International–North America ACRP Airport Cooperative Research Program ADA Americans with Disabilities Act APTA American Public Transportation Association ASCE American Society of Civil Engineers ASME American Society of Mechanical Engineers ASTM American Society for Testing and Materials ATA American Trucking Associations CTAA Community Transportation Association of America CTBSSP Commercial Truck and Bus Safety Synthesis Program DHS Department of Homeland Security DOE Department of Energy EPA Environmental Protection Agency FAA Federal Aviation Administration FHWA Federal Highway Administration FMCSA Federal Motor Carrier Safety Administration FRA Federal Railroad Administration FTA Federal Transit Administration HMCRP Hazardous Materials Cooperative Research Program IEEE Institute of Electrical and Electronics Engineers ISTEA Intermodal Surface Transportation Efficiency Act of 1991 ITE Institute of Transportation Engineers NASA National Aeronautics and Space Administration NASAO National Association of State Aviation Officials NCFRP National Cooperative Freight Research Program NCHRP National Cooperative Highway Research Program NHTSA National Highway Traffic Safety Administration NTSB National Transportation Safety Board PHMSA Pipeline and Hazardous Materials Safety Administration RITA Research and Innovative Technology Administration SAE Society of Automotive Engineers SAFETEA-LU Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users (2005) TCRP Transit Cooperative Research Program TEA-21 Transportation Equity Act for the 21st Century (1998) Read the entire page →

From page 662...

... 14-i Chapter 14 -- LRT Track and Trackway Maintenance Table of Contents 14.1 PURPOSE 14-1 14.2 TRACKWORK STANDARDS 14-1 14.2.1 Track Construction Standards 14-1 14.2.2 Track Maintenance Standards 14-1 14.2.3 Track Safety Standards 14-2 14.3 ACCEPTANCE 14-3 14.4 WORKING SAFELY ON THE RAILWAY 14-3 14.4.1 Track Protection 14-4 14.4.2 Flag Persons 14-4 14.4.3 FRA 214 Regulations (If Applicable) 14-4 14.4.4 Risk Analysis 14-5 14.4.5 Preparatory Work 14-5 14.4.6 Profile of a Safe Person 14-5 14.5 INSPECTING THE SYSTEM 14-5 14.5.1 How Often?