New HMA & WMA Technologies
HMA & WMA Technologies Kent R. Hansen, P.E. Director of Engineering National Asphalt Pavement Association
www.store.asphaltpavement.org Pavement evaluation and project selection Materials and Mix Design Construction & Quality Control Performance
FG
4. D 75 FG D 9.5 FG 12 D .5 FG SM 19 A SM 9.5 A 1 SM 2.5 A O 19. 0 G FC O 9. G FC 5 12 . D CG 5 9. D CG 5 D 12. CG 5 19 .O
D
Min Lift Thick Range, mm
Recommended Mix Types Surface Courses Low Traffic Medium Traffic High Traffic
80 70 60 50 40 30 20 10 0
Mix Type
States increasing RAP use
States that have experimented with or routinely use high RAP mixtures
High RAP Performance The performance and life of pavement containing up to 30 percent RAP is similar to virgin pavements with no RAP. A survey of LTPP sections containing at least 30 percent RAP showed similar performance to virgin sections.
The Value of Milling
• Removes cracked and aged pavement surface • Improves pavement smoothness • Maintains curb height, drainage inlets, and bridge clearances • Improves bond with overlay Ref: Randy West, NCAT 3/30/2010
11
Using RAP to Maximize Your Pavement Dollar Kent Hansen, P.E.
RAS Why use asphalt shingles in asphalt pavement?
All materials commonly used in asphalt pavements
Sources Manufactures’ waste – Limited ~1 MT annual – Not in every state
Tear-offs – ~10 MT annual – Everywhere? State regulations Processors
08/26/2009
Recycling Asphalt Shingles into Asphalt Pavements Kent R. Hansen, P.E.
14
States Allowing RAS in Asphalt Mixes
08/26/2009
15
Pooled Fund Study TPF-5(213) Performance of Recycled Asphalt Shingles in Hot Mix Asphalt Sponsoring Agency – Missouri DOT Partners – CA, CO, IA, IN, MN, MO http://www.pooledfund.org/projectdetails.a sp?id=441&status=4
08/26/2009
Recycling Asphalt Shingles into Asphalt Pavements Kent R. Hansen, P.E.
16
RAS Summary Shingles are too valuable to throw away. Use manufacturers’ waste if available Tear-offs – Work with roofers to get clean material. – Work with local agencies on sampling plan
Performance – Improved rutting resistance – Reduced temperature susceptibility – Minimum affect on cold temperature properties 08/26/2009
Recycling Asphalt Shingles into Asphalt Pavements Kent R. Hansen, P.E.
17
RAS Summary (cont) Mix AC Content – Will reduce the amount of new asphalt required – Total asphalt contents often higher (0.2-0.4%)
Plant production – Similar to RAP
Mix design – Similar to RAP
Construction – Use conventional equipment – Some contractors report easier density 08/26/2009
Recycling Asphalt Shingles into Asphalt Pavements Kent R. Hansen, P.E.
18
www.morerap.us
What is WMA? Allows a reduction in the temperatures at which asphalt mixes are produced and placed.
nd 2
International WMA Conference
550 persons 24 countries
Warm-Mix Asphalt
RAP/RAS/WMA Survey RAP Total Estimated Tons Million Year Tons Accepted Tons use in HMA/WMA Tons used in Aggregate Tons used in Cold Mix Tons used in Other Tons Landfilled Avg. RAP %
2009
2010 67.2 56.1 6.2 1.5 0.7 0.1 16.2
73.5 62.1 7.3 1.6 0.8 0.004 18.0
RAP/RAS/WMA Survey RAS Companies/branches reporting using RAS Tons Accepted
Tons use in HMA/WMA Tons used in Aggregate Tons used in Cold Mix Tons used in Other Tons Landfilled
57% increase
Total Estimated Tons Thousand 2009 2010 44 61
957 701 6 123 -
1,851 1,099 3 124 6
RAP/RAS/WMA Survey WMA
Companies/branches reporting using WMA DOT Other Agency Commercial & Residential Total
Estimated Total Tons, million 2009 2010 85 121
Percent increase = 148%
10.7 3.7 4.8 19.2
25.8 10.1 11.7 47.6
www.store.asphaltpavement.org Pavement evaluation and project selection Materials and Mix Design Construction & Quality Control Performance
FG
4. D 75 FG D 9.5 FG 12 D .5 FG SM 19 A SM 9.5 A 1 SM 2.5 A O 19. 0 G FC O 9. G FC 5 12 . D CG 5 9. D CG 5 D 12. CG 5 19 .O
D
Min Lift Thick Range, mm
Recommended Mix Types Surface Courses Low Traffic Medium Traffic High Traffic
80 70 60 50 40 30 20 10 0
Mix Type
States increasing RAP use
States that have experimented with or routinely use high RAP mixtures
High RAP Performance The performance and life of pavement containing up to 30 percent RAP is similar to virgin pavements with no RAP. A survey of LTPP sections containing at least 30 percent RAP showed similar performance to virgin sections.
