Drive on it every day, and you probably take asphalt pavement for granted. You know it’s there, under your wheels, but what is it really made of? Asphalt pavement is a composite material of three parts: aggregate, binder, and filler.
Asphalt is a popular construction material. In fact, in the United States, asphalt paving, roofing, and saturated material production are anticipated to generate approximately $26.3 billion in revenue by 2024.
So, without further ado, let our construction experts at The Pavement Group fill you in on the science of asphalt pavement.
The Recipe: Asphalt Pavement
The first ingredient in asphalt pavement is aggregate. Aggregate refers to any particulate material. It can include sand, gravel, crushed stone, slag, and recycled concrete.
Next up is the binder. The binder binds the aggregate together and gives the asphalt its flexibility and strength. The most commonly used binder in pavement construction is a bitumen. Bitumen is a sticky, black, highly viscous liquid or semi-solid form of petroleum.
Last but not least is filler. Filler helps to fill any voids in the asphalt mixture and gives it an even surface texture. It also makes the pavement more durable by increasing its resistance to fatigue cracking and reducing its susceptibility to raveling.
What is the Layering Process of Asphalt Pavement?
Asphalt pavement is typically composed of five layers: the subgrade, subbase, base, binder, and surface course.
The subgrade is the layer of native soil or prepared material on which the other layers are placed.
The subbase is the layer of aggregate material that lies on top of the subgrade and provides additional support.
The base is the next layer up and consists of a more robust aggregate material that helps to distribute loads evenly across the pavement.
On top of the base is the binder, which, as we mentioned before, binds everything together and gives asphalt its flexibility and strength.
Finally, the surface course consists of a mixture of fine and coarse aggregate that provides a smooth, durable driving surface.
Coats, Compaction and Sealcoating:
Once all layers have been placed, they need to be compacted. This is done using a heavy roller that applies pressure to the pavement, densifying it and strengthening it.
After compaction, a thin coat of asphalt may be applied to the surface to provide an extra layer of protection against weathering and wear.
Sealcoating is another form of pavement maintenance performed on asphalt to extend its lifespan. This process involves applying a sealant to the pavement’s surface to fill in any cracks and prevent water from seeping in and causing damage.
So, there’s what this solid and durable pavement is made of! The next time you bike, skate or drive over asphalt, you can rest assured that it can handle the weight and wear. And remember, if you’re in the market for a new driveway or parking lot, The Pavement Group in West Palm Beach, FL, can help.
Get a free pavement quote now and see how much money you could save on your next project!