Acoustic aging of low-noise pavements in Hong Kong : regression modelling and mechanism investigation

Abstract

This study aims to model the acoustic aging behavior of low-noise pavements (LNPs) and investigate their acoustic aging mechanisms. Three LNPs commonly used in Hong Kong were selected: polymer-modified friction course (PMFC), polymer-modified stone mastic asphalt (PMSMA), and crumbed rubber-modified stone mastic asphalt (CRSMA). Acoustic aging mechanisms were analyzed by noise levels, noise spectra, and traffic- and climate-related data. Regression models were developed to predict acoustic aging behaviors. Key factors affecting the acoustic aging of LNPs were identified. Results indicated that PMFC6 generated the lowest initial TRN but experienced the fastest acoustic aging rate, while CRSMA6 demonstrated superior noise-reduction durability over 5 years, followed by PMSMA6. Lane positions and construction site locations had influences on acoustic aging rates. Both power function and logarithmic regression models could effectively describe the acoustic aging of PMFC and PMSMA pavements. Tire-road noise (TRN) was primarily influenced by road age, LNP type, and test speed.