joe peterson

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Presentation by Joe Peterson of Caltrans on the Caltrans move to "Superpave" delivered at the CalAPA Fall Asphalt Pavement Conference Oct. 24, 2013 in Sacramento, Calif.

TRANSCRIPT

California’s Transition Hveem To Superpave

Trivia

Pilot Projects• 6 Projects Completed• 13 Projects in Construction• 14 Approved Mix Designs• Placed over 100,000 tons of HMA-SP (Type A) and

RHMA-SP-G• Superpave HMA has been placed in high traffic

areas such as LA-405, and low volume country roads, all with great success.

o

Studies• University of California Pavement Research Study• Completed: December 2012• Looked at 15 Existing Hveem JMF’s from around

the State• Study showed all 15 mix designs with some

adjustments in OBC , grading and dust proportion would meet the Superpave specification.

• Report is available at:o http://www.dot.ca.gov/hq/esc/Translab/ormt/superpave/index.htm

Superpave MethodologyAASHTO M 323

Volumetric requirements

AASHTO R 35Mix Design evaluation

AASHTO T 312SGC Mixture Compaction

AASHTO R 30Mixture Conditioning

AASHTO T 324Hamburg Test

SP 2SUPERPAVE Mix Design Handbook

VolumetricsAir Voids, VMA, VFA

AASHTO T 283Moisture Sensitivity

Job MixFormula

JMF DESIG

N

Basis for Design• Gyrations Compaction AASHTO T 312

Type A RHMA-GNinitial 8 Ndesign =50-150Ndesign 85

Nmax 130

• Air Voids AASHTO T 269Type A RHMA-G

Ninitial >8.0% Ndesign=Specifications Ndesign =4.0%Nmax >2.0%

Design VolumetricsAsphalt Institute SP-2

HMA Type A-SP• VMA

o 1/4” grading 18.0 (-1.0, +3.0)o 3/8” grading 16.0 (-1.0, +3.0)o 1/2” grading 14.5 (-1.0, +3.0)o 3/4” grading 13.5 (-1.0, +3.0)

• DPo 1/4” & 3/8” grading 0.6-1.3o 1/2” & 3/4” grading 0.6-1.3o 1” grading 0.6-1.3

DesignVolumetricsAsphalt Institute SP-2

RHMA G-SP• VMA

o 1/2” grading 19.0-24.0o 3/4” grading 19.0-24.0

• DPo All grading’s Report Only

Hamburg Wheel TrackerAASHTO T324

Testing Temperatureso PG 58 45 degrees C o PG 64 50 degrees Co PG 70 + 55 degrees C

Hamburg Wheel TrackerAASHTO T324

HMA Type A-SP

• Maximum 1/2” Ruttingo PG 58 10,000 passeso PG 64 15,000 passeso PG 70 20,000 passeso PG 76 (+) 25,000 passes

• Inflection pointo PG 58 10,000 passeso PG 64 10,000 passeso PG 70 12,500 passeso PG 76 (+) 15,000 passes

Hamburg Wheel TrackerAASHTO T324

RHMAG-SP

• Maximum 1/2” Ruttingo PG 58 15,000 passeso PG 64 20,000 passeso PG 70 25,000 passes

• Inflection pointo PG 58 10,000 passeso PG 64 10,000 passeso PG 70 12,500 passes

Inflection Point Defined

Moisture Sensitivity AASHTO T283

HMA Type A-SP & RHMA-G-SP• Minimum Dry Strength Break

o 100 psi 4” or 6” sample (gyratory)• Minimum Wet Strength Break

o 70 psi 4” or 6” sample (gyratory) • Ratio is no longer measured• Testing done on plant produced material

CRUSHED/FRACTUREDFACES

AASHTO T335* • Percent of crushed particles Type A RHMA

Coarse aggregate (% min.)One fractured face 95 --- Two fractured faces 90

90

Fine aggregate (% min) 70 70

(Passing No. 4 sieveand retained on No. 8 sieve.

*Crushed Face defined as 50% of projected face

RAP Utilization• JMF Design: RAP

o0% to 25% o RAP fractionated into:• + #3/8” Sieve• - #3/8” Sieve

oAllowable stockpile variance, binder content: +/-2.0%

oRice Specific Gravity• Allowable stockpile variance Gmm= +/-0.060

Binder Content/Air Voids

Plant Produced Material• Asphalt Binder Content %

HMA Type A-SP RHMA G-SP

- 0.30, +0.5 - 0.40, +0.5

• Air Voids Content %HMA Type A-SP RHMA G-SP 4 +/- 1.5 Specification +/- 1.5

*Bulk SPG by Weigh wax weigh

PRODUCTION

PARAMETERS

Production QC and QA• Aggregate Quality• Aggregate Grading• Binder Content• HMA Moisture• VMA, DP, & Air voids• Hamburg Wheel Tracker• Moisture Susceptibility

Density QC• Percent of theoretical maximum

density by Nuclear gauge (%) HMA Type A-SP RHMA G-SP 92 – 97 92 – 97

Verify gauge correlation to cores every 10,000 tons utilizing the average of 2 cores

Density QC• Percent of theoretical maximum density

by coreo 2 per paving day

HMA Type A-SP RHMA G-SP 92 – 97 92 – 97

Verify gauge correlation to cores every 10,000 tons utilizing the average of 2 cores

Minor Hot Mix Asphalt• 1000 tons or less total production for:

o Caltrans Projectso Projects within State Right-A-Way

• Requires a JMF submittal• Mandatory use of liquid antistrip• Requires a production start up

evaluation • Requires quality control testing

Minor Hot Mix Asphalt• Verification is done on laboratory

produced material (No hot drop)• Verifications times remain the same• AASHTO T 324 does not apply• AASHTO T 283 does not apply• CT 204 does not apply• FAA and F&E do not apply

Minor Hot Mix Asphalt• Verification consists of testing

for:oAggregate qualityoAggregate gradationoAsphalt binder contentoAir VoidsoVMA

Minor Hot Mix Asphalt• QC testing consists of:

oAggregate gradationoAsphalt binder contentoAir VoidsoVMAoDensity by Nuclear gage (if applicable)

Minor Hot Mix Asphalt• QA consists of testing for:

oAggregate gradationoAsphalt binder contentoAir VoidsoVMA

Quality HMA

Mix Design

sampling

QC

QA

QUESTIONS?

?

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