Tyre-road Interaction: a holistic approach to noise and rolling resistance

Sammanfattning: Energy dissipation, fuel consumption, real-estate property prices and health issues are some of the aspects related to the tyre/pavement interaction and its functional properties of rolling resistance and noise. The first two aspects are affected by the tyre/road interaction as energy is dissipated mostly by hysteretic losses as the tyre is subjected to dynamic deformations when contacting the pavement surface. The other effect of this contact system that is analysed in this thesis is noise. Excessive noise exposure leads to a decrease in real-estate property values and even health issues such as increased blood pressure, sleep disturbance, cognitive impairment in children, among others.To mitigate such issues, a good understanding of the underlying causes is crucial and therefore a holistic approach was used to analyse the contact interaction in a more comprehensive way, encompassing the pavement, tyre, environmental and contact media (contaminations). Both noise and rolling resistance were analysed after subjecting the contact system to controlled interventions in one variable while maintaining the other variables constant and then comparing to a reference condition. In the first part of the investigative work, different tyres were tested while maintaining the pavement, environment and contact media constant, allowing an evaluation of the impact of winter tyres on noise and rolling resistance. In the second part, an intervention in the pavement was applied while maintaining the other variables constant. allowing an evaluation of the impact of surface grinding on noise and rolling resistance.The first part quantified how noisier studded tyres are in comparison to non-studded tyres, yet no substantial difference in rolling resistance was found. The second part revealed the potential of the horizontal grinding to reduce noise and rolling resistance, having a limitation, on the duration of such effects, especially for Swedish roads where studded tyres are used.