Effects of asphalt pavement characteristics on traffic noise reduction in different frequencies

To evaluate the effects of asphalt pavement characteristics on traffic noise reduction in different frequencies, stone mastic asphalt with crumb rubber and porous asphalt concrete were prepared. Dynamic modulus test, air voids test, standing wave tube test, improved tire acceleration method, water submerged test and voids-clogging test were utilized. The results showed that the deformation characteristics of stone mastic asphalt have significant effects on the tire-pavement noise reduction in intermediate-frequency and high-frequency bands. Larger connected air voids of porous asphalt concrete could obtain better ability of noise reduction, especially in the low frequency band. Both the water submerged and voids-clogging have slight effects on the noise reduction of stone mastic asphalt, while having greater influences on porous asphalt concrete. Water submerged mainly increases the high-frequency band noise, and voids-clogging affects the noise at low-frequency and high-frequency bands. These findings provide significant guidance in the application and promotion of ecological low noise pavements.