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SUPERPAVESUperior PERforming Asphalt PAVEments
History of Hveem Mix Design
Hveem mix design was created by Francis Hveem in the 1920’s
Basic premise of the design methodology is to coat each aggregate particle with an optimal amount of binder.
Methodology updated by Hveem in the 1950’s to account for traffic loadings.
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Mix design based on 1950’s traffic loading
Limitations of Hveem Mix Design
Todays Traffic Loading
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Limitations of Hveem Mix Design
Does not take into account: Weather/Environmental conditions
Binder properties PG grading
Polymer Modified
Rubber
Changing quality of aggregates
New testing criteria
Why Change
Traffic volumes and loading have skyrocketed
Axle configurations have changed
Super single
Increased tire pressure (pizza cutters)
Quality aggregate sources are dwindling
PG Binder grading
Mechanistic Empirical design
HMA volumetrics
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Why Change
Testing equipment availability
Hveem Compactors
Stabilometers
Why Change
Old dry pavementOld dry pavement
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Why Change
RuttingRutting
Why Change
ffiTraffic
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Implementation planTime Line
2012
Implement approximately 6 pilot projects
Revise Superpave specification
Implement 12 to 16 pilot projects2013
Revise Superpave specification
2014 Full implementation
Immediate ImpactsCities and Counties
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Current Project ListDistrict EA County/Route PM Est. Ad Date Est. Bid Open By
04 3E4401 CC‐580 0.0/5.8 RTL 1/13 Bid Pkg
Superpave Pilot ProjectsTons/Type
40,000 RHMA; 500 HMA
04 0A5344 Sol‐80 11.3/12.9 RTL 1/13 Bid Pkg
04 2G5104 CC‐4 31.1/32.4 RTL 1/13 Bid Pkg
04 229101 CC‐680 10.5/15.1 RTL 1/13 Bid Pkg
04 0A0801 CC‐80 3.8/5.3 RTL 10/12 Bid Pkg
05 0161E4 Mon‐101 In Construction CCO
06 430701 Tul‐216 1.9/2.9 8/1/2012 9/1/12 Bid Pkg
07 3Y3001 LA‐405 16.4/19.4 In Construction Bid Pkg
07 3Y9401 LA 110 20 1/30 5 I C i Bid Pk
12,530 RHMA; 33920 HMA
3,490 RHMA; 10,480 HMA
3,160 RHMA; 22,000 HMA
1265 RHMA; 19025 HMA
50,000 HMA Type A
14,000 HMA Type A
9,280 RHMA‐G
5 200 RHMA G WMA LSM07 3Y9401 LA‐110 20.1/30.5 In Constuction Bid Pkg
07 25200 LA‐405 34.3/48.6 9/1/2012 11/1/12 Bid Pkg
08 0K2300 SBd‐10 44.0/R53.0 9/3/2012 Bid Pkg
08 0P8601 SBd‐10 R57.6/R60.9 02/15/13 Bid Pkg
09 351601 INY‐39545‐5‐50.3 NB50.9‐52.9 RTL 1/13 Bid Pkg
10 0M8004 Tul‐99 30.9/38.7 Complete 8/1/12 CCO
11 27520 Imp‐98 21.8/31.3 1/3/12 4/1/12 Bid Pkg
5,200 RHMA‐G WMA LSM
25,200 RHMA‐G
9,940 RHMA‐G
36,000 RHMA‐G
20,000
31,247 HMA Type A
Superpave Equipment
Pine SGC Model AFG2A
Troxler SGC Model 4140
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Superpave Equipment
Hamburg Wheel Tracker (HWT)Inside View
Hamburg Wheel Tracker (HWT)
Overview
Pilot projects will be “Standard Process”
Caltrans material testers will be using National Standards (AASHTO/ASTM)
Independent Assurance will be testing and witnessing field and lab material testers
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Superpave and the Caltrans IA Program
Effects to the IA Program No change in current requirements in: Accrediting laboratories
