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Asphalt Pavement Recycling
Benefits of Asphalt Pavement Recycling:
• Cost Savings
• Conservation of Aggregate and Asphalt
• Preservation of Existing Pavement Geometrics
• Preservation of Environment
• Conservation of Energy
• Elimination of Reflective Cracking due to Overlay
POTENTIAL COST SAVINGS
DATA: (1990 prices) (2006 prices)
Asphalt Cement - U.S.$120.0/Ton $400/T
Aggregate (1) $7.0/Ton $20/T
(2) $12.0/Ton
VIRGIN MIX (1) (2)__
* Asphalt (6%) $ 7.20/T $ 7.20/T $24.0
* Aggregate $ 6.58 $11.28 $18.4
Material Cost $13.78 $18.48 $40.4
Processing Cost $ 5.00 $ 5.00__
Plant Cost $18.78/T $23.48/T
RECYCLED MIX USING 30% RAP
Material Saving -$ 4.13 -$ 5.54 -$12.1
Total Cost $14.65/T $17.94/T
Saving 22.0% 23.6%
Basic Mechanism in Asphalt
Pavement Recycling
Reclaimed Asphalt Pavement (RAP) contains:
(1) Hard asphalt binder
(2) Degraded aggregate
Recycling of RAP involves:
(1) Adding appropriate type and amount of recycling agent
(or soft asphalt) to soften the binder.
(2) Adding appropriate type and amount of virgin coarse
aggregate to correct the gradation of the degraded
aggregate.
Categories of Asphalt Pavement
Recycling
• Hot Mix (Central Plant) Recycling
• Cold Mix (Central Plant) Recycling
• Hot In-Place (Surface) Recycling
• Cold In-Place (Surface)Recycling
• Full Depth Reclamation (or Cold In-Place
Surface and Base Recycling)
Hot Mix Recycling:
RAP (Reclaimed Asphalt Pavement) is combined with new
aggregate and asphalt binder or recycling agent in a hot
mix plant. Mix is transported to paving site, placed, and
compacted.
Cold Mix (Central Plant) Recycling:
RAP is combined with new aggregate and asphalt binder or
recycling agent in a central plant without application of
heat. Mix is transported to paving site, placed, and
compacted. A wearing course is usually placed over the
cold recycled mixture.
Hot In-Place (Surface) Recycling:
Existing asphalt surface is heated, scarified to a
depth from ¾ to 2 inches (20 to 50 mm). Scarified
material is combined with aggregate and/or
asphalt binder and/or recycling agent and
compacted. New overlay may or may not be
provided.
Cold In-Place (Surface) Recycling:
Existing asphalt surface is milled. RAP is reduced if
needed, mixed with recycling agent in-place,
placed, and compacted.
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