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Volume 42, Number 5
August 9, 2006 |
What's
Next?
Looking at the Next 50 Years of the Interstate
The
U.S. Interstate highway system officially commemorated
its 50th anniversary on June 29, and although much attention
is focused on the first 50 years, many transportation
leaders are asking "what's ahead for the next 50 years?"
Norman Y. Mineta, former Secretary of the U.S. Department
of Transportation, in his farewell address, expressed
some concerns and some hopes that underscore the critical
needs of the system.
"Our transportation system today is at a critical juncture
that cries out for bipartisanship-or, more accurately-for
statesmanship."
"And, while we have laid important legislative and policy
foundations over the last five-and-a-half years, continued
progress requires facing some basic truths," Mineta said.
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These
truths, he said, include: the economic implications of
transportation, security, safety, and congestion, he said
in his farewell remarks.
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Facing
basic truths
... Mineta said basic truths are key to meeting future transportation
needs. |
Beyond
Highway Issues
As
we look ahead to the next 50 years, these and other topics
must be among the top focal points for all of us in the transportation
community, says Leif Wathne, P.E., the American Concrete Pavement
Association's Director of Highways.
Wathne said the challenges that lie ahead for the Interstate
transcend traditional highway issues. "Our charge as an industry
association," he said, "will be assisting our members and
our agency/owner customers to address some key issues, including:
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• Meeting Future
Capacity Requirements ... As the Secretary
said, "the modern economy-and by extension, our transportation
systems-are global in nature."
"The net effect," Wathne said, "is a sharp increase
in traffic and cargo moving across the Interstate
highway network. We must take a 'macro' view of the
nation's complete intermodal transportation system,
but we cannot lose sight of the importance of highways
in the equation.
"Eventually, we must expand the Interstate highway
network, as well as other highways and connectors,
to be able to assure connectivity among airfields,
ports, rail terminals, and other facilities.
• Providing Better Return on Investment
... Wathne also
said agency/owners-and indeed, legislators and taxpayers-must
be assured a better return on investment.
"We simply cannot keep increasing the investment in
the highways without showing tangible return on that
investment," he said, adding that the paving material
is a key factor.
"Concrete pavements have traditionally provided owners
with the best value, when compared on the basis of
life-cycle costs," he said, "but now, a growing number
of state and local agencies are seeing liquid asphalt
prices rise to such extremes that concrete is the
clear choice on initial investment, too."
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Making a Tangible Difference in Safety and Security...
"Road-users
should be enraged by the staggering statistic of more
than 43,000 highway fatalities," Wathne said, noting
that some 13,000 of those are believed to be attributable
to roadway conditions. "Road-users and agency-owners
deserve better," he said.
"Safety is a complex issue that requires actions on
a lot of different fronts, but the safety benefits
of concrete are well documented," he said.
For example, the light reflectance of concrete translates
to better nighttime visibility, and its dimensional
stability and wear resistance ensure that the as-designed
frictional and drainage characteristics remain intact
for the duration of the pavement's life.
Moreover, Wathne said, concrete pavements need very
little maintenance and require less frequent repair
and replacement than asphalt. As a result, there are
fewer work zones, which reduces the dangers to road
crews and motorists alike.
• Getting a Handle
on Sustainability ...
Sustainability
is coming, but unfortunately, the concept is not well
understood by all stakeholders.
Sustainability, in its simplest terms, is the way
the transportation community must both adopt and then
balance environmental stewardship, business requirements,
and the needs of society.
"A crucial element of sustainability is longevity,"
Wathne said. "Concrete pavement does not require rehabilitation
or reconstruction as often, and therefore consumes
fewer raw materials, and therefore is more compliant
with sustainable development goals.
Beyond that, Wathne, said, concrete offers some inherent
environmental and societal benefits, including:
++++++ ° Light reflectance
... because of its lighter color, concrete requires
fewer light fixtures and less energy to illuminate
than asphalt pavements. Pedestrian and motorist safety
are also improved as well, due to improved nighttime
visibility.
