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Asphalt Pavement Association Of MichiganAsphalt Pavement Association Of Michigan
Selecting the Right MixSelecting the Right Mix
6639 Centurion Drive, Suite 1206639 Centurion Drive, Suite 120
Lansing, MI 48917Lansing, MI 48917
517517--323323--7800 5177800 517--323323--6505 (Fax)6505 (Fax)
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Asphalt Pavement Association Of MichiganAsphalt Pavement Association Of Michigan
Selecting the Right MixSelecting the Right Mix
� History
� Performance Graded Binders
� NAPA Guide
� MDOT Guide
� Local Agency Guide
� Mixes Generally Used
� Other Considerations
OutlineOutline
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Asphalt Pavement Association Of MichiganAsphalt Pavement Association Of Michigan
Selecting the Right MixSelecting the Right Mix
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Asphalt Pavement Association Of MichiganAsphalt Pavement Association Of Michigan
Selecting the Right MixSelecting the Right Mix
From B
ike pat
h...
From B
ike pat
h...
...to L
ocal Ro
ad
...to L
ocal Ro
ad
…to In
tersta
te
…to In
tersta
te
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Asphalt Pavement Association Of MichiganAsphalt Pavement Association Of Michigan
Selecting the Right MixSelecting the Right Mix
For each there are:For each there are:
� Right mixes
Wrong mixesWrong mixes
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Asphalt Pavement Association Of MichiganAsphalt Pavement Association Of Michigan
Selecting the Right MixSelecting the Right Mix
Mix History
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Asphalt Pavement Association Of MichiganAsphalt Pavement Association Of Michigan
Selecting the Right MixSelecting the Right Mix
Asphalt Mix History
1970’s
� 4.11 Bituminous Aggregate Pavement
� 4.12 9A Binder
� 25A Leveling/Wearing
� 31A Wearing
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Asphalt Pavement Association Of MichiganAsphalt Pavement Association Of Michigan
Selecting the Right MixSelecting the Right Mix
� #500 & #700 20C Bases
� #1100 L & T 20A, 20AA
� #1300, #1500, #1800 L &T 20AA
Stability Mixes
1980’s
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Asphalt Pavement Association Of MichiganAsphalt Pavement Association Of Michigan
Selecting the Right MixSelecting the Right Mix
� 2B, 2C Bases
� 3B, 3C Leveling
� 4B, 4C Top
� 11A Base, Leveling,
� 13, 13A Base, Leveling, Top
� 36A, 36B Leveling, Top
Performance Mixes
1990’s
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Asphalt Pavement Association Of MichiganAsphalt Pavement Association Of Michigan
Selecting the Right MixSelecting the Right Mix
� E03, E1, E3, E10, E30, E50
� 2EO3 thru 5E50
SuperPave Mixes
2000’s
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Asphalt Pavement Association Of MichiganAsphalt Pavement Association Of Michigan
Selecting the Right MixSelecting the Right Mix
Asphalt Cement History
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Asphalt Pavement Association Of MichiganAsphalt Pavement Association Of Michigan
Selecting the Right MixSelecting the Right Mix
� Penetration Grades – 1920’s
85-100
120-150
200-300
� Viscosity Grades – 1960’s
AC-2.5
AC-5
AC-10
� PG Binders: Mid 90’s
PG 58-28
Asphalt Cement History
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Asphalt Pavement Association Of MichiganAsphalt Pavement Association Of Michigan
Selecting the Right MixSelecting the Right Mix
Performance Graded Binders
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SUPERPAVE SUPERPAVE
Performance Grade (PG)Performance Grade (PG)
Binder SpecificationBinder Specification
� Fundamental properties related to pavement
performance
� Environmental factors
� In-service & construction temperatures
� Short and long term aging
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PG SpecificationsPG Specifications
� Based on rheological testing
– Rheology: study of flow and deformation
� Asphalt cement is a viscoelastic material
� Behavior depends on:
– Temperature
– Time of loading
– Aging (properties change with time)
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Superpave Asphalt Binder SpecificationSuperpave Asphalt Binder Specification
The grading system is based on climate
PG 64 - 22
Performance
Grade
Average 7-day max
pavement temperature
Min pavement
temperature
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Developed from Air TemperaturesDeveloped from Air Temperatures
� Superpave Weather Database
– 6500 stations in U.S.
