One interesting part of the asphalt process that you might not be aware of happens before any asphalt is laid. It’s called asphalt milling.

What is asphalt milling?

Milling is the process of removing the top layer of asphalt to a specified and even depth without disturbing the underlying subbase. This allows new asphalt to be laid down without increasing the height of the road and saves you time if the subbase doesn't need to be fixed. Thanks to the milling process curbs, drainage and other existing structures remain undisturbed.

You may already be aware that the asphalt being laid down for new roads and patching older roads is largely made up of recycled material.  In fact, asphalt is one of America’s most recycled materials.  You may also be aware that, in some cases, the recycled material comes from roofing shingles as well as roads. 

Using RAS in Asphalt Mixtures

The use of recycled asphalt shingles, or RAS, has been fairly limited in the past, though, mostly because roofing materials contain a lot of extra material besides the asphalt itself.  For example, roofing shingles may have nails, plastic, fiberboard, paper, cellophane, and wood.  This makes the recycling process much more challenging. 

Additionally, local and state governments have been waiting on additional studies to be done regarding whether asphalt-using RAS is as reliable as asphalt that does not use it. These studies are increasingly showing that asphalt that uses RAS is as reliable and durable as more standard asphalt mixes, provided they are properly mixed.  Therefore, the use of RAS mixtures is on the rise.

Asphalt might not be the first thing you think of as something that can be environmentally friendly. But asphalt is just that. 

Businesses are always looking for ways to save money.  The best way for asphalt companies to save money is to recycle asphalt shingles and asphalt pavement. In 2019 alone, 24 million barrels of asphalt binder was conserved because of the recycling of asphalt shingles and asphalt pavement. (NAPA, 2020)

The asphalt industry is full of events that bring in new perspectives and help expand the knowledge base of those in the asphalt paving industry. The World of Asphalt Show and Conference 2012, March 13-15, in Charlotte, North Carolina, provides over 40 educational sessions and many opportunities to talk to industry experts and view over 300 exhibitors. Here’s a brief overview of what the conference has to offer.