The Value of Milling
• Removes cracked and aged pavement surface • Improves pavement smoothness • Maintains curb height, drainage inlets, and bridge clearances • Improves bond with overlay Ref: Randy West, NCAT 3/30/2010
11
Using RAP to Maximize Your Pavement Dollar Kent Hansen, P.E.
RAS Why use asphalt shingles in asphalt pavement?
All materials commonly used in asphalt pavements
Sources Manufactures’ waste – Limited ~1 MT annual – Not in every state
Tear-offs – ~10 MT annual – Everywhere? State regulations Processors
08/26/2009
Recycling Asphalt Shingles into Asphalt Pavements Kent R. Hansen, P.E.
14
States Allowing RAS in Asphalt Mixes
08/26/2009
15
Pooled Fund Study TPF-5(213) Performance of Recycled Asphalt Shingles in Hot Mix Asphalt Sponsoring Agency – Missouri DOT Partners – CA, CO, IA, IN, MN, MO http://www.pooledfund.org/projectdetails.a sp?id=441&status=4
08/26/2009
Recycling Asphalt Shingles into Asphalt Pavements Kent R. Hansen, P.E.
16
RAS Summary Shingles are too valuable to throw away. Use manufacturers’ waste if available Tear-offs – Work with roofers to get clean material. – Work with local agencies on sampling plan
Performance – Improved rutting resistance – Reduced temperature susceptibility – Minimum affect on cold temperature properties 08/26/2009
Recycling Asphalt Shingles into Asphalt Pavements Kent R. Hansen, P.E.
17
RAS Summary (cont) Mix AC Content – Will reduce the amount of new asphalt required – Total asphalt contents often higher (0.2-0.4%)
Plant production – Similar to RAP
Mix design – Similar to RAP
Construction – Use conventional equipment – Some contractors report easier density 08/26/2009
Recycling Asphalt Shingles into Asphalt Pavements Kent R. Hansen, P.E.
18
www.morerap.us
What is WMA? Allows a reduction in the temperatures at which asphalt mixes are produced and placed.
nd 2
International WMA Conference
550 persons 24 countries
Warm-Mix Asphalt
RAP/RAS/WMA Survey RAP Total Estimated Tons Million Year Tons Accepted Tons use in HMA/WMA Tons used in Aggregate Tons used in Cold Mix Tons used in Other Tons Landfilled Avg. RAP %
2009
2010 67.2 56.1 6.2 1.5 0.7 0.1 16.2
73.5 62.1 7.3 1.6 0.8 0.004 18.0
RAP/RAS/WMA Survey RAS Companies/branches reporting using RAS Tons Accepted
Tons use in HMA/WMA Tons used in Aggregate Tons used in Cold Mix Tons used in Other Tons Landfilled
57% increase
Total Estimated Tons Thousand 2009 2010 44 61
957 701 6 123 -
1,851 1,099 3 124 6
RAP/RAS/WMA Survey WMA
Companies/branches reporting using WMA DOT Other Agency Commercial & Residential Total
Estimated Total Tons, million 2009 2010 85 121
Percent increase = 148%
10.7 3.7 4.8 19.2
25.8 10.1 11.7 47.6
