Design, fabrication, and laboratory performance evaluation of polyurethane poroelastic road surfaces (PERS) mixtures

Abstract

Polyurethane poroelastic road surfaces (PERS) demonstrate convincing noise reduction capabilities but face challenges from the lack of corresponding design methods and mixture rebound caused by incorporating high-content rubber particles. This study aims to optimize the material composition and mixture design of PERS using the Coarse Aggregate Void-Filling (CAVF) method, focusing on the effects of rubber particle content, rubber particle size, and stone aggregate size on the performance and noise reduction characteristics of PERS. A total of 24 single-particle-size polyurethane porous elastic mixtures were designed with varying rubber particle contents (15–30 wt%), rubber particle sizes (2–3 mm, 3–4 mm, 4–5 mm), and stone aggregate sizes (4.75–7.5 mm, 7.5–9.5 mm). The initial curing characteristics of polyurethane were evaluated using a Brookfield viscometer and extrusion quality tests. The optimal molding time window was determined through Marshall specimen height tests and 15℃ splitting tests. The road performance and noise reduction properties of PERS were assessed using Cantabro loss test, high-temperature rutting test, low-temperature bending test, Marshall stability tests, freeze-thaw splitting tests and tire vertical drop test. The optimal molding time window for PERS was found to be between 40 and 50 min after polyurethane curing, balancing mechanical performance and minimizing rebound. PERS exhibited excellent raveling resistance performance (weight loss < 8 %), outstanding rutting resistance (rut depths < 1 mm) and notable low-temperature flexibility (bending strain >7927.5 με). Marshall residual stability and freeze-thaw splitting strength decreased with increasing rubber particle size, increased with larger aggregate sizes, and decreased with higher rubber content. Compared to AC13 mixtures, PERS showed a significant increase in damping ratio (up to 242 %) and noise reduction (up to 10.7 dB(A)). This study provides new insights into the material composition and mixture design of PERS, serving as useful references for the promotion and application of PERS pavement.