Asphalt
What is asphalt and its uses?
Americans prefer the term asphalt when referring to the sticky, black, viscous liquid form of petroleum, whereas the same substance is known throughout most the world as bitumen.
We can find most of the asphalt used in construction today in road construction.
What is asphalt made of?
It is a binder mixed with an aggregate creating asphalt cement that binds the stone, sand, and gravel, resulting in the pavement for our roads and highways. A small percentage of asphalt is used in waterproofing, sealing, and insulation products.
According to the National Asphalt Paving Association, the United States has approximately 3,500 asphalt plants that produce a total of about 400 million tons of asphalt pavement—a material worth over $30 billion.
What are the properties of asphalt?
However, the asphalt on our roads shouldn’t be thought of as just a simple binder for pavement. It’s much more complex than that. For example, we developed an asphalt mix tailored to resist extreme weather, be it bitterly cold winters, or warm, humid, seaside areas. In these conditions, the common problem is salt—whether naturally occurring in the environment as it does in coastal towns and cities, or purposely applied to deal with snow and ice.
There is also research being carried out to develop self-healing asphalts and even asphalt that can recharge electric vehicles or absorb pollution. But even without all these innovations, asphalt has benefits that extend beyond a smoother, safer drive.
According to the Environmental Protection Agency and the Federal Highway Administration, asphalt pavement is the United States’ number one recycled product.
They also say that reclaimed asphalt pavement (RAP) and recycled asphalt shingles (RAS) saves more than 60 million cubic yards of landfill space each year.
Asphalt pavements may also help projects qualify for LEED credits in part through using recycled materials, but also by incorporating porous asphalt pavements. The Environmental Protection Agency recognizes permeable pavements as a best management practice for stormwater management.