Evaluating the Effect of Coarse Rubber Particles on Asphalt Concrete Mixtures

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Evaluating the Effect of Coarse Rubber Particles
on Asphalt Concrete Mixtures

• James K. Laicovsky
• Laura C. Miller
• Amanda R. Zimmerman

The 18th International Conference on Solid Waste
Technology and Management Philadelphia, PA
March 25, 2003
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Outline of Presentation

• The Tire Problem
• Superpave
• Project Scope
• Results

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Waste Tires
Total 300 Million Tires 2.5 Million Tons
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Solid Waste in the U.S.
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(No Transcript)
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Solution
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Recent Projects
Northeast
Washington
85 of scrap tires are located in -- Connecticut,
New York, Pennsylvania , Ohio, Michigan,
Colorado, Virginia, Texas, and Alabama.
Tennessee
Arizona
Texas
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Superpave

• SUperior PERforming Asphalt PAVEments
• Strategic Highway Research Program
• New techniques to specify, test, and design

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Project Scope

• Rubber Analysis
• Gradation Manipulation
• Rubber Substitution
• Specimen Fabrication
• Specimen Testing
• Fine-Tune Rubber Substitution

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Gradation Manipulation
Desired Superpave Gradation Curve
Percent Passing
Sieve Size.45
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Rubber Analysis
¾ Rubber Particles
4 Rubber Particles
12 Rubber Particles
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Rubber Substitution

• Substituted Rubber into Original Superpave
  Gradation
• 0.5 - 5.0

Rubber Particles
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Specimen Fabrication

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Specimen Fabrication
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GC Data
Compaction Height, cm
Gyration, N
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GC Data Analysis
Area ½(H1-H2)(log100-log1)
H1
Slope k
k
Air voids at 100 gyrations Lower the number,
softer mix
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H2
0
100
Log (Number of Gyrations)
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GC Data Plot
Compaction Height, cm
Log (Number of gyrations), N
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Results
Area Under k Curve vs. Rubber Substitution
Area Under k Curve
Rubber Substitution,
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Analysis

• 4 rubber substitution uses
• 60 tons of GTR 7,600 tires/lane mile
• Rubber cost 10,000/lane mile

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Analysis

• 4 rubber substitution reduces
• 780 tons of aggregates
• 156,000 savings/lane mile

Savings of 146,000/lane mile
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Conclusions

• Improved rutting performance.
• Potentially useful with NJ aggregates.
• Continued investigation to determine optimal
  substitution percentage.

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Web Site
http//engineering.rowan.edu/mill2633/rowan_rubbe
r.htm
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QUESTIONS?