Citation

Brock E. Am. City Cty. 2006; 121(8): 2p.

Copyright

(Copyright © 2006, Penton Media)

DOI

unavailable

PMID

unavailable

Abstract

This article briefly describes some of the new paving materials and methods being used in asphalt and concrete to meet the ever-increasing demand for new road construction. The author discusses Stone Matrix asphalt (SMA), which is particularly valued for its durability and resistance to ruts, and rubberized asphalt, which incorporates pieces of recycled tire rubber that absorb sound and reduce surface damage caused by extreme heat and cold. The author also discusses perpetual pavement, which involves laying different types of asphalt to strengthen road surfaces. This reduces stress on the bottom layers, so only the top 2 or 3 inches need to be maintained. Another new pavement surface is warm-mix asphalt, a technique in which asphalt is mixed and poured at temperatures 50 to 100 degrees lower than typical hot-mix asphalt. The warm-mix technique releases fewer greenhouse gases and may extend the road construction season into cooler months. A final section brings readers up to date on concrete paving advances, including stringless technology (which uses a global positioning system to guide a slipform paver when it is laying a new road), dowel bars in the concrete, fast-track paving, and ultra-thin whitetopping techniques (the use of a thin overlay of concrete to patch an asphalt road).