Contents October 2012 Volume 82, Number 10 18 ROADSCIENCE The Chemistry of Pavement Forensics
Our seven-part series on The Chemistry of Road Building Materials con- cludes with a look at road failure analysis; including, how steel corrosion occurs in reinforced concrete pavements; how the bonds of liquid asphalt to aggregate deteriorate and break over time; and the science behind portland cement concrete alkali-silica reactivity and sulfate attack. We also investigate the new generation of nondestructive pavement analysis tools.
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HIGHWAY CONTRACTOR Sub-Bases
A collection of some key research papers presented at the American Society of Civil Engineers' 2012 GeoCongress: glass in sub bases; triaxial geogrids; coal ash's value in bases; and subgrade stiffness and LTPP.
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APPLICATIONS & INNOVATIONS Wheeled or tracked?
It's a fairly common question. Which piece of equipment is bet- ter? The dominant answer is that the wheels or tracks choice largely depends on the job; but that doesn't mean that the deci- sion is simple.
COLUMNS & DEPARTMENTS 3 Lattatudes
40 Kirk Landers BetterRoadsDigital.com www.facebook.com/betterroadsmagazine Facebook www.Twitter.com,@BetterRoads Twitter
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AMERICAN CONCRETE PAVEMENT ASSOCIATION
PRODUCTS & SERVICE 36 Marketplace 39 Advertiser Index
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WEB EXCLUSIVES AND DIGITAL SPECIALS Just go to our website and click on "Web Exclusives" and "Contributed Case Histories." Here's what to look for in October:
1. Oldcastle Precast creates a special precast drainage concrete pipe for Philadelphia's Interstate 95 – Revive Project, a long-term, multi-phase infrastructure initiative to improve and rebuild 51 miles of I-95.
2. A township solves its salt storage problem. The DPW in the Township of Wayne, N.J., was storing its road salt on an asphalt pad under a large tarp. That's not only inconvenient, it can be hazardous. See what they did.
3. Web exclusive: Will tough regulations affect construction equipment resale? What will the Tier 4 fi nal regulations mean for the used construction equipment market? Special coverage from the Associated Equipment Distributors Executive Forum.
Solutions: Readers helping readers Got a problem? Email executive editor Tina Barbaccia a detailed description and we may post it on our website's new Solutions section so that experienced readers can share an answer. And if you have solved a challenging situation, let us know that too.
Better Roads October 2012 1
SPECIAL FEATURE Concrete Roads
Working with the American Concrete Pavement Association, we examine two subjects high on the must-read list for engineers today: Very thin concrete over- lays and roller-compacted concrete. Both are heading into new territory.
