by Jeff Tuzik The L/V ratio is a ubiquitous measurement in the world of wheel/rail interaction. It is typically combined with the Nadal limit, functioning as shorthand for wheel climb derailment risk for a given set of conditions. But the L/V ratio and the various formulae used to set risk …
by Jeff Tuzik A lot of derailments happen at switches and turnouts. Many are low-speed, low-energy derailments that happen in yards and sidings. But they’re still costly and disruptive. Evaluating and optimizing wheel/rail contact conditions at these locations is different than it is on open track. It requires specific tools, …
by Jeff Tuzik Rail transit systems collect a lot of data. This is data collected from many sources—wheels, rail, track, and vehicles—and from many types of measurement devices. Some of the data must be collected per regulatory requirements, but much of it is collected because it’s valuable. Transit systems use …
by Jeff Tuzik What do 30 years of advances in wheel/rail interaction look like? Thirty years ago, the field of wheel/rail and vehicle/track interaction was largely unknown outside a coterie of specialists and researchers. Railroads operated within confined departmental siloes with vehicles on one side of the ledger, track on …
by Jeff Tuzik Track condition is about more than rails and ties. It includes everything below the rail and ties, too. Track components, ballast, and subgrade are all part of the package; they all affect overall track condition. And, as Brazil’s MRS Logistica’s track renewal programs have shown, improving track …
by Jeff Tuzik The benefits of friction management are well known and often touted. But one benefit in particular—fuel savings—receives far less attention than the others. But as railroads race to meet greenhouse gas reduction targets and ultimately net-zero goals that they have set for themselves, fuel savings have become …
by Brad Kerchof This article originally appeared in the September 2025 issue of Railway Track and Structures. It is reprinted here at their courtesy. Do you have experience arguing about derailment causes with another department? If so, chances are you have negotiated the cause of a switch-point wheel-climb derailment. The …
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 Jeff Tuzik Rail grinding is typically the go-to approach to addressing rail-related issues like corrugation, RCF, profile degradation, and a slew of others. It works. And on transit (and other closed-loop) systems, rail grinding can also be used to address wheel-related issues, as well. Greater Cleveland Rail Transit Authority’s …
by Jeff Tuzik A well optimized wheel/rail interface is a quiet wheel/rail interface. In the rail transit environment, there are many technologies and strategies to reduce wheel/rail-generated noise, and they tend to focus on reducing rail roughness. Standard rail grinding, acoustic rail grinding, rail milling, and specialized acoustic grinding machines …
by Jeff Tuzik Some information in this article has been updated since the original publication date. Internal rail flaws and defects are an unfortunate but unavoidable part of railroading. All railroads have them. All railroads have to repair them. Defect remediation, which involves cutting out the affected rail and replacing …
by Jeff Tuzik In the railroad industry, friction management takes many forms. Managing friction through the application of lubrication and friction modifier products is a key component of maintaining an optimized wheel/rail interface. North American railroads typically use some combination of gage-face lubrication and top-of-rail (TOR) friction modifiers on various …
by Jeff Tuzik The L/V ratio is a ubiquitous measurement in the world of wheel/rail interaction. It is typically combined with the …
by Jeff Tuzik A lot of derailments happen at switches and turnouts. Many are low-speed, low-energy derailments that happen in yards and …
by Jeff Tuzik Rail transit systems collect a lot of data. This is data collected from many sources—wheels, rail, track, and vehicles—and …
by Jeff Tuzik What do 30 years of advances in wheel/rail interaction look like? Thirty years ago, the field of wheel/rail and …
by Jeff Tuzik Track condition is about more than rails and ties. It includes everything below the rail and ties, too. Track …
by Jeff Tuzik The benefits of friction management are well known and often touted. But one benefit in particular—fuel savings—receives far less …
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 …
by Brad Kerchof This article originally appeared in the September 2025 issue of Railway Track and Structures. It is reprinted here at …