As the world’s population continues to rise, it brings with it an increase in the amount of traffic-related noise pollution. This fact is only amplified as housing developers are forced to build closer and closer to major highways. With this in mind, asphalt producers are striving to create a material that will limit noise pollution, while at the same time being sustainable. Here is some information on asphalt mixtures and their noise reducing qualities.
Freshly laid asphalt is one of the quietest road material available, however, as the asphalt ages, these qualities begin to dissipate. This has led asphalt producers to experiment with various mixtures to determine their noise reducing properties. There are three main types of asphalt mixtures:
When it comes to permeability, open-graded asphalt reigns supreme. With open-graded asphalt, water can easily flow through the surface of the material and this helps to prevent standing water from becoming an issue. This permeability also makes for a quieter surface, since the pores in the surface tend to absorb some of the noise created by vehicles on the surface. And while the porous surface is susceptible to clogging, thus reducing its noise absorption qualities, it remains an efficient way to decrease traffic noise levels.
As the name suggests, dense graded asphalt is more compacted than open-graded asphalt. On the other hand, since dense-graded asphalt uses smaller particles in its mixture than that of open-graded asphalt, it tends to hold similar noise reducing properties. In fact, research has suggested that this type of asphalt can lower noise levels by up to 8 decibels – a substantial decrease.
Unlike dense-graded asphalt, fine-graded asphalt tends to have a thin surface depth, which helps with road surface preservation. Not only this, but this ultra-thin bonded surface means that there is less contact between the surface of the road and the tires of the vehicles, and this goes a long way in reducing noise levels.
A Grade for All Scenarios
As more drivers take to the road, noise pollution levels will continue to increase. Thankfully, asphalt manufacturers are searching for ways to counter this ever-present issue. One way to ensure that noise levels remain low is by using porous asphalt, as it works well in absorbing noise pollution. In addition, dense-graded asphalt, which utilizes smaller particles than other types, can aid in lowering noise levels by up to 8 decibels. Lastly, asphalt that is of the fine-graded type can help decrease noise by limiting the contact between the tires and the surface of the road. By using these asphalt materials, producers are ensuring that noise levels are kept to a minimum.