++++++ ° Recyclability
and co-generated materials… Concrete pavements
are a 100% recyclable material. In addition, significant
amounts of industrial co-generated materials (e.g.,
fly-ash, blast furnace slag, silica fume, etc.) are
used in concrete pavements, thereby minimizing the
load on our landfills, while enhancing pavement performance.
Also, an abundant supply of limestone, rock, and water
are the common ingredients of concrete pavements.
++++++ ° Helping urban
areas stay cooler ... Widely reported studies
show that light-colored, reflective building surfaces
such as concrete help reduce urban temperatures. Recent
thermographic images taken in Phoenix showed the ambient
temperatures to be an average of 15°F lower on concrete
surfaces than asphalt pavements. (See "Dramatic
Difference" graphic below.)
"Ultimately, all these environmental and societal
benefits add up to great long-term economic benefits
to the public," Wathne said.
For more information abut ACPA's solutions to meet
the challenges of the Interstate highway network,
contact Leif
Wathne at 202-638-2272...
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Thermographic images of asphalt (left) and concrete pavements (right)
indicate an approximate 15% differential in pavement surface temperatures.
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Pavement
Research Group Releases
New Version of Mechanistic Design Guide
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The
National Cooperative Highway Research Program (NCHRP) recently released
the latest version of the Mechanist-Empirical Pavement Design Guide
(M-E PDG).
"Version 0.9 of the guide will let users better predict pavement
performance as a function of time," said Mike Ayers, PhD, ACPA's
Director of Pavement Technology.
"The guide will be an important tool in optimizing pavement features
for long-life and in conducting life-cycle cost analysis," he
said. |
"There is ample room for local/regional calibration to better
fit specific conditions and performance history," he added. |
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The new version of the Guide will be balloted by the American Association
of State Highway and Transportation Officials' Subcommittees on
Design and Materials in the spring of 2007. It is likely that the
Guide will be released as an interim guide at that point.
ACPA will produce a series of R&T Updates based on the new M-E
PDG and optimizing pavements. They will be released in fall 2006
and early 2007.
For more information, contact Mike
Ayers at 217-621-3438.
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ACPA
Sponsors Nationwide
Contest to Celebrate Vacation Travel |
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ACPA is sponsoring the "Great American Family Road Trip"
essay contest.
The contest is aimed at how the Interstate highway enables families
to vacation together.
The essay contest encourages travelers to recall favorite driving
experiences —including how concrete pavements factored into
those experiences—on the way to or from a vacation destination.
Until September 4, contestants have the opportunity to enter the
contest by submitting a 500-word essay about a family road trip. |
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Winners
will be awarded one of several prizes: a $500 gas gift card; a
$250 gas gift card; a $100 gas gift card; and two $50 gas gift
cards. Ten entrants also will be awarded road atlases.
Click here
to read the official contest rules, and then click here
to download an entry form.
For more information, please contact Bill
Davenport at 847-966-2272. |
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Concrete Pavement Offers
Safety, Smooth Ride to Seattle Motorists
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| ...Copyright 2006,
American Concrete Pavement Association |
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When
the Washington State DOT needed to rehabilitate a section of Interstate
5, one of Seattle's most heavily traveled highways, they specified
concrete pavement.
The highway had become a "patchwork of asphalt and concrete,
because we previously created new lanes by paving shoulders with
asphalt and then re-striping the roadway," according to the
Washington State DOT. The original concrete, placed in the mid-1960s,
held up well under 40 years of traffic, estimated at 122,000
vehicles
per day.
After
years of "cracks, potholes, and costly and disruptive temporary
repairs," the DOT decided it was time for a more lasting
solution. The rehabilitation project included two outside lanes
of Interstate 5 (between James Street and Olive Way), an exit
under the Convention Center, and bridge repairs.
Officials
knew the reconstruction would be challenging for several reasons,
including the requirement to construct under traffic, as well
as some tight working spaces within the construction zone. Also,
Seattle's wet-weather conditions postponed construction on five
weekends. Officials also knew reconstruction of the well-traveled
section would attract considerable attention.
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The
reconstruction was considered a major pilot project for almost
40 lane-miles slated for replacement by the Washington State DOT.
