CAM Asphalt Rehab 2K12_CAM BOOK 2012 4/27/12 4:36 PM Page 16
Written by: Brian Hoover
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California Asphalt Magazine • 2012 Asphalt Rehabilitation Issue
CAM Asphalt Rehab 2K12_CAM BOOK 2012 4/27/12 4:36 PM Page 17
Left: CCPR asphalt is urban friendly and cost effective.
Background: RX 500 machine loading into truck.
Right: At the recycling site, the RAP is crushed, screened,
and processed with an engineered emulsion in the
manufacturing of CCPR asphalt.
raditionally, the City of
Palm Desert has repaired
failing sections of asphalt
pavement with localized
repairs and a thin 1.5” – 2” hot mix
overlay. On some streets the City
used paving fabric. Although this
method kept roads drivable and costs
at bay for a period of time, it became
apparent that the 30 to 40 year old
street sections were deteriorating
faster, while the cost of hot mix
overlay had increased to approximately
$2.50/sq. ft. Many of the first
developments in the City of Palm Desert
were built in the 60’s and 70’s and
most of the residential neighborhood
streets were constructed with a
relatively thin layer of asphalt that was
paved directly over the native base.
The City of Palm Desert’s pavement
represents one of its single largest
investments and it was now time for a
more affordable and environmentally
sustainable solution. After weighing
the costs of several conventional and
alternative methods, the City decided
to go with Cold Central Plant Recycling
(CCPR). General contractor, Matich
Corporation, took on the project with
the help of subcontractors, Pavement
Recycling Systems, who provided all
of the removal and asphalt recycling,
and Western Emulsions, who provided
the PASS-R Engineered Emulsion.
The City of Palm Desert has long
been a leader in the utilization of
environmentally friendly and cost
effective solutions and CCPR simply
represented another way they could
maximize taxpayer dollars while
continuing to protect their
infrastructure. James Emerson with
Pavement Recycling Systems
comments, “The City of Palm Desert
has utilized other rehabilitation
California Asphalt Magazine • 2012 Asphalt Rehabilitation Issue
methods in the past such as edge
grinding and overlaying with a 2”
Asphalt Rubber Hot Mix (ARHM) cap.
The City was looking for more
sustainable cost effective technologies
and the idea of recycling the City’s
existing asphalt assets made good
sense and provided an exceptional
value engineered alternative. The
environmental benefits of the process
also fit well with the City’s commitment
to reduce energy output. In addition
to the recycled pavement, the City
looked at utilizing a rubberized
asphalt hot mix or a warm mix asphalt
(WMA) for the wearing course. The
warm mix asphalt was selected
because of the significant cost
savings and it further benefited the
City by reducing emissions and the
amount of energy needed to produce
the product. Both the City of Palm
Desert and its local residents are very
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CAM Asphalt Rehab 2K12_CAM BOOK 2012 5/1/12 3:19 PM Page 18
Above: CCPR asphalt is readily compacted in compliance with the project specifications.
Inset: CCPR asphalt is easily installed with conventional paving equipment and allows for maximum production.
pleased with the results of the CCPR
method. The City has received several
comments concerning the speed in
which this process was facilitated and
the minimal impact it had on the
residents. Since the project was
completed, the City has finished
another CCPR project and is under
construction with its third CCPR
project. Additionally, the City has
used Cold In-place Recycling (CIR) on
two other arterial roadway projects.
The City will continue to look to use
these methods in the future.”
The overall project began in July of
2010 and was completed on time
and without change orders or time
extensions in August of 2010. The
pavement section encompassed
950,000 square feet, including
Panorama Drive, Abronia Trail, a
segment of Shadow Mountain Drive
and a number of smaller streets. As
part of the CCPR process, the existing
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asphalt pavement is removed in areas
from 2.5 inches to 4 inches. More
than 20,000 tons of existing asphalt
material was then taken to Pavement
Recycling Systems’ mobile plant,
located just a quarter-mile away, where
it was then crushed to 1” minus
gradation. Next, the crushed asphalt
was loaded into the self-contained
portable recycling unit, weighed and
sent through a dual-shaft pug mill,
where the engineered emulsion was
added at the prescribed design rate
per mix design. The material was then
loaded into trucks and taken out to
the paving operation where it was
loaded into Matich Corporation’s
paving hoppers. The newly revitalized
pavement was then spread at a
minimum rate of 4 inches loose in
order to achieve a compacted depth
of 3 inches. A double steel drum
vibratory roller and a 25-ton minimum
pneumatic roller were used to achieve
proper compaction. Quality control
testing assured maximum density
and maximum compaction. Upon
completion of the placement of the
recycled asphalt, a 1.25-inch warm
mix asphalt cap was installed.
The entire process was completed
on time, on budget and with only a
few minor issues. James Emerson of
Pavement Recycling Systems
explains, “The Cold Central Plant
Recycling method enabled the City of
Palm Desert to reconstruct the entire
asphalt section on Project # 752-10,
eliminating all cracks and restarting
the design life, all within their budget.
The challenges were minimal;
however working around the utilities
on this project was a slight issue, as
they were not double adjusted
(lowered prior to work, raised to finish
elevations after work). The City has
now gone to double adjusting of all of
their utilities, which will result in
California Asphalt Magazine • 2012 Asphalt Rehabilitation Issue
CAM Asphalt Rehab 2K12_CAM BOOK 2012 5/1/12 3:20 PM Page 19
Above: The CCPR asphalt reduced the
impact on the community and the
environment.
Far Left: Standard quality control
testing and inspection methods are
incorporated into the CCPR process.
improved future paving operations
and less impact on residents. We are
very proud to have worked with the
City of Palm Desert, Matich
Corporation and Western Emulsions
on this project and look forward to
more projects in the future. At
Pavement Recycling Systems, we
believe the CCPR method is much
more durable than a simple overlay,
with an estimated 20-year life span.
Since the existing asphalt pavement
is recycled, the costs, carbon emissions
and added traffic associated with
trucking material long distances is
eliminated.”
Utilization of the asphalt recycling
strategies allowed for rehabilitation of
the full scope of the design plan
within the City’s allocated budget.
Total construction costs, including
traffic control, dig-outs, striping and
loop detectors on this project came to
$1,990,803, with the recycled
asphalt saving the City of Palm Desert
an estimated $450,000. The CCPR
method eliminated approximately
2,600 truck trips that traditional
milling, removal and hauling would
have required and also kept the asphalt
material out of the landfill. In addition
to saving taxpayer dollars, the CCPR
process also provides significant
energy savings and a dramatic
reduction in the carbon footprint.
With national, state and local road
dollars being in short supply, it is easy
to see why Cold Central Plant Recycling
is being used increasingly more to
revitalize infrastructure. Maintaining
good quality roads is a top priority for
every agency across the United
California Asphalt Magazine • 2012 Asphalt Rehabilitation Issue
Left: The completed CCPR asphalt
section is turned over to traffic at the
end of the day.
States. The national transportation
research group, TRIP, estimates that
poor road condition is a factor in more
than 50% of all traffic fatalities. Safer,
more affordable and more
environmentally friendly roads just
make sense in today’s compromised
world. For more information on Cold
Central Plant Recycling, please call
Pavement Recycling Systems at
(951) 682-1091 or visit them online
at www.pavementrecycling.com. You
can also view a video of the City of
Palm Desert project at
http://www.youtube.com/watch?v=pN5J-xl6-s. CAM
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