Porous Asphalt (PA/OPA)
Noise reducing surface course preventing aquaplaning
The PA strives for a "mono aggregate framework" and thus retention of voids in the surface layer. The resulting cavity structure between the minerals is only partially filled with mortar and warrants permeability for water and air. Drainage of surface water effectively prevents the aquaplaning effect.
PA requires the installation of a waterproof sealing between the sub-construction and the porous surface layer as well as a sewage system beside the road.
The air discharging through the void structure reduces the production of rolling noise forced from the "air-pumping effect". Since the mortar phase is almost exclusively made of bitumen and filler, the separation of bitumen and stone aggregates is effectively prevented by the addition of CFF cellulose fibres.
The PA surface installation benefits the following traffic areas:
- noise reduction on motorways and interstates
- areas with increased aquaplaning danger (troughs, indentations, etc.)
Porous Asphalt should not be paved in traffic areas with a high dirt load. The void structure could clog with dirt particles and the desired drainage effect would be prevented (for more notes, cf. German bulletin for construction of porous asphalt surface layers M OPA 2013).
In case you have questions or require more detailed information on our CFF cellulose fibres (pellets, granules & loose fibres) in road construction we will be pleased to assist you.