What is Hot-Mix Asphalt?
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Hot
Mix Asphalt (HMA)
is the material of choice for a variety of projects that improve our
daily lives and our environment. A few of the many benefits it can
provide are: |
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Reduced
traffic noise |
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Increased
wet-pavement friction for improved safety |
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And it’s
100% recyclable, which saves our natural resources. |
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The
versatility of HMA goes far beyond pavements, driveways and parking
lots. It is also being used for liners of fish rearing ponds and
domestic water reservoirs, for recreational paths and for industrial
sites. It is the pavement of choice for an increasing variety of
recreational and environmental purposes such as golf cart paths,
sludge-drying beds, silage pits, work platforms at agricultural sites,
and as revetments protecting roadway slopes and populated areas against
flood damage.
. . . HMA
has proved to be a versatile, environmentally friendly construction
material. For additional information regarding the environmental
benefits of HMA, visit the web site of the Asphalt Institute at
http://www.asphaltinstitute.org/. |
What
is SuperPave?
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From
October 1987 through March 1993, the Strategic Highway Research Program
(SHRP) conducted a $50 million research effort to develop new ways to
specify, test, and design asphalt materials. The final product of the
SHRP asphalt research program is a new system referred to as
SuperpaveTM, which stands for Superior Performing Asphalt Pavements. It
represents an improved system for specifying the components of asphalt
concrete, asphalt mixture design and analysis, and asphalt pavement
performance prediction.
. . . Superpave is a comprehensive system
for the design of paving mixes that are tailored to the unique
performance requirements dictated by the traffic, environment
(climate), and structural section at a pavement site. It enhances
pavement performance through the selection and combination of the most
suitable asphalt binder and aggregate. (More
Information) |
What is SMA?
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SMA
(Stone
Matrix Asphalt) is
a tough, stable, rut-resistant mixture that relies on stone-to-stone
contact to provide strength and a rich mortar binder to provide
durability. Its use in the United States began in 1991 and is
increasing rapidly. The estimated 20-25% increase in cost is more than
offset by the increase in life expectancy of the mix, primarily through
decreased permanent deformation and increased durability. SMA is
considered to be a premium mix by several state Departments of
Transportation for use in areas where high-volume traffic conditions
exist and frequent maintenance is costly. The Illinois Department of
Transportation has included the use of SMA, as the primary surface
course required for Extended Life HMA pavement projects. |
What is Perpetual Pavement?
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Perpetual
Pavements
made of asphalt represent a new approach to road building that could
extend the design life of an asphalt pavement to 50 years or even more,
while improving safety and cutting both the time and cost of
construction and maintenance. |
What is Full-Depth Asphalt?
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Full-Depth
Asphalt Pavement: Pavement in which asphalt mixtures are used for
all courses above the subgrade or improved subgrade. |
Why Asphalt?
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Of the
dozens upon
dozens of reasons why asphalt is your best choice, here are just a few
of the leading reasons: |
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Asphalt
is
America's Most Recycled Product -- Asphalt's recyclability
offers unsurpassed reductions in cost and waste. |
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It’s
“The
Smooth, Quiet Pavement” -- Asphalt's quiet ride is an
environmental benefit appreciated by homeowners and motorists alike. |
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It’s
Also
Extraordinarily Versatile
-- There’s a Hot Mix Asphalt pavement design and material selection
that is right for just about every situation, from heavily traveled
urban interstates to bike paths to reservoirs. |
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For
Speed of
Construction, Asphalt is Unsurpassed
-- Asphalt can be placed faster than other paving materials; nearly 10
times as much road was paved with asphalt that concrete, in less time.
It also minimizes impacts on neighborhoods and businesses due to road
closures |
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For both
the short
term and the long haul, Asphalt Pavement Saves Money on
Construction and Maintenance. It’s what engineers call the life-cycle
cost of a road, which includes the money spent both on initial
construction of a road and
maintenance over its lifetime. Life-cycle costs of Hot Mix Asphalt
pavements are significantly lower than those of Portland cement
concrete pavements. |
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What is in Asphalt?
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What
most people mean when they say “asphalt” – also known as blacktop,
macadam, or tarmac – is actually a particular product, known in our
industry as asphalt pavement, or sometimes, Hot Mix Asphalt (HMA)
pavement.
. . . There
are two basic ingredients in Hot Mix Asphalt. The first is aggregates
(crushed stone, gravel, and sand).
The aggregates used are almost always locally available stone. About 95
percent of the total weight of an asphalt pavement consists of
aggregates.
. . . The
remaining five percent is Asphalt Cement, the black liquid
that acts as the glue to hold the pavement together.
Asphalt Cement (AC) is a petroleum product generally obtained from the
same refineries that produce gasoline for your car and heating oil for
your house. Asphalt Cement is one of the heaviest, most viscous parts
of petroleum.
. . . Mix the
two ingredients together, and you get Hot Mix Asphalt. |
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SOURCE -
NAPA |
Is all Asphalt the Same?
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UNDER
DEVELOPMENT |
Is Asphalt Environment-Friendly?
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The
Asphalt Institute web site has an extensive array of environmental
information for the user. The summary below is from their web site,
under “Environmental Information.” |
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http://www.asphaltinstitute.org/environ/envirobrief.htm#Summary |
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"Hot
mix asphalt is the material of choice for a variety of projects that
improve our daily lives and our environment. From liners for fish
rearing ponds and domestic water reservoirs, to recreational paths and
industrial sites, HMA has proved to be a versatile, environmentally
friendly construction material.
. . . “In
addition to the uses described earlier, hot mix asphalt is the pavement
of choice for an increasing variety of recreational and environmental
purposes such as golf cart paths, sludge-drying beds, silage pits, work
platforms at agricultural sites, and as revetments protecting roadway
slopes and populated areas against flood damage." |
How should I do my Driveway?
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Hot
Mix Asphalt is the most cost-effective option you can choose. Just as
it has for millions of homeowners the world over, Hot Mix Asphalt can
last many years for you — with only minimal maintenance. (More
Information) |
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