Certifying Technicians
Change in IA practice: Familiarize with both AASHTO and CT Test Methods
“Grandfather” AASHTO with equivalent CT Test Grandfather AASHTO with equivalent CT Test
Certification CTM = Certificate of Proficiency (TL-0111)
AASHTO = “witness” statement (development stage)
SuperpaveAASHTO/ASTM vs CTM
AASHTO/ASTM
Description(Aggregate Tests)
CTMGrandfatherYes No
T 11Materials Finer Than 75-μm (No. 200) Sieve in Mineral Aggregates by Washing
201, 202
T 27 Sieve Analysis of Fine and Coarse Aggregates 201, 202
T 30 Mechanical Analysis of Extracted Aggregate 201, 202
T 335 Determining the Percentage of Fracture in Coarse Aggregate 205
T 84 Specific Gravity and Absorption of Fine Aggregate 207
T85 Specific Gravity and Absorption of Coarse Aggregate 206
T 176Plastic Fines in Graded Aggregates and Soils by Use of the Sand Equivalent Test
217
T 304 Uncompacted Void Content of Fine Aggregate 234
D 4791Flat Particles, Elongated Particles, or Flat and Elongated Particles in Coarse Aggregate1
235
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SuperpaveAASHTO/ASTM vs CTM
AASHTO/ DescriptionCTM
GrandfatherASTM
p(Mix Test)
CTMYes No
T 209Theoretical Maximum Specific Gravity and Density of Hot Mix Asphalt (HMA)
309
T 269Percent Air Voids in Compacted Dense and Open Asphalt Mixtures
308, 309
T 275Bulk Specific Gravity of Compacted Hot Mix Asphalt (HMA) Using Paraffin-Coated Specimens
308
T 283Resistance of Compacted Hot Mix Asphalt (HMA) to Moisture-Induced Damage
371
T 308Determining the Asphalt Binder Content of Hot Mix Asphalt (HMA)
367 T 308by the Ignition Method
367
T 312Preparing and Determining the Density of Hot Mix Asphalt (HMA) Specimens by Means of the Superpave Gyratory Compactor
None
T 324Hamburg Wheel-Track Testing of Compacted Hot Mix Asphalt (HMA)
None
T 329 Moisture Content of Hot Mix Asphalt (HMA) by Oven Method 370
SuperpaveNew Test Methods
AASHTO M 323Volumetric requirements
AASHTO R 35Mix Design evaluation
AASHTO R 30Mixture Conditioning
SP 2SUPERPAVE
Mix Design Handbook
AASHTO T 312SGC Mixture Compaction
g
AASHTO T 324Hamburg Test
VolumetricsAir Voids, VMA, VFA
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SuperpaveLaboratory Accreditation
Current requirements from IA Manual still apply Participation in Caltrans’ RSP Submittal of CLAM Laboratory inspectionLaboratory inspection
New requirements AMRL Participation AASHTO accreditation
SuperpaveLaboratory Equipment
Calibration Requirements for SGC and HWT Annual Calibration
Calibration performed by Manufacturer
O O t id Or Outside company
Calibration verification Performed by Caltrans IA
Laboratory Staff
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Specification Changes
JMF Development:
New Forms: 3511SP 3512 SP 3513SP Forms can be found at:
http://www.dot.ca.gov/hq/esc/Translab/ofpm/superpave/index.htm
OBC is specified by “Total Weight of Mix” OBC is specified by Total Weight of MixWork sheets are available at http://www.dot.ca.gov/hq/esc/Translab/ofpm/superpave/index.htm
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Specification Changes
JMF Design: Aggregate AASHTO T335 CT205
Percent of crushed particles HMA‐SP RHMA‐SP OGFCCoarse aggregate (% min.)
One fractured face 95 90 90
Two fractured faces 90 90 90
Fine aggregate (% min)
(Passing No. 4 sieve
and retained on No. 8 sieve.)