andhttp://www.ltppbind.com/ Canada
� Annual air temperatures
– hottest seven-day temp (avg and std dev)
– coldest temp (avg and std dev)
� Calculated pavement temps used in PG
selection
> 20 years
SHRPA-648A
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Convert to Pavement TemperatureConvert to Pavement Temperature
• Calculated by Superpave software
• High Temperature (20 mm below surface of mixture)
• Low Temperature (at surface of mix)
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Superpave Asphalt Binder SpecificationSuperpave Asphalt Binder Specification
The grading system is based on climate
PG 64 - 22
Performance
Grade
Average 7-day max
pavement temperature
Min pavement
temperature
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Binder Grade SelectionBinder Grade Selection
Grade varies with:
� Location/Environment
� Reliability
� Traffic level
� Traffic speed
� Depth in Pavement Structure
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Binder Grade SelectionBinder Grade Selection
Resources:
� Published Guides
– MDOT HMA Mixture Selection Guidelines
– Local Agency HMA Selection Guidelines
� LTTPBind Software
– http://www.ltppbind.com
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What Binders are Used in MichiganWhat Binders are Used in Michigan
� 76-28P
� 70-22P, 70-28P
� 64-28, 64-34P
� 64-22
� 58-28
� 58-22, 58-34
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““Rule of 90Rule of 90””Effect of Loading Rate
Effect of Loading Rate
Effect of Traffic
Effect of TrafficRounding
Rounding
Reliability
Reliability
Example: PG 64 Example: PG 64 -- 34 has a temperature 34 has a temperature
range of 64 to range of 64 to -- 34 or 98 C. Therefore, this 34 or 98 C. Therefore, this
binder is probably modified !! binder is probably modified !! (Depends on (Depends on
Asphalt Source!)Asphalt Source!)
Is a PG a Modified Is a PG a Modified Binder ?Binder ?
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Binder Grade vs. Pavement Performance Binder Grade vs. Pavement Performance
Other Performance Factors:
• Rutting - shear strength of mix, aggregate properties
• Fatigue Cracking - pavement structure, traffic
Important Factor:
• Low temperature Cracking – correlates well to binder properties
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Asphalt Pavement Association Of MichiganAsphalt Pavement Association Of Michigan
Selecting the Right MixSelecting the Right Mix
NAPA Guide
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Asphalt Pavement Association Of MichiganAsphalt Pavement Association Of Michigan
Selecting the Right MixSelecting the Right Mix
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Asphalt Pavement Association Of MichiganAsphalt Pavement Association Of Michigan
Selecting the Right MixSelecting the Right Mix
WhatWhat’’s in the Guides in the Guide
� Pavement layers and traffic level definitions
� General surface preparation recommendations
� Mix Types
– Definitions
– Purpose
– Materials
� Procedure for selecting mixes
� Examples
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Asphalt Pavement Association Of MichiganAsphalt Pavement Association Of Michigan
Selecting the Right MixSelecting the Right Mix
Local Agency Guide
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Asphalt Pavement Association Of MichiganAsphalt Pavement Association Of Michigan
Selecting the Right MixSelecting the Right Mix
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Asphalt Pavement Association Of MichiganAsphalt Pavement Association Of Michigan
