Wet ice friction of conventional M+S tyres and of a retreaded M+S tyre with hard granules in thread rubber

Henrik Åström

The investiga tion comprised tests with a total of eight passenger car tyres classified M+S, without studs. One of the tyres had a special hard aggregate added to the rubber compound to increase the grip on ice. The tests were carried out in the VTI tyre testing facility on smooth wet ice at a speed of 30 km/h. Both braking tests and steering tests were performed. Results from the braking tests was presented as maximum braking friction, braking friction at 13 % longitudinal slip and friction with a locked wheel. The steering tests were presented as maximum lateral friction and friction at 3, 5, 10 and 20 degree side slip angle. 20 degree side slip angle represents conditions of skidding of the whole vehicle or excessive steering angle when entering a curve.



ICTTP 2020

ICTTP, International Conference on Traffic and Transport Psychology, is held in Gothenburg, Sweden.



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