Two fractured faces 70 70 90
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Specification Changes
JMF Design: Aggregate
Los Angeles Rattler (% Max loss) AASHTO T69 CT211
Sand Equivalent AASHTO T176 CT217
Average of 3 tests from same sample
FAA AASHTO T FAA AASHTO T304 ‐‐‐‐‐‐‐
Flat and Elongated ASTM D4791 ‐‐‐‐‐‐‐
Specification Changes
JMF Design: RAP 25% +/‐ 1% at JMF Design, +/‐3% during producti0n RAP fractionated into:
+ #4 Sieve
‐ #4 Sievell bl k l b d / Allowable stockpile variance, binder content: +/‐2.0%
Sieve correction factors & binder content Binder content* ASTM 2172 ‐‐‐‐‐
Grading RAP ‐‐‐‐ CT 202
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Specification Changes
JMF Design: RAP Rice Specific Gravity AASHTO T209 CT309
Allowable stockpile variance Gmm= +/‐0.060
Ignition oven* AASHTO T309 CT382
* Requires 3 samples
Specification Changes
JMF Design: RAP
HMA mixtures with RAP
Maximum binder replacement is 25.0 percent for surface course and 40.0 percent for lower courses.
Surface course is defined as the upper most 0.2 feet pp
HMA with a binder replacement percent less than or equal to 25% of OBC , you may bump down 1 grade.
HMA with a binder replacement greater than 25% and less than or equal to 40% OBC, mandatory bump down 1 grade
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Specification Changes
JMF Design
All laboratories performing any part of HMA mix designs must be qualified under AMRL, and CT Independent Assurance program
HMA & RHMA mix design AASHTO R35 CT367HMA & RHMA mix design AASHTO R35 CT367
AASHTO M323 does not apply
OGFC ‐‐‐‐‐‐‐ CT368
Mix Design performed by Caltrans
Specification Changes
JMF Design: OBC Gyrations Compaction AASHTO T 312 CT367 HMA‐SP RHMA‐SP‐G
Ninitial =8 Ndesign =50‐150
Ndesign =85
Nmax =130
Air Voids (+/‐ 0.5%) AASHTO T 269 HMA‐SP RHMA‐SP‐G
Ninitial =8.0% Ndesign =Specifications
Ndesign =4.0%
Nmax =2.0%
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Specification Changes
JMF Design: Volumetrics
VMA SP‐2 LP‐2Grading Type‐A RHMA‐SP‐G
No. 4 18 ‐‐‐‐‐‐‐‐
3/8” 16.0 ‐‐‐‐‐‐‐‐3/8 16.0
½” 14.5 19.0 ‐ 24.0
¾” 13.5 19.0 ‐ 24.0
Specification Changes
JMF Design: Volumetrics
VFA SP‐2 LP‐3Grading Type‐A RHMA‐SP‐G
No. 4 65‐75 Report Only
3/8” 65‐75 Report Only3/8 65 75 Report Only
½” 65‐75 Report Only
¾” 65‐75 Report Only
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Specification Changes
JMF Design: Volumetrics
Dust Proportion SP‐2 LP‐4Grading Type‐A RHMA‐SP‐G
No. 4 and 3/8” 0.9‐2.0 Report Only
1/2" and ¾” 0.6‐1.3 Report Only/ 3 p y
Specification Changes
JMF Design:
Moisture sensitivity/rutting/raveling AASHTO T324
Plant produced material Maximum rutting depth: 0.5”
Binder Grade Type‐A RHMA‐SP‐Gyp
PG 58 10,000 15,000
PG 64 15,000 20,000
PG 70 20,000 25,000
PG 76 25,000 ‐‐‐‐‐‐‐‐‐‐‐
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Specification Changes
Moisture sensitivity/rutting/raveling AASHTO T324
10,000 passes minimum for inflection pointinflection point
JMF Design:
Specification Changes
JMF Design:
Moisture Susceptibility AASHTO T 283 CT371
Plant produced material
Minimum dry strength 120 psi
Minimum TSR 70%
Gyratory prepared samples 4” or 6” specimens
Freeze/Thaw conditioning is optional
Required for HMA –SP & RHMA‐SP‐G
You Must meet both
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Specification Changes
JMF Design:
For RHMA‐SP‐G you may increase SGC pressure to a maximum of 825 Kpa (120 psi)
For RHMA‐SP‐G you may hold specimen at constant height for a maximum of 90 minutesg 9
Specification Changes
JMF Verification: “For JMF verification, use the optimum binder content specified on your CEM‐3512SP, no adjustments are allowed”.
