SHRP Superpave Today - Purdue Universityspave/old/Technical... · SHRP ASPHALT INSTITUTE Asphalt...

A A

S H

T O F H

W A

I N D U S T R YSUPERPAVE 2005

SHRP

ASPHALT INSTITUTE

AsphaltAsphaltUU--P GroupsP Groups

SuperpaveSuperpave® ® TodayTodayStatusStatus

ChallengesChallengesOur FutureOur Future

Thomas HarmanThomas HarmanMaterials & Construction Team Leader, R&DMaterials & Construction Team Leader, R&D

Federal Highway AdministrationFederal Highway Administrationwww.TFHRC.govwww.TFHRC.gov

AcknowledgementsAcknowledgements

Thanks to…Thanks to…

ONGOING ONGOING RefinementRefinement

•• Understanding modifiersUnderstanding modifiers•• Understanding acidUnderstanding acid•• Improved moisture testImproved moisture test•• Construction qualityConstruction quality•• Link to pavement designLink to pavement design•• Communication! Communication!

CHALLENGES

Paul MackPaul MackNew York State New York State -- RetiredRetired

Imperfection should never stall implementation.

You can still drink from a chipped cup.

A A

S H

T O F H

W A

I N D U S T R YSUPERPAVE 2005

Question is, “What kind of cup Question is, “What kind of cup do we have?”do we have?”

SuperpaveSuperpave®® Plus 2002Plus 200230% of DOT’s (5 Plus Methods)30% of DOT’s (5 Plus Methods)

•• Elastic recoveryElastic recovery•• Forced ductilityForced ductility•• Toughness and tenacityToughness and tenacity•• Phase anglePhase angle•• Method Method

(mode and dose)(mode and dose)•• CombinationsCombinations

0

10

20

30

40

50

As is Plus Spec.’s

PG Grade Specifications

Num

ber

of S

tate

s14

SHRP Asphalt SHRP Asphalt Program CoordinatorProgram Coordinator

“One of the principal goals of the SHRP asphalt program is to reduce or eliminate the

proliferation of asphalt binder specifications.”

Dr. Thomas Kennedy

Association of Modified Association of Modified Asphalt ProducersAsphalt ProducersAMAPAMAP

Las VegasLas VegasFebruary, 2005

STATE: ARKANSAS MATERIALS: Re: Section 404, Design and Quality Control of Asphalt Mixtures

DATE: 2004 Web Address: www/ahtd.state.ar.us/contract/progcon/general/stdspecs.htm

Materials Engineer: Jerry Westerman Email Address: [email protected]

ASPHALT BINDER:

Description:

Shall comply with requirements of AASHTO M 320, Table 1, except Direct Tension requirements are deleted and shall be from sources that have executed a certification agreement with the Department.

PMA’s: PG 70-22 & PG 76-22 shall be straight run binders that are modified using SB, SBS or SBR

404.01 (b)

Exclusions: None , other than type of polymer modifier

Requirements by Performance Grade, PG (Common Grades)

PROPERTY

Test Method

AASHTO or Other 64-22 70-22 76-22

ORIGINAL:

Flash Point, °C T 48 230 min.

Rotational Viscosity, Pa s 135°C T 316 3.0 max.

Dynamic Shear, kPa (G* /sin , 10 rad./sec.)

1.0 min. T 315 At grade temperature

RTFOT RESIDUE:

Mass Loss, % T 240 1.0 max.

Dynamic Shear, kPa (G* /sin , 10 rad./sec.)

2.20 min. T 315 At grade temperature

PAV RESIDUE R 28 100°C; 20 hrs; 300 psi

Dynamic Shear, kPa (G* sin , 10 rad./sec.)

5,000 max. T 315 25°C 28°C 31°C

S, 300MPa Creep Stiffness

m Value, 0.300

T 313

-12°C

PG PLUS REQUIREMENTS: YES

ORIGINAL:

Elongation Recovery 25°C, % T 301 --- 40 50

Polymer Type -- No SBR, SB, SBS

Notes: 1. If Anti-Strip needed, a heat stable liquid anti-strip additive from QPL shall be added at the rate of 0.5 - 0.75% by weight of asphalt binder as determined by laboratory analysis.

AR Page 1of 1

February, 2005

Ken Ken GrzybowskiGrzybowskiPRI Asphalt Technologies, Inc.PRI Asphalt Technologies, Inc.Tampa, FLTampa, FL

Concerning TrendConcerning Trend

•• 34 States with Plus Specs (67%)34 States with Plus Specs (67%)

•• 13 States Straight M 32013 States Straight M 320

•• 21 Different Pluses21 Different Pluses

•• 4 Duel / Hybrid4 Duel / Hybrid

•• The Winner! The Winner! ––M 320 with 13 PlusesM 320 with 13 Pluses++++++++++++++++++++++++++

05

101520253035

Num

ber

of S

tate

s

As is M320 Plus Spec.'sPG Grade Specifications

20022005

0 5 10 15 20

Polymer Content

Recovered Properties

Chemical Modification

Resilience

Smoke Point

Spot Test

Kinematic Viscosity

Ductility

Absolute Viscosity

Penetration

Softening Point

DTT/BBR

DTT

Phase Angle

DSR

Force Ratio & Ductility

Toughness & Tenacity

Sieve

Solubility

Separation / Compatibility

Elastic Recovery – ORIGINAL

Elastic Recovery – RTFOT

Alkaline

Used Motor Oil

Acid

Air Blown / Oxidized

PRESCRIPTIONS

Number of States

PrescriptionsExclusionsElastomericsConventionalOthers

The MinusesThe Minuses

•• Mostly EmpiricalMostly Empirical•• Varied PurposesVaried Purposes•• Multiple Test Methods Multiple Test Methods

–– Elastic Recover has Elastic Recover has at least 9 methodsat least 9 methods

•• Inconsistent ParametersInconsistent Parameters–– SBR SBR vsvs SBSSBS

The MinusesThe Minuses

•• Increased CostsIncreased Costs–– QC/QA TestingQC/QA Testing

•• Logistical Nightmare for Suppliers!Logistical Nightmare for Suppliers!

