Hot Mix Asphalt Technology - May/June 2011 - (Page 9)
Who Knew Asphalt Could Be So Green?
sphalt is a unique substance with exceptional attributes. It starts out as crude oil which is refined into asphalt cement, an organic substance with the ability to bind rocks together to make the best, longest-lasting pavements on the planet. Once constructed, asphalt pavements have mighty power to connect places and people with goods, services, activities, other places, and other people.
Even more exceptional is what happens when an asphalt road eventually needs renewal. A milling machine can be used to remove the top inch or two of the road. The millings are transported to an asphalt plant, where they are processed, heated, and mixed with virgin materials to make new pavement material. And the asphalt cement in that 20-or-more-yearold pavement is reactivated. One could say that it is transformed, but actually it is simply restored so that it acts the same as it did originally – it retains its power as a glue, binding the new pavement together just as well as it originally did. This renewal process can happen over and over again. At 20+ years, then at 40+ years, then at 60+ years, and at 80+ years …. on and on; you get the idea. And while asphalt cement is being born
again and again, the original road structure stays in place, doing its job, connecting people. Asphalt cement, an inimitable gift from the earth, is completely different from portland cement, which is manufactured in a destructive process. Where the two products are similar is that portland cement is also mixed with stone, sand, and gravel to make pavements. But when portland cement concrete pavements need rehabilitation, the cement cannot be reactivated, and the concrete chunks can be recycled as aggregate. It is rarely put back into portland cement concrete pavements or structures. As an asphalt professional, you already know all this – but you probably don’t think about it very often, and you may never have expressed these ideas to your neighbors or indeed to anyone outside the industry. Which gets me to my point. We who work within the industry need to step up our efforts to tell our story to people outside the industry. We who love asphalt need to educate others that this sticky black substance is actually one of the greenest materials known to man. That’s why NAPA created the new Web site at www.PaveGreen. com. PaveGreen is totally oriented to the general public. This makes it different from NAPA’s site at www.hotmix.org and the Asphalt Pavement Alliance’s site at www. AsphaltRoads.org, both of which provide information for everyone from sophisticated engineering professionals to contractors to the general public. PaveGreen is all
By Kim Snyder, NAPA Chairman
We who love asphalt need to educate others that this hot, black, sticky substance is actually one of the greenest materials known to man.
about the greenness of asphalt and all about serving the information needs of audiences including environmentalists, students, reporters, homemakers, and other members of our communities. Once you visit PaveGreen.com, I’m sure you will want to share the story of green asphalt with others. NAPA has a host of promotional materials to help you in that endeavor, from Web banners to bumper stickers to pens and notebooks. Contact Margaret Cervarich, NAPA’s Vice President for Marketing and Public Affairs, at email@example.com to obtain these tools. You can be proud of being part of the industry that reuses and recycles more than any other industry in the country. And you can be proud of helping NAPA showcase this HMAT amazingly green substance. Kim Snyder is the President of Eastern Industries Inc., Pennsylvania. He is also the 2011 Chairman of the National Asphalt Pavement Association.
Hot Mix Asphalt Technology – MAY/JUNE 2011 • 9
Table of Contents for the Digital Edition of Hot Mix Asphalt Technology - May/June 2011
Hot Mix Asphalt Technology - May/June 2011
Chairman’s Commentary: Who Knew Asphalt Could Be So Green?
Warm-Mix Asphalt: Best Practices
States Stride Ahead With Warm Mix
Roads to Rubble: De-Paving a Half-Century of Progress
NCAT Explains the AMP Tester
Tools for the Trade
Calendar of Events
Index of Advertisers/Advertisers.com
Hot Mix Asphalt Technology - May/June 2011