evaluating the effect of coarse rubber particles on asphalt concrete mixtures james k. laicovsky...
TRANSCRIPT
Evaluating the Effect of Coarse Rubber Particles on Asphalt Concrete Mixtures
James K. LaicovskyLaura C. Miller
Amanda R. Zimmerman
The 18The 18thth International Conference on Solid Waste International Conference on Solid Waste Technology and Management Technology and Management
Philadelphia, PA Philadelphia, PA March 25, 2003 March 25, 2003
Outline of Presentation
The Tire Problem
Superpave
Project Scope
Results
Waste Tires
Total ~ 300 Million Tires
~2.5 Million Tons
Solid Waste in the U.S.
Scrap Tires = 1.5%
Commercial
&
IndustrialResidential
Solution
Recent Projects
85% of scrap tires are located in --
Connecticut, New York, Pennsylvania ,
Ohio, Michigan, Colorado, Virginia,
Texas, and Alabama.
Superpave
•SUperior PERforming Asphalt PAVEments
•Strategic Highway Research Program
•New techniques to specify, test, and design
Project Scope
Rubber AnalysisGradation ManipulationRubber SubstitutionSpecimen FabricationSpecimen TestingFine-Tune Rubber Substitution
Gradation Manipulation
Desired Superpave Gradation Curve
Sieve Size.45
Perc
en
t Pass
ing
Bad Mix
Good Mix
Good Mix Bad Mix
Rubber Analysis
¾” Rubber Particles
#4 Rubber Particles
#12 Rubber Particles
Rubber Substitution
Substituted Rubber into Original Superpave Gradation
0.5% - 5.0%
Rubber Particles
Specimen Fabrication
Specimen Fabrication Gyratory Compactor
1.25°
GC Data
112
117
122
127
132
137
142
0 10 20 30 40 50 60 70 80 90 100 110
0%
0.50%
1.00%
1.50%
2.00%
5.00%
Com
pacti
on
Heig
ht,
cm
Gyration, N
GC Data Analysis
Log (Number of Gyrations)
0 100
H1
H2
Area = ½(H1-H2)(log100-log1)
k
1
Slope = k
Air voids at 100 gyrationsLower the number, softer mix
GC Data Plot
110
115
120
125
130
135
140
145
0 0.5 1 1.5 2 2.5
Linear (0%)
Linear (0.50%)
Linear (1.00%)
Linear (1.50%)
Linear (2.00%)
Linear (5.00%)
Log (Number of gyrations), N
Com
pacti
on
Heig
ht,
cm
Results
245
250
255
260
265
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5
Area Under “k” Curve vs. Rubber Substitution
Are
a U
nd
er
“k” C
urv
e
Rubber Substitution, %
Analysis
4% rubber substitution uses:
60 tons of GTR ~ 7,600 tires/lane mile
Rubber cost ~ $10,000/lane mile
Analysis
4% rubber substitution reduces:
780 tons of aggregates
~ $156,000 savings/lane mile
Savings of $146,000/lane mile
Conclusions
Improved rutting performance.
Potentially useful with NJ aggregates.
Continued investigation to determine optimal substitution percentage.
Web Site
http://engineering.rowan.edu/~mill2633/http://engineering.rowan.edu/~mill2633/rowan_rubber.htmrowan_rubber.htm
QUESTIONS?