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Issue 2 • Volume 3 • April 10
AWARDS
Northwest Division's Inland Asphalt Company Wins 2009 ARRA
Recycling Award
As a prime contractor during a 13-mile cold-in-place
recycling* (CIR) project on US Highway 2 near Newport,
Wash., Inland Asphalt Company relied on the Internet
to track cloud movement and temperature fluctuations
on a real-time basis to ensure that temperatures would
reach at least 60 degrees Fahrenheit each work day.
In conjunction with the Washington State
Department of Transportation (WSDOT) and the
resurfacing subcontractor, Inland applied the CIR
process to this project and earned the Asphalt
Recycling and Reclaiming Association (ARRA)
recycling award from Roads & Bridges magazine.
The US 2 Junction with State Route 211 leading into
Newport had been under constant care for years. The
15-year-old, 13-mile stretch had received dozens of
pothole patches, the result of hot, humid summers
followed by equally intense conditions on the
opposite end of the thermometer during the winter.
The weather, combined with the passing presence
of heavyweight trucks, reduced the lifespan of the
typical pavement in the region to just 11 years. The
WSDOT pulled four more years out of S.R. 211, but
the extra beatings left cracks as deep as 4 inches.
"The section of road has a lot of truck and studded
tire traffic, so over the years, they have had some
problems with rutting, and our maintenance division
did a lot of patching with hot-mix asphalt (HMA)," John
Morris, assistant project engineer with WSDOT said.
"So there were different types of materials out there."
Due to the inconsistency in the pavement, Inland
Asphalt had to pull 12-inch cores every half mile in each
direction prior to the start of the CIR process so the
WSDOT could come up with two different mix designs.
After the CIR material was successfully placed,
crews had to wait about two weeks for the CIR
layer to cure prior to applying the 2-inch HMA layer.
Paving too early could have resulted in the moisture
creating tiny bubble pinholes.
Inland Asphalt was able to place a portable asphalt plant
right in the middle of the 13-mile project. "The material
was a good source," said Morris. "The crushing people
were really good and consistent, so you had a consistent
pile. The asphalt plant and loader operators were
experienced, so the material you were getting out in the
field and through our asphalt plant was very uniform."
WSDOT crews rode an International Ride Index (IRI)
van to check for smoothness. Before the project,
the IRI index was 139. When the job was complete it
was 68, resulting in a 51 percent improvement. The
WSDOT also checked for pavement grip and Inland
Asphalt received a rating of 3 on a 1 to 5 scale.
Wait times and the unpredictability of the weather
aside, the end result offered the same degree of
success for everybody. The use of CIR saved the
WSDOT more than $1.25 million, relieved motorists of
a stretch of highway that was well past its service life
and earned Inland Asphalt the recycling award.
Ken Gibson, Inland operations manager, noted,
"This was our largest CIR project to date. With good
planning by our people and the joint partnering of
the WSDOT and our subcontractors, this project has
given both quality and cost savings to the taxpayer."
"We start every job with the expectation that they
are going to turn out like this," Chad Simonson,
project engineer for WSDOT, said. "When you do
something that is out of the norm with cold recycle,
keep a fantastic relationship with the contractor
and have a job that is good enough to be an award
winner ... these jobs are the jobs you want and that
you pray for every day."
*CIR utilizes the existing asphalt roadway as a source
of materials that may be used to build a new base
layer. The surface is pulverized down to a specific
aggregate size, mixed with an asphalt emulsion,
and then laid down and compacted to the specified
density. After a curing period, the recycled material is
surfaced with a new asphalt wearing course.
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