The American Concrete Pavement Association (ACPA) introduced an online calculator that helps agencies, planning organizations, road builders, and contractors calculate estimated fuel and cost savings associated with building with concrete pavement versus asphalt.
The ACPA Green Streets Calculator (www.pavements4life.com/greenstreets) illustrates that concrete roads deflect less under loading, allowing trucks to get better fuel mileage; and concrete uses less fuel to construct than asphalt roads.
The online calculator accounts for highway/roadway design including road length, total road width, concrete thickness, comparable asphalt thickness, traffic, and fuel costs. Then the utility determines the minimum, average, and maximum impact of using concrete versus asphalt in relation to fuel usage and environmental impact. Visit www.pavements4life.com/greenstreets to try out the online calculator.
Material strengthens bridge design
The 35-foot-long Neal Bridge on Route 11, in Pittsfield, Maine, is the first to use a light, durable fabric to form the bridge arches that support the span. Developed at the University of Maine and dubbed “bridge in a backpack” because it transports inside duffel bags, the material can be installed in a matter of days, instead of the typical weeks construction can take. The process is believed to be a way to cut costs and lengthen the life expectancy of the bridge.
Made of composite materials, often a blend of carbon or glass fibers, the 23 fabric arches were assembled by university workers, cut into a pattern, and coated with a resin to retain their shape. Then they were taken to the site, put into place, and filled with concrete. Afterward, a lightweight deck was bolted to the top of the arches.
Much of the onsite preparation work was eliminated with this construction method, reducing hauling heavy beams. Visit www2.umaine.edu/aewc.
LaHood claims stimulus success
Transportation Secretary Ray LaHood says his agency has committed nearly $9 billion in stimulus money to states and territories. He informed the House Transportation and Infrastructure Committee that he thinks the money already has been an enormous success. The committee reported that as of the end of March, work had begun on 263 highway and transit projects in 30 states, thus putting about 1250 workers back on the job.
DOTs see rise in concrete's share
DOT staff in more than 50% of the states expect concrete's share of paving to increase during the next five years, according to a recent research study by the Portland Cement Association. Respondents cited concrete's life-cycle cost advantages and lower maintenance requirements as reasons for this increase. Fifty-four percent of states considered life-cycle cost an important factor in this rise. Additionally, concrete pavements were lauded for their performance on high traffic roadways, with 30% of the survey's response saying this reason would influence them to select concrete over asphalt.
The surveyed also measured the impact of sustainability issues on pavement choice. Although the majority of response considered sustainability to have only a minor impact on material selection, 50% of state DOTs see this influence increasing in the next five years.
The survey was completed in 2008 by employees from all 50 state DOTs. For more information, visit www.cement.org.
Hybrid composite bridge wins acclaim
The new High Road Bridge, over Long Run Creek in Lockport Township, Ill., recently received a national engineering award from the American Council of Engineering Companies.
The hybrid-composite beam bridge consists of three main subcomponents: an FRP shell, compression reinforcement, and tension reinforcement. The compression reinforcement is comprised of pumped concrete in an arch conduit within the beam shell. High-strenth steel strands run along the bottom, as the tension reinforcement. Visit www.acec.org.