Tire noise reduction effect of twin-layered drainage asphalt pavement

摘要

In this research, three different drainage asphalt pavement sections, which consisted of twin-layered drainage asphalt pavement, normal drainage asphalt pavement with 20% and 25% air voids, were constructed and surface characteristics and tire noise were surveyed in purpose of confirming the tire noise reduction effect of twin-layered drainage asphalt pavement. Investigation of surface skid-resistance and field permeability was performed prior to construction and 2 years after construction. As a whole skid resistance at each drainage pavement increased at 13 months after construction; however, it decreased at 22 months. The field permeability at 22 months after construction decreases in each drainage pavement. Especially the drainage pavement with 20% air voids showed remarkable reduction of field permeability and had large dispersion. Regarding the tire noise at twin-layered drainage asphalt pavement, it showed proportional increase between tire noise and skid resistance. The relation between field permeability of twin-layered drainage asphalt pavement, that of drainage pavement with 25% air voids and tire noise showed, that if the permeability decreased, then the tire noise would increase. With respect to the normal drainage asphalt pavement with 20% and 25% air voids, the tire noise at two years after construction was almost the same sound pressure level as before construction. On the other hand, the tire noise of twin-layered drainage asphalt pavement was 4dB (A) lower than before construction. Therefore, it can be said that twin-layered drainage asphalt pavement is more effective than conventional drainage asphalt pavement for reducing tire noise.