The PlussesThe Plusses

•• Great for PRI Asphalt Technologies.Great for PRI Asphalt Technologies.

ACTION ITEMSACTION ITEMS

•• We need regional coordination of We need regional coordination of Superpave Plus specificationsSuperpave Plus specifications

HighHigh--Temperature PerformanceTemperature PerformanceII--80, Nevada80, Nevada

Same gradation Same gradation -- different binders.different binders.

PG 63-22 modified No rutting

PG 67-22 unmodified 15mm of rutting

What do we need?What do we need?

•• Refinement to the Superpave binder Refinement to the Superpave binder purchase specificationpurchase specification to better to better capture the unique benefits of modified capture the unique benefits of modified systems (Step 2)systems (Step 2)

•• Better laboratory accelerated performance Better laboratory accelerated performance prediction toolsprediction tools to evaluate and to evaluate and characterize modified systems (Step 1)characterize modified systems (Step 1)

Purchase SpecificationPurchase Specification

•• Performance CriteriaPerformance Criteria–– Test Procedures, must be…Test Procedures, must be…

•• Easy to set upEasy to set up•• Easy to runEasy to run•• Easy to analyzeEasy to analyze

–– Test Procedures must be…Test Procedures must be…•• RepeatableRepeatable•• Reproducible Reproducible

Research ToolsResearch Tools

•• Performance Measure Performance Measure –– Test Procedures, can be…Test Procedures, can be…

•• Very difficult to set upVery difficult to set up•• Laborious to runLaborious to run•• Subject to interpretationSubject to interpretation

–– Test Procedures should be…Test Procedures should be…•• RepeatableRepeatable•• But not necessarily reproducible But not necessarily reproducible

Superpave® IISuperpave® IIBinder Purchase SpecificationBinder Purchase SpecificationPG PG –– based on degree daysbased on degree days

WHENWHEN WHATWHAT HOWHOW WHEREWHERE

ConstructionConstructionSafetySafety

PumpPump--abilityabilityRuttingRutting

Flash PointFlash PointRotational Rotational ViscVisc

DSR, JDSR, JNRNR

230230°° minmin3 Pa3 Pa--s maxs max

T(high)T(high)

EarlyEarly(RTFO or SAFT)(RTFO or SAFT)

RuttingRutting JJNRNR T(high)T(high)

LateLate(PAV or SAFT)(PAV or SAFT)

FatigueFatigueLowLow--TempTemp

DSRDSRBBR,DT, ABCBBR,DT, ABC

T(T(intint))T(low)T(low)

SuperpaveSuperpave®® IIII

FullFull--Scale Accelerated Scale Accelerated Performance Testing for Performance Testing for

SuperpaveSuperpave®® andandStructural ValidationStructural Validation

TPFTPF--5(019)5(019)

Thomas HarmanThomas HarmanMaterials & Construction Team Materials & Construction Team


Total Research OrganizationTotal Research Organization

Superpave® Refinement

1993 1999 20032001

SHRP Validation-Laboratory-ALF 5 Binders2 Gradations

NCHRP 90-07-Laboratory

11 Binders1 Gradation

TPF-5(019)-ALF

7+ Binders2 Gradations

PG 67-80 Study-Laboratory

12 Binders1 Gradation

PartnersPartners

ALF TWG Meeting ALF TWG Meeting –– June 2005June 2005

TPFTPF--5(019) / SPR5(019) / SPR--2(174)2(174)State Pooled Fund ParticipantsState Pooled Fund Participants

TPF-5(019)

SPR-2(174)

ALF StudiesALF StudiesTPFTPF--5(019)5(019)SPRSPR--2(174)2(174)

Industry PartnersIndustry Partners

•• CitgoCitgo•• DowDow•• DupontDupont•• KochKoch•• ParamountParamount•• TexParTexPar, BTI, BTI•• TrifineryTrifinery, GCA, GCA•• TrumbullTrumbull•• Wright AsphaltWright Asphalt•• Martin Color Martin Color Fi

•• Bit MatBit Mat•• MathyMathy ConstructionConstruction•• Hot Mix IndustriesHot Mix Industries•• FNF ConstructionFNF Construction•• ConsulpavConsulpav•• Rubber Producers Assoc.Rubber Producers Assoc.•• ISSISS•• RTG RTG •• NAPANAPA

Fi

Collaborative Research PartnersCollaborative Research Partners

•• Asphalt InstituteAsphalt Institute•• National Center for Asphalt TechnologyNational Center for Asphalt Technology•• Western Research InstituteWestern Research Institute•• University of ArkansasUniversity of Arkansas•• Ohio UniversityOhio University•• Queens UniversityQueens University•• Arizona State UniversityArizona State University•• FWD Users GroupFWD Users Group

PTF/ALF EXPERIMENT 6PTF/ALF EXPERIMENT 6

DATA COLLECTION AND INSTRUMENTATIONDATA COLLECTION AND INSTRUMENTATION•• Laboratory TestingLaboratory Testing•• FWDFWD•• Strain GagesStrain Gages•• MultiMulti--Depth Depth DeflectometersDeflectometers•• Weather Station, Weather Station, TDRsTDRs, & Thermocouples, & Thermocouples•• Transverse ProfilingTransverse Profiling•• Crack MappingCrack Mapping

Current Completion DatesCurrent Completion Dates

•• Rutting testing Jan. 2004Rutting testing Jan. 2004•• Fatigue testing (100Fatigue testing (100--mm) Mar. 2006mm) Mar. 2006•• Fatigue testing (150Fatigue testing (150--mm) Dec. 2007mm) Dec. 2007

Two FHWA ALFs with Two FHWA ALFs with 12 Pavement Lanes Constructed in 12 Pavement Lanes Constructed in

the Summer and Fall of 2002the Summer and Fall of 2002

AsAs--Built Pavement Lanes Built Pavement Lanes

CR-AZ----70-22

1

PG70-22Control

2

AirBlown

3

SBSLG

4

CR-TB

5

TP

6

PG70-22

+Fibers

7

PG70-22

8

SBS64-40

9

AirBlown

10

SBSLG

11

TP

12

1 2

3 4

RuttingRuttingTThighhigh = 64= 64°°CC

FatigueFatigueTTintint = 19= 19°°CC

FatigueFatigueTTintint = 28= 28°°CC

ReplicateReplicate

ALF Testing

Rutting Test DataRutting Test Data

(64 (64 ooCC and 45 and 45 kNkN))

ALF HMA RuttingALF HMA RuttingHMA Layer Rutting for All Lanes

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

0 10,000 20,000 30,000 40,000 50,000 60,000

ALF Wheel Passes

HM

A L

ayer

Rut

ting,

in.

