by Jeff Tuzik Vehicle stability is of paramount concern in the rail transit environment. It affects safety, ride quality, and wear and damage on the track, wheels, trucks, and suspension. In turn, stability is largely defined by the interplay of track characteristics, wheel and rail profiles, and truck and suspension …
by Jeff Tuzik (This article was previously published in the December 2025 issue of Mass Transit) One of the most vexing, and increasingly common rail defects that rail transit agencies contend with is the squat-type defect (stud). Addressing studs has been challenging in that they are not fully understood, and, …
By Jeff Tuzik Friction modifiers—whether gage-face lubricants (greases) or top-of-rail (TOR) friction modifiers (FM)—are a well-established, and indeed, a common part of the wheel/rail optimization toolkit. In the railroader’s mind, these technologies tend to be associated with wayside application equipment and installations, but vehicle-mounted wheel-flange lubricators and wheel-tread friction modifiers …
by Jeff Tuzik On passenger rail systems, disruption is never good. With tight headways and packed cars, a small disruption of service doesn’t stay small for long. Major disruptions, such as those that require taking a track out of service for repair, are worse yet. On São Paulo’s Metropolitan Train …
by Bob Tuzik This article was originally published in Mass Transit (February 2022). SkyTrain, Vancouver’s iconic rail transit system, is a system in motion. Since the opening of the original Expo Line, named and timed to coincide with Expo 86, SkyTrain, which moves more than 115 million commuters per year pre-covid, …
by Bob Tuzik This article was originally published in Mass Transit (June 2023). Challenges abound in the design, construction, maintenance, and operation of light rail lines in urban areas. Chief among them is controlling track- and vehicle-born noise, an important part of maintaining the support of an agency’s various stakeholders, …
In 2022, Wiener Linien faced severe wheel wear issues on line U6 after a rail renewal project. The complex problem stemmed from poor wheel/rail dynamics, necessitating collaborative efforts for analysis and remediation. New wheel and rail profiles, designed to optimize contact conditions, are expected to significantly reduce wear and damage.
by Jeff Tuzik Stuart Grassie, Principal, Rail Measurement Ltd and Stuart Grassie Engineering Ltd, is the recipient of the 2024 Worth Award. The award, presented by Wheel Rail Seminars at the annual Wheel/Rail Interaction conference in May, is named for Art Worth, who was Manager of Standards and retired as …