 Noise reduction can be achieved by designing gap-graded asphalt mixtures (to visualise this think about rice crispy cakes) that allow the noise to dissipate within the voids of the material itself. Porous Asphalt (sometimes called drainage asphalt) has been successfully used in many countries to achieve noise and spray reduction. Most recently, use of dual layer porous asphalt has been used to achieve excellent noise reduction. In other countries gap-graded thin surfacings (eg. UK) have also been shown to reduce noise compared to conventional surfacing.
Most of these products involve the use of a polymer modified bitumen, and Shell have a history of providing custom binders (eg.Shell Cariphalte DA) that have been designed specifically for use in these gap-graded asphalts. >> Shell Cariphalte DA |