L9S1(SBS 64-40 6")

L9S2(SBS 64-40 6")

L6S1(Terpolymer 4")

L8S1(Control 6")

L10S1(Air Blown 6")

L11S1(SBS-lg 6")

L3S1(Air Blown 4")

L2S1(Control 4")

L1S1(CR AZ 4")

L4S1(SBS-lg 4")

L12S1(Terpolymer 6")

L7S1(Fibers 4")

L5S1(TBCR 4")

Fatigue Test DataFatigue Test Data

(19 (19 ooCC and 74 and 74 kNkN))

Lane 1

CR-AZ

300,000

Lane 2

Control

100,000

Lane 3

Air Blown

100,000

Lane 6

TP

200,000

Lane 4

SBS LG

300,000

Lane 5

CR-TB

100,000

Percentage of Area Cracked vs. ALF Wheel Load Passes Percentage of Area Cracked vs. ALF Wheel Load Passes

0.0

20.0

40.0

60.0

80.0

100.0

120.0

0 50000 100000 150000 200000 250000 300000 350000

Number of ALF Passes

Perc

enta

ge o

f Are

a C

rack

ed, %

L2S3 (Control)L3S3 (Air Blown)L5S3 (CR-TB)L6S3 (Terpolymer)L4S3 (SBS LG)L1S2 (CR-AZ)

0

20

40

60

80

100

120

0 100000 200000 300000 400000


Cum

ulat

ive

Cra

ck L

engt

h (m

) L3S3 (Air Blown)L2S3 (Control)L5S3 (CR-TB)L6S3 (Terpolymer)L4S3 (SBS LG)L7S3 (Fibers)L1S2 (CR-AZ)

Fatigue Cracking Length vs. ALF Wheel Load Passes Fatigue Cracking Length vs. ALF Wheel Load Passes

Rut Depth within HMA vs. ALF Wheel Load Passes(Testing Conditions: 19C & 16,600 lbs)

0

2

4

6

8

10

12

0 50,000 100,000 150,000 200,000 250,000 300,000 350,000

ALF Passes

Rut

Dep

th, m

m

L3S3 HMAL5S3 HMAL6S3 HMAL2S3 HMAL4S3 HMAL1S2 HMA

Strain Response DataStrain Response Data

(Initial and During Fatigue Test)(Initial and During Fatigue Test)

5 Gages Installed in 5 Gages Installed in Site 3 in Each LaneSite 3 in Each Lane

CTL CTL HH--Bar Strain GageBar Strain Gage

0

200

400

600

800

1000

1200

1400

1600

Lane

1 / C

R-AZ

Lane

2 / P

G 70-22

Lane

3 / A

ir-Blow

nLa

ne 4

/ SBS-LG

Lane

5 / C

R-TB

Lane

6 / T

erpoly

merLa

ne 7

/ Fibe

r

Lane

8 / P

G 70-22

Lane

9 / S

BS 64-40

Lane

10 / A

ir-Blow

n

Lane

11 / S

BS-LG

Lane

12 / T

erpoly

mer

Lane Number / Binder

Pea

k st

rain

, mic

rost

rain 19C/53kN 19C/62kN 28C/53kN 28C/62kN

Longitudinal Strains Directly Under LoadLongitudinal Strains Directly Under Load

ALF vs. LabALF vs. Lab

ALF vs. LabALF vs. Lab

•• Permanent Deformation Permanent Deformation –– RUTTINGRUTTING–– Binder (Covered)Binder (Covered)–– Mixture, SPTMixture, SPT

•• Fatigue CrackingFatigue Cracking–– Binder & MixtureBinder & Mixture

•• Other Mixture Challenges & DirectionsOther Mixture Challenges & Directions–– SPTSPT–– GyratoryGyratory–– ImagingImaging

Laboratory Mixture Laboratory Mixture CharacterizationCharacterization

SST FSCH and RSCH TestsSST FSCH and RSCH TestsFrench Permanent Rut TestFrench Permanent Rut TestHamburg WTD TestHamburg WTD TestIDT Resilient Modulus (IDT Resilient Modulus (MMrr) Test) TestSPT Dynamic Modulus (ESPT Dynamic Modulus (E**) and ) and Flow Number (FN) TestsFlow Number (FN) Tests

SST DeviceSST Device

FSCH GFSCH G** vs. 100vs. 100--mm Pavement Rut mm Pavement Rut DepthDepth

RD = - 0.001 G*FSCH + 51.0R2 = 0.84

0.0

5.0

10.0

15.0

20.0

30000 35000 40000 45000 50000

FSCH G* at 74°C (MPa)

Pave

men

t Rut

Dep

th a

t 64°

C

(mm

)

FSCH GFSCH G** vs. 150vs. 150--mm Pavement Rut mm Pavement Rut DepthDepth

RD = - 0.001 G*FSCH + 41.1R2 = 0.30

0.0

5.0

10.0

15.0

20.0

30000 35000 40000 45000 50000

FSCH G* at 74°C (MPa)

Pave

men

t Rut

Dep

th a

t 64°

C

(mm

)

RSCH Cycles to Failure vs. 100RSCH Cycles to Failure vs. 100--mm mm Pavement Rut DepthPavement Rut Depth

