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RT3 Surface Traction Measurement Technology

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Environmental Services

RT3 Surface Traction Measurement Technology is used to measure road friction conditions in real-time and provides invaluable insight during snow and ice events. By providing real-time data on surface traction during all types of winter weather, the RT3 enables MassDOT to more effectively evaluate and react to current roadway conditions. The RT3 also makes it possible to measure the effectiveness of deicing and anti-icing products, adjust application rates and eliminate over application while ensuring safe roads.

R T 3 auxiliary wheel

The RT3 uses an auxiliary wheel that attaches to a truck’s undercarriage or can be towed behind a vehicle. The friction testing wheel is set at a slight side angle, creating a force that is measured and converted into an electrical signal, which is then transmitted to a computer inside the cab.

R T 3 display screen

Friction readings are presented to the operator as colored lights on a display: green indicates safe driving conditions, yellow indicates roads where caution is needed, and red indicates dangerous areas that require immediate attention.

Friction data can provide a real-time picture of changing road surface conditions. Operators and supervisors can use the data to help determine when to start and stop treatment, to modulate the amount of chemical used, and to measure effectiveness of the treatment process. For example: When road friction drops below 70, cars won’t be able to stop short and will tend to skid a little when brakes are applied. And when the friction drops below 50, people are most likely to lose control of their cars. RT3 operators can look at sets of data (as shown below) and see what areas of roadway need to be addressed.

affectiveness of treatment process plotted graph
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