It is known that different weather conditions require a specific design to take into account the main mechanisms acting between the tire tread block and the road surface. When developing all-season tires, additional research is necessary to find the best solution considering various road conditions. This paper analyzes the influence of the inclination angle of tire tread blocks and the tire tread blocks siping design on different surfaces on the friction forces in lateral and longitudinal directions. The tests were conducted on the hybrid test rig Realistic Pattern Testing in Lab at the Institute for Dynamics and Vibration Research of the Leibniz University of Hanover with different single tread blocks. Tire tread blocks with different numbers of sipes were rotated with an angle between 0° to 90° in 15° increments. To simulate different road conditions, artificially produced ice and snow tracks and real road wet and dry asphalt were used. For a better understanding of the mechanisms, high-speed images of the same samples sliding over a wet glass track were taken from below.
On the one hand, the measurement results and videos help to understand the influence of the inclination angle of a tread block sample on the friction process and show the different friction mechanisms on different surfaces and resulting forces in the two directions. On the other hand, the results show clear favorites for optimizing performance on individual surfaces.