RD = - 0.003 NRSCH Failure + 15.8R2 = 0.99

0.0

5.0

10.0

15.0

20.0

0 1000 2000 3000 4000 5000

RSCH Cycles to Failure at 74°C

Pave

men

t Rut

Dep

th a

t 64°

C

(mm

)

Outlier = Terpolymer

RSCH Cycles to Failure vs. 150RSCH Cycles to Failure vs. 150--mm mm Pavement Rut DepthPavement Rut Depth

RD = - 0.004 NRSCH Failure + 19.0R2 = 0.77

0.0

5.0

10.0

15.0

20.0

0 1000 2000 3000 4000 5000


Pave

men

t Rut

Dep

th a

t 64°

C

(mm

)

French PRT DeviceFrench PRT Device

French Rut Depth vs. 100French Rut Depth vs. 100--mm mm Pavement Rut DepthPavement Rut Depth

RD = 0.525 RDFrench + 7.4R2 = 0.64

0.0

5.0

10.0

15.0

20.0

0.0 5.0 10.0 15.0 20.0 25.0

French Rut Depth at 74°C (mm)

Pave

men

t Rut

Dep

th a

t 64°

C

(mm

)

French Rut Depth vs. 150French Rut Depth vs. 150--mm mm Pavement Rut DepthPavement Rut Depth

RD = 0.012 RDFrench + 14.9R2 = 0.001

0.0

5.0

10.0

15.0

20.0

0.0 5.0 10.0 15.0 20.0 25.0

French Rut Depth at 74°C (mm)

Pave

men

t Rut

Dep

th a

t 64°

C

(mm

)

Hamburg Wheel Tracking Device Hamburg Wheel Tracking Device (WTD)(WTD)

685 N80mm

• 10,000 and 20,000 passes

• 10-mm rut depth

Hamburg Rut Depth vs. 100Hamburg Rut Depth vs. 100--mm mm Pavement Rut DepthPavement Rut Depth

RD = 0.0002 RDHamburg + 9.5R2 = 0.22

0.0

5.0

10.0

15.0

20.0

0 5000 10000 15000 20000 25000Hamburg Rut Depth at 64°C (mm)

Pave

men

t Rut

Dep

th a

t 64°

C

(mm

)


Hamburg Rut Depth vs. 150Hamburg Rut Depth vs. 150--mm mm Pavement Rut DepthPavement Rut Depth

RD = - 0.0001 RDHamburg + 16.3R2 = 0.044

0.0

5.0

10.0

15.0

20.0

0 5000 10000 15000 20000 25000

Hamburg Rut Depth at 64°C (mm)

Pav

emen

t R

ut

Dep

th a

t 64

°C

(mm

)

IDT TestingIDT Testing

IDT Total Resilient Modulus vs. 100IDT Total Resilient Modulus vs. 100--mm Pavement Rut Depthmm Pavement Rut Depth

RD = - 0.006 MrTotal + 17.9R2 = 0.91

0.0

5.0

10.0

15.0

20.0

0 500 1000 1500 2000

IDT Total Resilient Modulus at 40°C (MPa)

Pave

men

t Rut

Dep

th a

t 64°

C

(mm

)

IDT Total Resilient Modulus vs. 150IDT Total Resilient Modulus vs. 150--mm Pavement Rut Depthmm Pavement Rut Depth

RD = 0.0002 MrTotal + 14.9R2 = 0.003

0.0

5.0

10.0

15.0

20.0

0 500 1000 1500 2000

IDT Total Resilient Modulus at 40°C (MPa)

Pave

men

t Rut

Dep

th a

t 64°

C

(mm

)

Laboratory Mixture Laboratory Mixture Characterization, RCharacterization, R22

TESTTEST 100mm100mm 150mm150mmSST FSCH SST FSCH 0.840.84 0.300.30SST RSCHSST RSCH 0.990.99 0.770.77French PRTFrench PRT 0.640.64 0.0010.001Hamburg WTD Hamburg WTD 0.220.22 0.040.04IDT IDT MMrr 0.91 (3 pts)0.91 (3 pts) 0.0030.003SPT |ESPT |E**|| on going testing…on going testing…SPT FNSPT FN

New SPTNew SPT

SPT |ESPT |E**| Test| Test

SPT |ESPT |E**| tests were | tests were conducted on …conducted on …•• TruckTruck•• LabLab•• CoresCores

Unconfined |EUnconfined |E**| tests were conducted at | tests were conducted at four temperatures 19, 31, 46, and 58°Cfour temperatures 19, 31, 46, and 58°C

Variability of SPT EVariability of SPT E** and FNand FN

|E*|, CV = 1 to 26|E*|, CV = 1 to 26CV < 15 in most casesCV < 15 in most cases

FN, CV = 1 to 50, howeverFN, CV = 1 to 50, howeverCV ~ 6 to 21 CV ~ 6 to 21 with cycles to 2% strainwith cycles to 2% strain

SamplingSampling

E* Master CurvesE* Master Curves--TruckTruck

1

10

100

1000

10000

100000

1E-05 1E-04 0.001 0.01 0.1 1 10 100 1000 10000Reduced Frequency (Hz)

E* (M

Pa)

PG 70-22Air-BlownCR-TBTerpolymerSBS LGSBS 64-40

E* Master CurvesE* Master Curves--LabLab

1

10

100

1000

10000

100000


E* (M

Pa)

PG 70-22Air-BlownCR-TBSBS LGTerpolymerSBS 64-40

E* Master CurvesE* Master Curves--CoresCores

1

10

100

1000

10000

100000


E* (M

Pa)

Lane 10/Air-Blown

Lane 8/PG 70-22

Lane 11/SBS LG

Lane 12/Terpolymer

Lane 9/SBS 64-40

Control (PG 70Control (PG 70--22)22)

1

10

100

1000

10000

100000

0.00001 0.001 0.1 10 1000Reduced Frequency (Hz)

E* (M

Pa)

Truck

LabCores

TerpolymerTerpolymer

1

10

100

1000

10000

100000


E* (M

Pa)

