This document discusses the use of recycled asphalt pavement (RAP) in road construction. It notes that RAP meets the three main requirements of a pavement: being cost effective, environmentally responsible, and able to perform well. While RAP makes up a small percentage by weight of asphalt, it represents a large percentage of the material's value. The document also summarizes a study finding that RAP pavements can perform equally or better than virgin pavements, though specification limitations and lack of processing and availability have held back more widespread use of RAP.

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Carl Christian Thodesen
Recycling
of
Asphalt Pavements

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PEOPLE
PROFIT
PLANET

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1. Warm mix
2. Doubling reclaimed materials use
3. Increased use of porous
pavements
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6. Technology for a better society
1. Warm mix
2. Doubling reclaimed materials use
3. Increased use of porous
pavements
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What are the three most
important requirements of
a pavement with RAP?

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1. Cost effective
2. Environmentally responsible
3. Perform well
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1. Cost effective
2. Environmentally responsible
3. Perform well
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binder
4%
aggregate
96%
1 ton asphalt: by weight

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binder
62%
aggregate
38%
1 ton asphalt: by value

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RAP is a valuable resource

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1. Cost effective
2. Environmentally responsible
3. Perform well
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Santero, N., E. Masanet, and A. Horvath. 2011. “Life-Cycle Assessment of Pavements Part I: Critical Review.” Resources, Conservation, and
Recycling. 55(9–10):801–809.

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Rolling Resistance: Roughness
Rolling Resistance: Structure
Albedo: Radiative Forcing
Albedo: Urban Heat Island
Roadway Lighting
Carbonation
Traffic Delay
Onsite Equipment
Transportation
Materials
Global Warming Potential
(Mg CO2e/lane-km)
100 101 102 104
103 105
Santero, N., E. Masanet, and A. Horvath. 2011. “Life-Cycle Assessment of Pavements Part I: Critical Review.” Resources, Conservation, and
Recycling. 55(9–10):801–809.

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RAP is environmentally
friendly

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1. Cost effective
2. Environmentally responsible
3. Perform well
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• Statistical Comparison of pavements
• 35% RAP pavements vs. virgin pavements
• Data from 5 test sections
• Pavement sections from 6 -17 years old
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Hong, F., et al. (2010). “Long-Term Performance Evaluation of Recycled Asphalt
Pavement Results from Texas: Pavement Studies Category 5 Sections from the
Long-Term Pavement Performance Program,” Transportation Research Record
2180, Transportation Research Board, Washington, DC.

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• IRI
• Rutting
• Fatigue cracking
• Longitudinal cracking
• Transverse cracking
• Block cracking
• Raveling
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Virgin performed
significantly
better than RAP
42%
RAP performed
significantly
better than
virgin
39%
Insignificant
difference
between RAP
and virgin
19%
IRI

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0
25
50
75
100
%RAPpavementsperformingequalor
betterthanoriginal

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RAP pavements can
perform

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What is holding us back?

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• Specification limitations
• Lack of processing
• Lack of RAP availability
• Past experiences
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Summary

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• RAP is a valuable resource
• RAP is environmentally friendly
• RAP pavements can perform
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Technology for a better society
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