Q. What is Hot-Mix Asphalt (HMA)?
A. HMA is a combination of approximately 94% stone, sand or gravel bound together with approximately 6% asphalt cement, a product of crude oil. The asphalt cement is heated to approximately 340° F and blended with the stone in an asphalt plant. The hot-mix asphalt is loaded into trucks, hauled to the job, dumped into the asphalt paver, and laid onto the rock base or existing pavement in thin layers (2”-3”) or “lifts”. The asphalt cement gives the HMA the flexible nature to the pavement while the use of multiple lifts of asphalt increases the strength of the pavement and creates the term “perpetual pavement.”
Q. What is a Perpetual Pavement?
A. Perpetual Pavement is the term for thick, full-depth asphalt pavements that are constructed to last indefinitely. This sustainable pavement is built with thick base courses that are extremely flexible, a strong load-bearing intermediate course is placed over the base course, and followed by a two-three inch wearing course. This wearing course is milled off every 18-20 years, and recycled into a new wearing course. The intermediate and base courses remain strong and viable without ever needing to be totally reconstructed.
Q. What are the benefits of asphalt over other pavements?
A. Asphalt pavements are smooth, durable and long-lasting. They are safe, environmentally-friendly, cost-effective, and fast to construct. They can be built to be sustainable and perpetual.
Q. How are asphalt pavements more environmentally friendly than other pavements?
A. Asphalt pavements are the green pavement. In addition to all the other benefits of asphalt, asphalt pavements are 100% recyclable. In fact, with over 800 million tons being recycled each year, it is America’s #1 recycled product. With the addition of warm-mix asphalt, porous pavements, recycled shingles, and recycled rubber being added to the benefit side of asphalt, no other pavement come close to green asphalt. (Link to environmental advantages page.)