Truck

Lab

Cores

SBS Linear GraftedSBS Linear Grafted

1

10

100

1000

10000

100000


E* (M

Pa)

Truck

Lab

Cores

Hirsch Model PredictionsHirsch Model PredictionsControl (PG 70Control (PG 70--22)22)--TruckTruck

1

10

100

1000

10000

100000


E* (M

Pa)

Hirsch Model-PredictedMeasured

Area of Potential Work

Hirsch Model PredictionsHirsch Model PredictionsTerpolymerTerpolymer--Truck Truck

1

10

100

1000

10000

100000

0.00001 0.001 0.1 10 1000

Reduced Frequency (Hz)

E* (M

Pa)



Hirsch Model PredictionsHirsch Model PredictionsSBS LGSBS LG--TruckTruck

1

10

100

1000

10000

100000

0.00001 0.0001 0.001 0.01 0.1 1 10 100 1000

Reduced Frequency (Hz)

E*

(MP

a)



Hirsch Model vs. Witczak Hirsch Model vs. Witczak ModelModel

Witczak model was not used for Witczak model was not used for the mixture dynamic modulus the mixture dynamic modulus predictions for two reasons:predictions for two reasons:•• It provides similar predictions to It provides similar predictions to

those of the Hirsch model.those of the Hirsch model.•• The mixture volumetric inputs The mixture volumetric inputs

required for the Hirsch model were required for the Hirsch model were available.available.

EE**/sin /sin δ δ vs. 150vs. 150--mm Pavement Rut mm Pavement Rut DepthDepth

RD = 3E+07 (E*sin δ)-2.987

R2 = 0.91

RD = - 0.341 E*sin δ + 58.6R2 = 0.86

0.0

5.0

10.0

15.0

20.0

100 110 120 130 140 150

E*/sin δ at 0.1 Hz (MPa)

Pave

men

t Rut

Dep

th (m

m)

Outlier = Air-Blown

Linear

Power

Flow Number vs. 150Flow Number vs. 150--mm Pavement Rut mm Pavement Rut DepthDepth

RD = - 0.001 FN + 18.5R2 = 0.74

0.0

5.0

10.0

15.0

20.0

0 1000 2000 3000 4000 5000Flow Number at 64°C

Pave

men

t Rut

Dep

th a

t 64°

C

(mm

)


FN Cycles to Failure vs. 150FN Cycles to Failure vs. 150--mm mm Pavement Rut DepthPavement Rut Depth

RD = - 0.027 N2% Strain + 19.5R2 = 0.81

0.0

5.0

10.0

15.0

20.0

0 100 200 300 400 500FN Cycles to 2% Strain

Pave

men

t Rut

Dep

th a

t 64°

C

(mm

)


SPT ESPT E** RankingRanking

Highest Truck Lab Cores

PG 70-22 PG 70-22 Air-Blown

Air-Blown Air-Blown PG 70-22

CR-TB CR-TB

SBS LG SBS LG SBS LG

Terpolymer Terpolymer Terpolymer

SBS 64-40 SBS 64-40 SBS 64-40Lowest

“Understanding the “Understanding the Performance of Modifiers in Performance of Modifiers in

Asphalt Mixtures” Asphalt Mixtures” ––6767--80 Binder Study80 Binder Study

Revised T.T.S. + Revised T.T.S. + Statistical AnalysisStatistical Analysis

Materials & Construction TeamMaterials & Construction Team


6767--80 Binder Study80 Binder StudyOutlineOutline

•• 6767--80 Binders80 Binders•• Mixture CharacterizationMixture Characterization•• Research ApproachResearch Approach•• Proposed Binder ParametersProposed Binder Parameters•• ResultsResults•• ObservationsObservations

2001 ALF Pavement Facility2001 ALF Pavement FacilityTarget Grade, AB cTarget Grade, AB c--PG 74PG 74--2828

Binder IDBinder ID cc--PG HTPG HT cc--PG LTPG LT UTIUTI

1: AZ CR1: AZ CR2/8: Control2/8: Control3/10: Air3/10: Air--blownblown4/11: SBS4/11: SBS--lglg5: TBCR5: TBCR6/12: Terpolymer6/12: Terpolymer9: SBS 649: SBS 64--4040

n/an/a727274747474797974747171

n/an/a--2323--2828--2828--2828--3131--3838

n/an/a9595102102102102103103105105109109

UTI – Useful Temperature Index

In situ ALF BindersIn situ ALF Binders

-40

-34

-28

-2258 64 70 76 82

Continous High Temperature Grade, (c-HT) °C

c-LT

, °C

ControlAirblownSBS-lgTBCRTerpolySBS

ETG Concern

6767--80 Binders80 Binderscc--PG based on G*/sin PG based on G*/sin δδ Original/RTFOOriginal/RTFO

Binder IDBinder ID CodeCode cc--PG HTPG HT cc--PG LTPG LT

1: 1: EnviroEnviro. Friendly. Friendly2: EF + SBS2: EF + SBS3: Terpolymer3: Terpolymer4: Terpolymer4: Terpolymer5: Terpolymer5: Terpolymer6: Terpolymer6: Terpolymer

B6308B6308B6309B6309B6310B6310B6311B6311B6312B6312B6316B6316

777780805959686872728282

--2525--2424--3030--2828--3131--2424

6767--80 Binders80 Binderscc--PG based on G*/sin PG based on G*/sin δδ Original/RTFOOriginal/RTFO

Binder IDBinder ID CodeCode cc--PG HTPG HT cc--PG LTPG LT

7: TBCR7: TBCR8: TBCR8: TBCR9: TBCR9: TBCR

10: SBS LG10: SBS LG11: SBS LG11: SBS LG12: SBS LG12: SBS LG

B6313B6313B6314B6314B6315B6315B6324B6324B6325B6325B6326B6326

707076768282686877778484

--2525--2525--2323--2626--2323--2222

6767--80 Binders80 Binders

-40

-34

-28

-2258 64 70 76 82 88

Continous High Temperature Grade, (c-HT) °C

c-LT

, °C

EFEF + SBSTerpolyTBCRSBS lg

58 64 70 76 82 88

Mixture Test at HT cMixture Test at HT c--PGPG

•• Superpave Shear Tester (SST)Superpave Shear Tester (SST)–– Repeated Shear at Constant Height (RSCH)Repeated Shear at Constant Height (RSCH)

