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- [Narrator] Making roadways
last longer is the goal

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of all pavement engineers.

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One of the keys to longer
life rests in the binders

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which are added to pavement mixtures.

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Researchers with the Center
for Transportation Research

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at the University of Texas
are developing new test

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methods that can help
them predict which binders

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will resist pavement distress,

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specifically rutting, fatigue cracking,

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and thermal cracking.

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- When you drive on asphalt
roads, asphalt binder is quite

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literally the glue that's
holding these roads together.

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It is also the most expensive material

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or component material that goes

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into production of asphalt mixtures

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and therefore the asphalt pavement.

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That inherent ability of the binder

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to resist cracking is what
dictates the serviceable

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life of an asphalt pavement.

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- There has always been a
need for tests or testing

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that can accurately detect
ability of an asphalt binder to

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resist cracking in the field.

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This is even more important
now as the binder industry

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or the binder manufacturers
are developing new types

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of modifiers and chemicals to
improve conditions of asphalt.

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- In the original research project

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we developed the poker chip test method

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and it showed some promise
that it was able to detect

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whether or not an asphalt
binder is susceptible

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to premature cracking or not.

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In the implementation
study, we did two things.

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One was, we made the test
very practical and easy to use

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by any technician in
any asphalt laboratory.

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And the second thing we did
was, we benchmarked the results

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from these tests, with the ground truth.

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We actually went down to
22 different sections all

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across the state,
different climatic regions,

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traffic volumes, mixture
types, pavement types,

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and benchmarked the parameters

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from this test with the ground truth.

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That is, if the test was
telling that this pavement

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is likely to crack prematurely,

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whether or not it was cracking or not.

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And we established that connection

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between ground reality and
what the test was telling us.

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- The main use for asphalt is hot mix.

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Asphalt mixture and asphalt binder

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is the most expensive part.

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We use about half a million
ton of asphalt binder annually.

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We're really looking at any improvement.

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Quality of that material will
have a really huge impact

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on the state in terms of
savings, as well as in terms

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of having, you know,
longer life pavements,

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getting more recycled material, as well

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as improving the quality
of what's practically

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the driving cost of our hot mix.

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- [Narrator] For more information,

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and to find the publications
for this project,

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please visit the Tex DOT research library

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at the link shown below.