Rail Integrity Experience on the Washington Metro System

PDFResearch PaperJRC2016-5710Rail jointsRailheadRail (Railroads)Rolling contactDynamicsFracture mechanicsDefectsRailroad safetyWheel loadsTemperatureWashington Metropolitan AreaAmerican Society of Mechanical EngineersFrison, BenjaminJeong, David Y.Washington Metropolitan Area Transit AuthorityJohn A. Volpe National Transportation Systems Center (U.S.)AGR-SAFETY AND SECURITY-SAFETY AND SECURITYNTL-RAIL TRANSPORTATION-RAIL TRANSPORTATIONNTL-RAIL TRANSPORTATION-Rail SafetyNTL-PUBLIC TRANSPORTATION-PUBLIC TRANSPORTATIONNTL-PUBLIC TRANSPORTATION-Transit Safety and SecurityVolpe National Transportation Systems Center, Technical Reference CenterThe Washington Metropolitan Area Transit Authority (WMATA) provides passenger rail service to the nation\ue2\u20ac\u2122s capital. Although the rail system carries only passenger trains, the rail integrity issues that WMATA must manage are similar to those that freight railroads also face. These issues include occurrences of broken rail from internal rail head defects, detection of such defects, and repair of the rail to restore service. Another example is the development of damage on the running surface of the rail, called rolling contact fatigue (RCF). Such surface damage is known to adversely affect the detection of internal rail head defects beneath RCF conditions. While WMATA\ue2\u20ac\u2122s rail integrity issues may be similar to those that freight railroads also encounter, the management of such issues are different, which are also discussed in this paper.This paper describes the recent experience of broken rails on the WMATA rail system. In addition, results from engineering fracture mechanics analyses are presented to help understand how operational, environmental, design, and maintenance factors influence rail failure