“When RAP is used, binder set point for HMA must be the optimum binder content specified on the CEM‐3512SP optimum binder content specified on the CEM 3512SP minus the percent RAP multiplied by the combined average binder content of the processed fractionated RAP stockpiles”.
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JMF Verification:
Specification Changes
For VMA, VFA and DP, HWT & T283: Testing is on Plant Produced Material HMA quality specified in the table titled "Hot Mix Asphalt Mix Design Requirements”
Binder Content (HMA ± 0.30 percent, RHMA ± 0.40 percent)
Air voids content (design value ± 1 5 percent) Air voids content (design value ± 1.5 percent)
Void in Mineral Aggregate (13.5+3/‐1) for ¾” Grading
Voids filled with asphalt (design value +/‐ 1.0 percent)
Dust proportion (design value +/‐ 0.5)
Specification Changes
JMF Verification:
The State will verify up to 2 proposed JMF’s for each binder and aggregate specified.
Each additional verification will cost $3000. (Engineers option)(Engineers option)
The Engineer will verify 1 binder source change per approved JMF. The cost will be $2000
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Specification Changes
JMF Verification:
If you do not verify you may: Change Asphalt binder content target value up to ±0.2 percent from the optimum binder content.
For RHMA‐SP‐G, OBC may not be below 7.5 by TWM
Change aggregate target values, but must be within target value limits
Specification Changes
Construction: Quality Control Requirements
Percent of theoretical maximum density (%) by core
CT 375: 2 per paving day minimum
Type‐A RHMA‐SP‐G
92 – 97 92 – 97
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Specification Changes
Construction: Quality Control Requirements
Percent of theoretical maximum density by Nuclear gauge (%)
CT 375: 3 per 250 tons but not less than 3 per paving day pa g day
Type‐A RHMA‐SP‐G
92 – 97 92 – 97Verify gauge correlation to cores every
10,000 tons utilizing the average of 2 cores
Specification Changes
Construction: Quality Control Requirements Hamburg Wheel Test
AASHTO T324: One per 10,000 tons or 1 per project whichever is more
Maximum rutting depth: 0.5”/Minimum inflection point: 10,000Binder Grade Type A RHMA SP GBinder Grade Type‐A RHMA‐SP‐G
PG 58 10,000 15,000
PG 64 15,000 20,000
PG 70 20,000 25,000
PG 76 25,000 ‐‐‐‐‐‐‐‐‐‐‐
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Specification Changes
Construction: Quality Control Requirements
Moisture Susceptibility
AASHTO T283: One per 10,000 tons or 1 per project whichever is more
Minimum dry strength 120 psi Minimum dry strength 120 psi
Minimum TSR 70%
Required for HMA –SP & RHMA‐SP‐G
Specification Changes on the Horizon
Expanded definition of “Commercial Mix”
Limit tonnage placed to about 5,000 tons or 2days paving.
l f d Require simplified JMF requirements
Grading/OBC
Hamburg
Volumetrics
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Specification Changes on the Horizon
Require Limited Production Testing
Grading
Binder content
Hamburg Wheel
Quality HMA
Mix Design
samplingQA
HMA
QC