Selecting the Right MixSelecting the Right Mix
Local Agency ProgramsLocal Agency Programs
HMA Selection GuidelinesHMA Selection Guidelines
� Developed for use on Local Agency Projects
� Reviewed and Approved by CRAM
� Variations Allowed
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Asphalt Pavement Association Of MichiganAsphalt Pavement Association Of Michigan
Selecting the Right MixSelecting the Right Mix
Local Agency ProgramsLocal Agency Programs
HMA Selection GuidelinesHMA Selection Guidelines
� SuperPave and Marshall mix designs
� SuperPave for Commercial ADT > 700
� Variations Allowed
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Asphalt Pavement Association Of MichiganAsphalt Pavement Association Of Michigan
Selecting the Right MixSelecting the Right Mix
Local Agency ProgramsLocal Agency Programs
HMA Selection GuidelinesHMA Selection Guidelines
� Selection based on Present Day two-way
commercial ADT
� Assumed future growth
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Asphalt Pavement Association Of MichiganAsphalt Pavement Association Of Michigan
Selecting the Right MixSelecting the Right Mix
Local Agency ProgramsLocal Agency Programs
HMA Selection GuidelinesHMA Selection Guidelines
3401 – 99991001 – 3400701 – 1000301 – 7000 – 300Commercial
ADT
3E303E103E32C13ABase
4E304E104E33C
4E1
13A or
LVSP
Leveling
5E30 or
5E10
5E10 or
4E10
5E3 or
4E3
4C
5E1
13A or 36A
or LVSP
Surface
Mixture Type
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Asphalt Pavement Association Of MichiganAsphalt Pavement Association Of Michigan
Selecting the Right MixSelecting the Right Mix
Local Agency ProgramsLocal Agency Programs
HMA Selection GuidelinesHMA Selection Guidelines
3401 – 99991001 – 3400701 – 1000301 – 7000 – 300Commercial
ADT
PG 70-28PPG 64-28PG 64-28PG 64-28PG 58-28All Other
PG 70-22PPG 64-22PG 64-22PG 64-22PG 58-22Metro
PG 58-34PG 58-34PG 58-34PG 58-34Superior
Binder Grades by Region
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Asphalt Pavement Association Of MichiganAsphalt Pavement Association Of Michigan
Selecting the Right MixSelecting the Right Mix
Local Agency ProgramsLocal Agency Programs
HMA Selection GuidelinesHMA Selection Guidelines
� Base Course Binder Selection
– Use PG 58-28 for Superior Region
– Use PG 58-22 for all other Regions
� A Base Course is defined as:
– All layers below 4” of the surface
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Asphalt Pavement Association Of MichiganAsphalt Pavement Association Of Michigan
Selecting the Right MixSelecting the Right Mix
Local Agency ProgramsLocal Agency Programs
HMA Selection GuidelinesHMA Selection Guidelines
� Target Air Voids
– Mixes are specified with 4% design AV
– Can be reduced to 3% for 13A and 36A mixes
� Add a note to the HMA Application Table
– Reduce shoulder mixes to 2.5% AV
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Asphalt Pavement Association Of MichiganAsphalt Pavement Association Of Michigan
Selecting the Right MixSelecting the Right Mix
Local Agency ProgramsLocal Agency Programs
HMA Selection GuidelinesHMA Selection Guidelines
� One Course Overlays
– Decrease cold temperature number of the PG
Binder by one grade
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Asphalt Pavement Association Of MichiganAsphalt Pavement Association Of Michigan
Selecting the Right MixSelecting the Right Mix
Local Agency ProgramsLocal Agency Programs
HMA Selection GuidelinesHMA Selection Guidelines
220275410275330500275165Max.
#/syd
165220330165220350165110Min.
