ASPHALT RUBBER 2000 Summary of the Conference

1
ASPHALT RUBBER 2000Summary of the Conference

• About 220 Registrations
• About 185 Attendees
• 33 Countries
• 40 Papers
• Site Visit to Crumb Rubber Factory and
  Construction Site

2
Dispel the Myths about Asphalt Rubber (with 20
crumb rubber - wet method)

• Field Performance
• Way, Shatnawi, Potgieter, Van Heystraeten,
  Watkins
• Cost Effectiveness
• Watkins, Way, Hicks
• Environmental Effects and Benefits
• Turner, Carlson

3
Other Areas Covered

• Laboratory Comparisons of Performance
• Different Materials Presented
• Binder and Mix Testing
• Different Materials Presented
• Accelerated Pavement Testing
• Different Materials Presented
• (Most of the times laboratory results were in
  line with field observations however
  occasionally laboratory results and conclusions
  did not correlate with field observations)

More Research!
4
Functional Properties

• Skid Resistance
• Noise Reduction
• Texture

5
Asphalt Rubber?

• Wet Method (with 18-22)
• Wet Method (15)
• Wet Method (10) - Terminal Blend
• Wet Method (5 SBS) - Terminal Blend
• Wet Method (3.5) - Terminal Blend
• Dry Method - 1, 2, 3 of aggregate mass - Short
  and Long Reaction times
• Proprietary Methods (no technical info!)

6
No evidence presented that ADOT or CALTRANS
method (wet method with 18 - 22 crumb rubber)
cannot be implemented and used in most parts of
the world(on the contrary!)
7
Gap-graded?

• The Americans have started misusing this term to
  describe a grading similar to an SMA or
  open-grading. Be alert to this fact when reading
  US literature.