摘要: |
The level of noise generated by tire/pavement interaction of a pavement section changes over time. While the general consensus is that the noise level tends to increase as the pavement ages, more scientific investigation is necessary to better understand the process of acoustic aging of pavements. For more than a decade, independent studies by Caltrans and the Danish Road Institute (DRI-DK) have included monitoring of tire/pavement noise levels on selected pavements. Using data sets collected as part of those studies, a comprehensive analysis was conducted in this study to characterize the acoustic aging properties of different types of asphalt pavements. Pavement types considered in the analysis include dense-graded asphalt concrete (DGAC), open-graded asphalt concrete (OGAC), thinopen-graded asphalt layer, and porous asphalt concrete (PAC). This report presents the results of the data analysis in terms of the relative changes of tire/pavement noise over time for the respective pavements. It also describes the development of an acoustic aging model for asphalt pavements. The model predicts the increase in noise level as a function of pavement age, traffic volume, and pavement type, primarily for highways with speeds over 50 mph. |