Cycles to 2% Strain FailureCycles to 2% Strain Failure•• Strain at 5,000 cyclesStrain at 5,000 cycles•• Strain at 1,000 cyclesStrain at 1,000 cycles

Mixture Test at HT cMixture Test at HT c--PGPG

•• Cycles to 2% Strain FailureCycles to 2% Strain Failure•• Best connection to Full Scale Rutting (ALF)Best connection to Full Scale Rutting (ALF)

RD = - 0.004 NRSCH Failure + 19.0

0.0

5.0

10.0

15.0

20.0

0 1000 2000 3000 4000 5000


150m

m Pa

veme

nt Ru

t Dep

th at

64°C

(mm)

RD = - 0.003 NRSCH Failure + 15.8

0.0

5.0

10.0

15.0

20.0

0 1000 2000 3000 4000 5000


100m

m P

avem

ent R

ut D

epth

at

64°C

(mm

)


R2 = 0.77

R2 = 0.99

150mm

100mm

Summary of 67Summary of 67--80 Mixture Testing80 Mixture TestingCV for Trimmed Mean CV for Trimmed Mean (5(5--2=3)2=3)

•• 6% < COV < 45%6% < COV < 45%•• Most ~ 15%Most ~ 15%

Working Data Set after Trimmed Working Data Set after Trimmed Mean AnalysisMean Analysis

•• Typical ExampleTypical Example

0

250

500

750

1000

1250

1500

68 70 72 74 76 78 80 82 84

SST RSCH Test Temperature, °C

Cyc

les

to 2

% S

trai

n

Trimmed Mean Variability

Much care was taken in this experiment, however, results do not always follow expected decreasing trend

– THIS IS A FACT OF LIFE WITH HT SST.

RR22 Approach…Approach…Understanding R2 behavior as linear slope approaches zero for various qualities of data.

0

0.2

0.4

0.6

0.8

1

0.0001 0.001 0.01 0.1 1 10 100 1000

Data Quality = Standard Deviation about Underlying Linear Function

R2

Slope 100

Slope 10

Slope 1

Slope 0.1

RR22 ApproachApproachUnderstanding R2 behavior as linear slope approaches zero for various qualities of data.

0

0.2

0.4

0.6

0.8

1

0.0001 0.001 0.01 0.1 1 10 100 1000

Data Quality = Standard Deviation about Underlying Linear Function

R2

Slope 100

Slope 10

Slope 1

Slope 0.1

Slope 0.000005

Conclusion – R2 is not the most appropriate method. Essentially R2=1 for a perfect horizontal Model, but HYPERSENSITIVE. Smallest deviation from perfect horizontal causes poor R2 with moderate variability.

Pivotal Question…Pivotal Question…

•• Can we perform SST tests at cooler temperature Can we perform SST tests at cooler temperature where variability is smaller ?where variability is smaller ?

•• Then……relate test data to warmer conditions Then……relate test data to warmer conditions where ETG suggests mixture tests be where ETG suggests mixture tests be performed.performed.

•• WHAT TOOLS ARE AVAILABLE TO DO WHAT TOOLS ARE AVAILABLE TO DO SOMETHING LIKE THIS WITH EXISTING DATA ?SOMETHING LIKE THIS WITH EXISTING DATA ?

Pivotal QuestionPivotal Question(NCHRP 9(NCHRP 9--19)19)

•• Utilization of Utilization of TIME TEMPERATURE TIME TEMPERATURE SUPERPOSTIONSUPERPOSTION–– Creep & Permanent Deformation at Multiple Creep & Permanent Deformation at Multiple

Temperatures…Neat 64Temperatures…Neat 64--22 Dense Graded22 Dense Graded–– It is Feasible to “Shift” Permanent Strains like |G*|It is Feasible to “Shift” Permanent Strains like |G*|

-3

-2.5

-2

-1.5

-1

-0.5

0

0 500 1000 1500 2000Reduced Time, sec

Stra

in, %

Shifted 45oC Avg. 3 ReplicatesUnshifted 35oC Avg. 3 Replicates

-3.5

-3

-2.5

-2

-1.5

-1

-0.5

0

0 1000 2000 3000 4000Reduced Time, sec

Stra

in, %

Shifted 35oC Avg. 3 ReplicatesUnshifted 25oC Avg. 3 Replicates

Current Research ApproachCurrent Research Approach•• Calibrate a SST RSCH Model with integrated Time Calibrate a SST RSCH Model with integrated Time

Temperature SuperpositionTemperature Superposition•• Determine Theoretical SST Test Result at Determine Theoretical SST Test Result at

Temperatures Determined by Candidate Binder Temperatures Determined by Candidate Binder Parameters Parameters

•• Repeat 3 times calibrating on Test DataRepeat 3 times calibrating on Test Data1.1. HIGHERHIGHER2.2. INTERMEDIATEINTERMEDIATE3.3. LOWERLOWER

Calibrate a SST RSCH Model with integrated Calibrate a SST RSCH Model with integrated Time Temperature SuperpositionTime Temperature Superposition