#/syd
5E_4E_3E_4C3C2C13A36A
Superpave MixtureMarshall MixtureMixture
Type
Note: Application Rate of 110#/syd. Per 1 inch Thickness
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Asphalt Pavement Association Of MichiganAsphalt Pavement Association Of Michigan
Selecting the Right MixSelecting the Right Mix
Local Agency ProgramsLocal Agency Programs
HMA Selection GuidelinesHMA Selection Guidelines
� Aggregate Wear Index
– Specified for Surface course mixes
– Based on ADT (vehicular and commercial) per lane
260> 2000
220100 – 2000
None< 100
Minimum AWIADT/Lane
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Asphalt Pavement Association Of MichiganAsphalt Pavement Association Of Michigan
Selecting the Right MixSelecting the Right Mix
Other Considerations
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Asphalt Pavement Association Of MichiganAsphalt Pavement Association Of Michigan
Selecting the Right MixSelecting the Right Mix
� Proven Technology
� Proven Performance
� Economical
� Readily Available
Recycled Asphalt Pavement (RAP)
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Asphalt Pavement Association Of MichiganAsphalt Pavement Association Of Michigan
Selecting the Right MixSelecting the Right Mix
Binder Considerations
� Reduce added binder to account for RAP
binder
� For higher RAP contents, use softer virgin
binder grade
Recycled Asphalt Pavement (RAP)Mix Design Basics
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Asphalt Pavement Association Of MichiganAsphalt Pavement Association Of Michigan
Selecting the Right MixSelecting the Right Mix
� RAP percentage based on % of RAP binder
to total binder in the mix
� Depends on specific rap and % AC in mix
� Generally allows more RAP before
adjusting Binder grades
MDOT Practice for Using RAP
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Asphalt Pavement Association Of MichiganAsphalt Pavement Association Of Michigan
Selecting the Right MixSelecting the Right Mix
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Asphalt Pavement Association Of MichiganAsphalt Pavement Association Of Michigan
Selecting the Right MixSelecting the Right Mix
� 0 to 17 % RAP, no change in binder grade
– (approx 22 to 23 % RAP by total wt.)
� 18-27 % RAP,
– (approx 23 to 29 % RAP by total wt)
– lower binder grade by one increment
– PG 58-28 → PG 52-34, or 58-34
� More than 28%, use blending charts
– > 30 % RAP by total wt
MDOT Practice for Using RAP
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Asphalt Pavement Association Of MichiganAsphalt Pavement Association Of Michigan
Selecting the Right MixSelecting the Right Mix
Economics:
� Existing Pavement Condition
� Fix Life
� Low Temperature Cracking “Protection”
Binder Selection
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Asphalt Pavement Association Of MichiganAsphalt Pavement Association Of Michigan
Selecting the Right MixSelecting the Right Mix
Example:
� 1 ½” resurfacing of existing road
– 98% reliability binder grade is PG 58-34
� Consider using PG 58-28 ?
– Reflective cracking
Binder Selection
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Asphalt Pavement Association Of MichiganAsphalt Pavement Association Of Michigan
Selecting the Right MixSelecting the Right Mix
� In-place Density is Critical
– Initial In-place Air Voids <8%
� Lift Thickness Affects Compaction
– Consolidation “Room”
– Cooling Rate
Lift Thickness vs. Performance
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Asphalt Pavement Association Of MichiganAsphalt Pavement Association Of Michigan
Selecting the Right MixSelecting the Right Mix
Minimum Layer Thickness
� Fine Graded = 3 x Nominal Maximum
Aggregate Size (NMAS)
� Coarse Graded = 4 x NMAS
NCAT Recommendation for
SuperPave Mixes
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Asphalt Pavement Association Of MichiganAsphalt Pavement Association Of Michigan
Selecting the Right MixSelecting the Right Mix
� Determine Total Asphalt Thickness
� Select Surface Course Type
– NMAS
– Minimum Lift Thickness
– Repeat Process for remaining HMA layers
Mixture Selection Procedure
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Asphalt Pavement Association Of MichiganAsphalt Pavement Association Of Michigan
Selecting the Right MixSelecting the Right Mix
Binder Grade vs. Pavement PerformanceBinder Grade vs. Pavement Performance
Important Factor:
• Low temperature Cracking – correlates well to
binder properties
Other Factors:
• Rutting - shear strength of mix, aggregate
properties
• Fatigue Cracking - pavement structure, traffic
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Asphalt Pavement Association Of MichiganAsphalt Pavement Association Of Michigan
Selecting the Right MixSelecting the Right Mix
Questions?
www.apa-mi.org
517.323.7800 800.292.5959