Crews taking core samples of a test strip of foamed asphalt base on northbound U.S. 29.
The Maryland Department of Transportation's State Highway Administration (SHA) is using recycled materials on a road-widening project in Columbia, which is in Howard County. The new travel lane on U.S. 29 will include 2,600 tons (2,358 t) of recycled material.
A SHA spokesperson noted that the recycled material, “foamed asphalt,” is made of reclaimed asphalt pavement and cement. In general, foamed asphalt production involves injecting water into a special chamber that contains millings from other resurfacing projects, causing the asphalt to foam and bind together. This produces a useable material that is 10 to 15 times the original volume of the millings. The material is then mixed with Portland cement to create the final product. The recycled material will be used as a base course and will be the proper load-bearing strength after compaction.
“Using recycled materials in road building and maintenance supports practical design principles,” said SHA Acting Administrator Douglas Simmons. “The amount of material in this case is about half the volume of water in an Olympic-sized swimming pool. Using less new asphalt and wasting less from other projects is an environmental benefit.”
The project began in the spring of 2014, and is scheduled for completion (weather permitting) in the summer of 2016. The total cost is $32.7 million. It is located on Northbound U.S. 29 (Columbia Pike) between Seneca Drive and MD 175. It covers 3.1 mi. (4.98 km) in a location that sees approximately 77,000 vehicles per day.
The prime contractor is Allan Myers of Fallston (formerly American Infrastructure). The contractor contact is Paul Calvaresi. The SHA project engineer is Brian Pickens.
Nearly 3 mi. (4.8 km) of northbound U.S. 29 from Seneca Drive to MD 175 will be widened from two to three lanes. A sound wall also will be constructed along northbound U.S. 29 within the project limits, and the ramp from northbound U.S. 29 to eastbound MD 175 will be realigned to improve safety and sight distance.
SHA noted that the project will reduce congestion and improve safety by widening northbound U.S. 29 to match the southbound section. Currently, southbound U.S. 29 has three lanes, while northbound U.S. 29 only has two lanes. The northbound side experiences severe congestion, particularly during morning and evening rush hours.
Heavy spring and summer rain have been a factor in this project, according to Charlie Gischlar, SHA public information officer.
Some equipment used on the project includes pavers, rollers, cranes (for sound walls), front end loaders, excavators and dozers.
Subcontractors include Chesapeake Pile Driving Inc., Erosion Control and Landscape Services, J & M Sweeping, Long Fence, Mattiola Services LLC, McKinney Drilling Company Inc., Mohawk Bridge & Iron Inc., Native Terrain Restoration Services, Paul J. Rach Inc., and RNG Construction.