0

500

1000

1500

2000

2500

3000

3500

68 70 72 74 76 78 80 82 84

SST RSCH Test Temperature, oC

# S

ST

RS

CH

Cycle

s to

2%

Pe

rma

ne

nt S

tra

in

High Calib

Measured

( ) ( ) ( ) 213

223

212

23311

23322

22211 666 τττσσσσσσσ +++−+−+−=eq

212

211 3τσσ +=eq

( )( )qvp

peq

R

vp

B

Adtd

12

12

γ

σγ=

From Binder |G*|Trimmed Mean Variability

)(TattR =

Each Binder Parameter for Each Binder Has a Distinct Temperature


0

500

1000

1500

2000

2500

3000

3500

68 70 72 74 76 78 80 82 84


# S

ST

RS

CH

Cycle

s to

2%

Pe

rma

ne

nt S

tra

in

High Calib

Int. Calib

Measured

( ) ( ) ( ) 213

223

212

23311

23322

22211 666 τττσσσσσσσ +++−+−+−=eq

212

211 3τσσ +=eq

( )( )qvp

peq

R

vp

B

Adtd

12

12

γ

σγ=


)(TattR =



0

500

1000

1500

2000

2500

3000

3500

68 70 72 74 76 78 80 82 84


# S

ST

RS

CH

Cycle

s to

2%

Pe

rma

ne

nt S

tra

in

High Calib

Int. Calib

Low Calib

Measured

( ) ( ) ( ) 213

223

212

23311

23322

22211 666 τττσσσσσσσ +++−+−+−=eq

212

211 3τσσ +=eq

( )( )qvp

peq

R

vp

B

Adtd

12

12

γ

σγ=


)(TattR =


Current Research ApproachCurrent Research ApproachDetermine Proportion of Test Results that Lie

outside Effective Lumped Variability

# C

ycle

s to

2%

Str

ain

Temperature From Parameter

High Spec. Temperature, THigh Spec. Temperature, THSHS

•• |G*|/sin |G*|/sin δ = 2200 Paδ = 2200 Pa at 10 rads/sat 10 rads/s (Superpave)(Superpave)

•• |G*|/(1|G*|/(1--(1/tan(1/tanδδ sinsinδ)) = 50 Paδ)) = 50 Pa at 0.25 rads/sat 0.25 rads/sCriterion 1 Criterion 1 (FHWA)(FHWA)

•• TTE E /(1/(1--(1/tan(1/tanδδ sinsinδ)) where Tδ)) where TEE is when |G*|= 50 is when |G*|= 50 PaPa at 0.25 rads/sat 0.25 rads/sCriterion 2 Criterion 2 (FHWA)(FHWA)

High Spec. Temperature, THigh Spec. Temperature, THSHS

•• η’ = 220 Paη’ = 220 Pa--ss, LSV , LSV at 0.01 rads/sat 0.01 rads/s (Binder ETG)(Binder ETG)

•• ηη00 = 250 Pa= 250 Pa--ss, ZSV , ZSV at 0 rads/sat 0 rads/s (Binder ETG)(Binder ETG)

•• MVR MVR = 50 cc/10min= 50 cc/10min at 1.225 kg loadat 1.225 kg load (FHWA)(FHWA)

High Temperature ParametersHigh Temperature Parameters

•• % γ% γaccacc Repeated Creep Repeated Creep @@300 Pa 300 Pa (NCHRP 9(NCHRP 9--10)10)

•• % γ% γaccacc Repeated Creep Repeated Creep @@25 Pa 25 Pa (NCHRP 9(NCHRP 9--10)10)

Results Results -- ExampleExample

SST Test Results Determined Using Time-Temp Superposition at Different Individual Binder Parameter Temperatures

0

0.001

0.002

0.003

0.004

0.005

0.006

0 500 1000 1500 2000 2500 3000

SST RSCH Cycles to 2% Strain

No

ma

l D

istr

ibu

tio

n F

req

ue

nc

y

B6313 CRTB PG70-25B6314 CRTB PG76-25B6315 CRTB PG82-23B6324 SBS-LG PG68-26B6325 SBS-LG PG77-23B6326 SBS-LG PG84-22B6310 TP PG59-30B6312 TP PG72-31B6316 TP PG82-24Effective Combined

|G*|/sin δ

Intermediate SST Calibration

Results Results ––Lower SST CalibrationLower SST Calibration

|G*| sind

|G*| (1-(1/tandsind))

TE (1-(1/tandsind)) ZSV LSV MVR

B6313 CRTB PG70-25 27.6% 5.3% 1.0% 4.8% 4.4% 24.4%B6314 CRTB PG76-25 30.9% 28.7% 28.6% 29.9% 28.6% 28.6%B6315 CRTB PG82-23 1.0% 0.7% 0.5% 0.6% 1.0% 1.7%B6324 SBS-LG PG68-26 0.0% 0.0% 0.0% 0.0% 0.0% 0.0%B6325 SBS-LG PG77-23 0.0% 0.0% 0.0% 0.0% 0.0% 0.0%B6326 SBS-LG PG84-22 0.1% 0.1% 0.0% 0.1% 0.1% 0.1%B6310 TP PG59-30 5.5% 3.1% 5.3% 0.0% 10.4% 19.4%B6312 TP PG72-31 2.7% 3.2% 3.3% 3.1% 3.4% 3.3%B6316 TP PG82-24 59.6% 59.3% 59.4% 59.3% 59.3% 59.4%

6 of 9 7 of 9 7 of 9 7 of 9 6.5 of 9 5 of 9

Calibration at Lower SST Temperature

Binder\Parameter

Results Results ––Intermediate SST Temp CalibrationIntermediate SST Temp Calibration

|G*| sind




1 of 9 4 of 9 4.5 of 2.5 of 3 of 9 2 of 9

Calibration at Higher SST Temperature

Binder\Parameter

Results Results ––Higher SST Temp CalibrationHigher SST Temp Calibration

|G*| sind




1 of 9 4 of 9 4.5 2.5 3 of 9 2 of 9

Calibration at Higher SST TemperatureBinder\Parameter

ObservationsObservations•• Utilization of the Lower and Intermediate T.T.S. Utilization of the Lower and Intermediate T.T.S.

