Tire-pavement friction is a key component in road safety. Adhesion and hysteresis are the two main mechanisms that affect the friction between rubber tires and pavements. This study experimentally examined the relationship between rubber-pavement adhesion and friction. The adhesive bond energy between rubber and pavement surfaces was calculated by measuring the surface energy components of rubber and aggregates. The friction was measured in the laboratory using a dynamic friction tester. The results revealed that there is a fair correlation between the adhesive bond energy and measured coefficient of friction. A rubber-pavement system with higher adhesion provided higher friction at low speed. In addition, the results demonstrated that there is a strong correlation between rubber-pavement friction and rubber properties. Softer rubber provided higher friction and vice versa. The results of this study provide an experimental verification of the relationship between adhesion and pavement surface friction. The adhesive bond energy and rubber rheological properties could be incorporated in computational models to study tire-pavement friction in different conditions (e.g., speed and temperature).

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Pavement friction measurements are collected and used to assess the functional characteristics of pavements to ensure an adequate level of friction. There are several factors that affect pavement friction including the properties of the tire rubber materials and pavement surface texture characteristics. This study utilized the close-range photogrammetry (CRP) technique to measure the pavement macrotexture and microtexture. Texture parameters were calculated from the collected and analyzed images of the pavement surface. The results of the CRP texture measurements were compared with typical measurement methods. The CRP texture measurements had excellent correlation with the measurement methods used in this study; however, the CRP offers a simple and accurate, yet inexpensive, alternative to the current methods used to measure surface macrotexture and microtexture. In addition, the CRP texture parameters were incorporated in the Persson friction model to predict skid friction as a function of rubber properties. The results demonstrated an excellent correlation between measured and predicted friction. This study greatly simplified the texture parameter calculations needed in the Persson friction model with good accuracy.

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Highway traffic noise is a major environmental issue all over the world. This is particularly annoying to residents who live nearby major transportation corridors. Noise pollution adversely affects the quality of their life. It also causes sleep disturbance and anxiety. The most commonly used noise abatement technique is the use of noise barrier walls, which is costly and not always effective. Reducing the tire–pavement noise at the source is a viable alternative to cut down the noise level. This study examined the use of an impedance tube to measure the acoustic absorption of asphalt mixtures in the laboratory. The effect of various parameters on the acoustic absorption was investigated including aggregate gradation, aggregate type, binder type, percent air voids, and specimen thickness. In addition, factors that could affect the acoustical performance of asphalt mixtures after pavement construction were also investigated including air void structure, surface texture, temperature, and surface conditions. Percent air voids and layer thickness were found to have a significant influence on the acoustic absorption of asphalt mixtures. An analytical model was proposed to estimate the acoustic absorption coefficient of asphalt mixtures during the design stage. A good correlation was found between predicted and measured absorption coefficients in the laboratory. In addition, a double-layer system of asphalt mixtures was found to be effective in providing improved acoustical performance that overcomes the issues associated with the use of open-graded friction course as a wearing surface.