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1 HIGH RAP % IN HMA CALAPA TECH MEETING SAN DIEGO July 18, 2012
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HIGH RAP % IN HMA CALAPA TECH MEETING
SAN DIEGO
July 18, 2012
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CITY OF LOS ANGELES
6500 Miles of improved roads 5800 Miles – Asphalt Concrete Annual Resurfacing budget of $45
million.
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CURRENT % RAP ALLOWED
Caltrans – HMA – up to 15% – Superpave – 25% +/-1
Green Book – Section 203-6 – up to 15% Section 203-7 – >15%
City of LA Contract – 50% RAP
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WHY RECYCLE?
– Landfill shortage. August 11,1987 City order prohibiting
the landfilling of road materials. Beneficial Use Excellent performance
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CYCLEAN
The process used microwave technology to produce HMA at up to 135 tons/Hr
Plant would consume over 200,000 tons of City RAP in 1992 saving the city $1.5 M in raw material and disposal cost.
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CITY OF LOS ANGELES
Uses own equipment and personnel to mill pavements for profiling and grind-out procedures
Millings transported to two locations for stockpiling
Contract requires the use of COLA millings.
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MIX DESIGN PROCESS
Extensive profiling of RAP. Several samples have to be tested. Extraction and recovery of individual
samples. PG grading of RAP - +PG 82 Blend to PG 64 -10
Recycling Agents (ASTM D4552)
RA1 RA5 RA25 RA75 RA250 RA500 Viscosity @
60C (cSt) 50-175 176-900 901- 4500
4501- 12500
12501- 37500
37501- 60,000
Flash Point, C, Minimum
218 218 218 218 218 218
Saturates, %, Minimum
30 30 30 30 30 30
Viscosity Ratio (RTFO or TFO)
3 3 3 3 3 3
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Mix Design Procedures
Asphalt Content, Aggregate Gradation and PG or RAP
Gradation of New Aggregate Combined Gradation of Recycled Mix 75 Blow Marshall Mix Design per COLA
Brown Book
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Testing
Extensive QC Testing – Gradation and AC% on RAP – Gradation on aggregates – PG 64 -10 and Recycling Agent – 75 Blow Marshalls
Extensive QA testing – 4 to 8 samples – 75 Blow Marshalls – Superpave for ARRA jobs
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RAP Processing
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Stockpiling
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Finished Product
½” minus RAP
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Los Angeles Regional Lab
Viscosity Testing
Extraction/Recovery
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Questions Pascal Mascarenhas
Vulcan Materials [email protected]
626-856-6190 Phone 626-969-2918 Fax 626-705-6606 Cell
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THANK YOU
