2023 Rail Transit Session
Studs, Squats, and similar damage mechanisms
Advanced Rail Management
Plasser & Theurer
Squats are a well known rail defect that was first found on Japanese high-speed lines in the 1960s and subsequently developed into an often-found defect all over the world. After a decline in appearance in the 1980s, the defect massively reappeared in the 1990s. Research in Europe and Australia revealed that this re-emerging defect exhibited different characteristics compared to the pre-1980s Squats. This led to the introduction of new defect names like “Stud”, “Squat-like”, or “Squat-type” defect but the term “Squat” continues to be used for both the traditional and “new” defect due to the visual similarities. This presentation will highlight the research conducted in Europe and Australia since the 1990s and identify existing knowledge gaps as well as the various opinions (sometimes conflicting) from the scientific community on this defect. The group will present case studies on the appearance of these defects in North America, a more recent phenomenon, that includes investigation into the potential root causes, potential safety and ride quality implications, and attempts at remediation/prevention to help provide insight for other railroads if and when these defects appear on their systems.