Cement strengthens US 79

When severe alligator cracking reared its ugly head along a heavily trafficked US 79 near Jacksonville, state engineers faced a challenge. Drop offs along the narrow, hilly two-lane highway meant building detours would be impractical. "We had to keep traffic on it while we strengthened it," says Mark Sturrock, assistant area engineer, Jacksonville area office, Texas Dept. of Transportation. Engineers decided to recycle the roadway in-place. They tested lime and cement to determine which material worked best, says Sturrock. Full-depth recycling (FDR) with cement proved "the most efficient way to keep the road open and not double-handle the material," he says. In March 2002, crews from Madden Contracting Inc., Minden, La., began the $7.4-million contract to rebuild an 11-mile stretch of US 79 west of Jacksonville. Madden mixed the existing asphalt and base with more than 8,000 tons of cement, 4% cement by dry weight of the materials, into 333,864 sq. yd. of roadway to create a strong, long-lasting base. A five-inch asphalt surface topped the new road. "There really were no negatives but the tempo was fast. It kept us on our toes," says Ken Smith, the project's TxDOT inspector. Madden crews mixed in 260 tons of cement per day. "It's simpler than fooling with lime because you have to cut lime twice," adds Kirkland. Finished four months ahead of schedule, the project was deemed "a tremendous success," says Ken Smith, the state inspector overseeing the project. "With cement, you get a tremendous strength." The success of the FDR project encouraged engineers to design a second project for US 79, now underway east of Jacksonville. The 10-mile, $6.1-million project is slated for completion next summer.

©2005 Road Recycling Council
P.O. Box 17362 - Cambridge, MA 02141
phone: (857) 998-0119 fax: (617) 547-0042
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