The contract, in addition to establishing best methods for paving
under heavy traffic, would be instrumental in determining if concrete
will be used in future projects, according to a fact sheet by
Gary Merlino Construction Co., Inc., Seattle.
Setting the Stage
"After
monumental efforts, years of public education and public relations
work,
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additional gas
taxes
were
passed
by
razor-thin
margins
to fund roadway improvements," according to Merlino.
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On
the move ... Photo illustrates traffic conditions and tight
working conditions of the project. (Photo
courtesy of the Washington State DOT)
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Click here to see other project highlights.
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The contract involved removing existing shoulders, right travel
lanes, and off-ramps, and then replacing the pavement with 13
in. of concrete.
Other challenges included staging, said
Bob Pipinich, Project Manager for Merlino
Construction, an ACPA member, which served as general contractor.
Pipinich noted the project was completed in four phases. Each
stage had to be completed in its entirety in one 55-hour weekend.
ACPA member, the Salinas Construction Co., Everett, Wash., was
one of the subcontractors that helped complete the project on
time.
"We had to route access routes right through the middle of the
city in conjunction with a tight timeframe of between 10 p.m.
Friday through 5 a.m. Monday," Pipinich said, adding, "We staged
operations by the half-hour."
"Everything—the materials and the equipment—had
to be pre-staged and ready to go as soon as 10 o'clock hit,"
Pipinich said. "All of the pavement had to be cured and joints
sealed prior to reopening to traffic on Monday mornings."
To facilitate the process, Merlino used used maturity meters to
determine strength for reopening to traffic, Pipinich said, noting
that the meters provided accurate readings immediately.
Smooth and On-Time
In addition to meeting the smoothness requirements (7 in./mi.),
Pipinich also said the project involved some stringent requirements
for on-time completion.
"Since the work controlled most all of the southbound exits
into downtown Seattle, as well as the southbound access to Interstate
90, the contract penalties were very substantial," he said.
"A delay in opening the freeway on time carried a liquidated
damage of up to $10,000 for each 15-minute delay. If we had to
add an additional weekend, it would have carried a penalty of
$100,000.
"No penalties were incurred," he said.
In spite of wet weather, the requirement to pave under traffic,
and other challenges, the project was completed on time. Equally
important, motorists traveling through downtown Seattle now have
a durable and smooth pavement that the DOT says, "improves
safety because vehicles no longer have to weave around cracks
or potholes."
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Project Highlights
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Durability
of the original concrete pavement: 40 years.
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Vehicles
per day traveling southbound: 122,000.
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Amount
of old asphalt pavement removed:
6,300 cubic yards or 350 truckloads.
» Amount
of new concrete placed: 700 truckloads, or 5,100 cu.
yds.
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Construction information
fliers delivered to nearby residences and business: 36,000+
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Getting
it done ...
In tight quarters, paving was done by hand. (Photo
courtesy of the Washington State DOT.)
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Fliers delivered to residences and businesses (within
500 ft. of the project): 750
(Source: Washington State DOT)
Return
to mainstory
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| Match
...
Matching the new slab to the old was another aspect of the
project performed by hand. (Photo courtesy
of the Washington State DOT.) |
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Pavement
Preservation Techniques Keep Roadways in Service
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Pavement
preservation refers to all the actions taken to provide and maintain
serviceable roadways, including corrective and preventive maintenance,
as well as minor rehabilitation projects, according to the Foundation
for Pavement Preservation.
The concrete pavement industry has developed a strategy for assessing
pavement conditions and applying the best preservation technique(s)
to return a concrete pavement to like-new condition.
A subset of these pavement preservation techniques is known as concrete
pavement restoration (CPR), which is used to restore a moderately
distressed concrete pavement to like-new condition.
CPR
techniques include diamond grinding, full-depth repair, partial-depth
repair, slab stabilization, load-transfer, and joint resealing,
among others.
