Mechanical and Acoustic Properties Composition Design and Effects Analysis of Poroelastic Road Surface

Existing low-noise pavement has gradually lost its function with the development of urban road traffic. A poroelastic road surface (PERS), mainly composed of tire rubber granules, polyurethane, and aggregate, is considered to be the material with the most potential to construct future low-noise pavements. This study aims to optimize the material composition of PERS to improve the mechanical and acoustic properties further. The orthogonal experiments of three factors with three levels were designed to evaluate the effects of the composition design of PERS on rutting resistance, skid resistance, moisture resistance, and aging resistance. To ensure the acoustic properties, the selected initial composition was optimized through the tire free-drop test and transfer-function method. In this study, the Pearson correlation coefficient (r) was used to describe the correlations between the properties of PERS and material composition. It was concluded that skid and moisture resistance are largely influenced by polyurethane content. Meanwhile, the rubber content is significant for rutting resistance, aging resistance, and damping property. Acoustic experiments indicate that rubber particles show a significant effect on the sound absorption property. Results demonstrate that the optimal material composition of PERS is 5.5% polyurethane content, 10% rubber content, and 1.18 mm rubber particles, with a 60 mm thickness.