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Among the first considerations should be the type(s) of preservation
technique(s) to apply, based on the type and amount of deterioration
present in the candidate pavement. |
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Diamond
grinding is used to restore concrete pavements. |
The basic process involves assessment to determine whether the distress
is structural (which affect the pavement's ability to carry traffic)
or functional (which may affect ride quality and safety, but do not
impact the pavement's load-carrying capability).
Preventive CPR techniques include:
• Joint and crack resealing to minimize the infiltration of surface
water and incompressible materials into the joint system;
• Retrofitting concrete shoulders to decrease edge stresses and corner
deflections, as well as to reduce the potential for transverse cracking,
pumping, and faulting;
• Retrofitting edge drains by adding a longitudinal drainage system
to assist in the removal of water that may cause pumping, faulting
and durability distress.
Corrective and preventive CPR techniques include:
• Dowel bar retrofit to increase the load transfer efficiency at transverse
cracks and joints;
• Slab stabilization to restore the support to concrete slabs by filling
small voids that develop under the concrete slab at joints, cracks,
or the pavement edge.
• Full-depth patching, i.e., removing and replacing at least a portion
of a slab to the bottom of the concrete, to restore areas of deterioration.
Full-depth patches improve pavement rideability and structural integrity
and extend pavement service life.
• Partial depth patching to restore localized areas of deterioration
that do not extend through the slab.
• Diamond grinding to remove bumps and re-profile the surface of concrete
pavements. This improves the riding comfort to motorists and decreases
the severity of dynamic or impact loads from heavier vehicles.
ACPA has a range of technical resources that address pavement preservation
and CPR techniques. These include "Concrete Pavement Repair Manual
" (JP002); Pavement Rehabilitation Strategy Selection (TB015P); and
"CPR for City Streets" (CD023P).
To order ACPA publications, go to the ACPA website, www.pavement.com;
call toll-free 1- 800-868-6733; or fax requests to 847-966-9666.
Contact Mike
Ayers at 217-621-3438 for more information or if you have any
questions about this article. Would you like to submit a technical
question? Send an email to ACPA or call Bill
Davenport or Erin McKnight
at 847-966-2272. |
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Study
Projects Increase in Long-Term Cement Consumption ... The United
States' annual cement consumption is expected to grow to nearly
195 million metric tons by 2030, according to a Long-Term Cement
Consumption Outlook released by the Portland Cement Association.
This reflects a 1.7% compound annual growth rate. Increased U.S.
population and the expected demand for housing, commercial buildings,
public buildings, and infrastructure will fuel this increase as
will an expected 25% increase cement consumption per capita.
The cement industry is currently engaged in an aggressive $3.9 billion
capacity expansion. Market growth coupled with decreased foreign
reliance on cement import should result in complete absorption of
the expected new capacity. Click here
for more information, or to order the publication.
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ACPA Concrete
Pavement Progress is published 12 times per year and covers
current practices and case histories in the concrete pavement industry.
ACPA Concrete Pavement Progress is distributed free
of charge to public officials, ACPA members, executive committee,
board of directors, and affiliated chapter/state paving associations.
All rights reserved. Copyright
2006 by the American Concrete Pavement Association. No portion of
this publication may be reproduced mechanically or electronically
without the expressed written permission of the American Concrete
Pavement Association.
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American Concrete Pavement Association
5420 Old Orchard Road, Suite A100
Skokie, IL 60077
Phone: 847-966-2272. Fax: 847-966-9970
(Washington) 1130 Connecticut
Ave., N.W.
Suite 1250
Washington, DC 20036
Phone: 202-887-8290. Fax: 202-887-8298
(Mesa, AZ) 807 W. Keating Ave.
Mesa, AZ 85210
Phone: 480-775-0908
Visit our website at http://www.pavement.com/ |
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2006 Chairman,
ACPA Board of Directors
Peter Deem, Holcim (US) Inc.
2005 Vice-Chairman, ACPA Board of Directors
Pat Nolan, Interstate Highway Const.,
Inc. (IHC)
2006 Communications Committee Chairman
Mike Roth, Lehigh Southwest Cement Co.
ACPA President/CEO - Gerald F. Voigt, P.E.
Editor - Bill Davenport
Managing Editor - Erin McKnight
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