Calibrations is desired…Calibrations is desired…–– Higher Temp Calibration has strongest potential for Higher Temp Calibration has strongest potential for

variabilityvariability–– Lower and Intermediate compare with each otherLower and Intermediate compare with each other

•• Lower Calibration (7 of 9)Lower Calibration (7 of 9)11--(1/(1/tantanδ δ sinsinδδ) methods and ZSV capture more ) methods and ZSV capture more behaviorbehavior

•• Intermediate Calibration (4~ or 9)Intermediate Calibration (4~ or 9)11--(1/(1/tantanδ δ sinsinδδ) methods and LSV capture more ) methods and LSV capture more behaviorbehavior

ObservationsObservations

•• Cooler tests with less variability are Cooler tests with less variability are needed to further analyze the “tied” needed to further analyze the “tied” parametersparameters

Next Steps… Next Steps… High Temperature ParametersHigh Temperature Parameters

•• NonNon--recovered Compliance after 50 cyclesrecovered Compliance after 50 cyclesRepeated Creep Repeated Creep @ @ 50Pa, 100Pa, 500Pa, 1000Pa, 50Pa, 100Pa, 500Pa, 1000Pa, 1600Pa, 3200Pa 1600Pa, 3200Pa (Binder ETG)(Binder ETG)

•• NonNon--recovered Compliance Multirecovered Compliance Multi--stress after 10 stress after 10 cyclescycles Repeated Creep Repeated Creep @ @ 25Pa, 50Pa, 100Pa, 25Pa, 50Pa, 100Pa, 200Pa, 400Pa, 800Pa, 1600Pa, 3200Pa 200Pa, 400Pa, 800Pa, 1600Pa, 3200Pa

(Binder ETG)(Binder ETG)

Next Steps.Next Steps.•• Revise with FRevise with F--Distribution or Distribution or

ChiChi22--Distribution where 0<x<Distribution where 0<x<•• ActualActual cooler (45cooler (45ooC) SST tests C) SST tests

shifted up to warmer tests shifted up to warmer tests ––i.e. adjust frequency of SST i.e. adjust frequency of SST pulsepulse

OROR•• Revised Flow Number test, of Revised Flow Number test, of

which we have capability to which we have capability to modify test softwaremodify test software

8

ACTION ITEMSACTION ITEMS

•• What additional binder should be What additional binder should be considered? considered? –– Is 7 or 9 good enough?Is 7 or 9 good enough?

•• Should additional aggregate structures be Should additional aggregate structures be considered?considered?

Binder ParametersBinder Parameters

1.1. SuperpaveSuperpave|G*| sin |G*| sin δδ = G” (loss modulus)= G” (loss modulus)

2.2. FHWAFHWA|G*|G*ss|| sinsinδδss = = GG""s s (Strain Sweep)(Strain Sweep)

3.3. EEssential ssential WWork of ork of FFracture (EWF) racture (EWF) Simon Simon Hesp Hesp & Jack Youtcheff

TTISIS is the temperature where |G*|is the temperature where |G*|sinsinδδ = 5 M Pa at = 5 M Pa at ωω = 10 rad/s low strains (0.1= 10 rad/s low strains (0.1--0.4%), PAV0.4%), PAV

& Jack Youtcheff

|G*|sin|G*|sinδδ −− FailureFailure

Bahia, H. U., Hanson, D. I., Zeng, M., Zhai, H., Khatri, M. A. aBahia, H. U., Hanson, D. I., Zeng, M., Zhai, H., Khatri, M. A. and Anderson, M. A. (2001). nd Anderson, M. A. (2001). ““Characterization of modified asphalt binders in Superpave mix deCharacterization of modified asphalt binders in Superpave mix design.sign.”” National Cooperative National Cooperative Highway Research Program NCHRP Report 459, Highway Research Program NCHRP Report 459, Transportation Research Board Transportation Research Board -- National Research National Research Council, National Academy Press, Washington D.C.Council, National Academy Press, Washington D.C.

Gravel Fine Aggregate

R2 = 0.1878

4.0E+06

6.0E+06

8.0E+06

1.0E+07

1.2E+07

0 20000 40000 60000 80000 100000

Mixture Fatigue Life (N50)

Bin

der |

G*|

sin

δ (P

a)

|G*|G*ss|sin|sinδδss −− Strain Sweep Strain Sweep

Shenoy, Aroon (2002). Shenoy, Aroon (2002). ““Fatigue testing and evaluation of asphalt binders using the dynaFatigue testing and evaluation of asphalt binders using the dynamic shear mic shear rheometer.rheometer.”” Journal of Testing and EvaluationJournal of Testing and Evaluation, , 30(4), 30330(4), 303--312. 312.

G" from strain sweep versus Cycles to Failure

750000800000850000900000950000

0 500 1000N f

G" s

=|G

* s|s

inδ

s

B6225 @24CB6226 @29CB6227 @26CB6228 @19CB6229 @23CB6230 @20CB6231 @22CB6232 @25CB6233 @21CB6243 @14CB6251 @23CAC-5 @16CAC-20 @25CStyrelf @24CNovophalt @30CBest Line

R 2=0.82

EWFEWF −− Ductile fracture energy that is Ductile fracture energy that is dissipated during the binder fracture testdissipated during the binder fracture test

(No Criterion Yet)(No Criterion Yet)

L

80 mm

30 mm

Andriescu, A., Hesp, S. A. M. and Youtcheff, J. S. (2004). Andriescu, A., Hesp, S. A. M. and Youtcheff, J. S. (2004). ““On the Essential and Plastic Works of On the Essential and Plastic Works of Ductile Fracture in Asphalt Binders.Ductile Fracture in Asphalt Binders.”” 83rd Annual Meeting of the Transportation Research Board, Washington DC.

•• Ligament lengths (L): 5, 10, 15, 20 and 25 mmLigament lengths (L): 5, 10, 15, 20 and 25 mm

•• Sample thickness (B): 6.5 mmSample thickness (B): 6.5 mm

•• Strain rate = 100 mm/minStrain rate = 100 mm/min

•• T = 25T = 25ooCC

Summary of Binder and ALF Summary of Binder and ALF Fatigue DataFatigue Data

Parameter 1Parameter 1 Parameter 2Parameter 2 Parameter 3Parameter 3 ALF Data

Crack Length (m)

at 100K ALF

Passes

ALF Passes at

50 m Crack Length

90.690.6

115115

00

24.924.9

99

BinderBinder

|G*|sin|G*|sinδ δ value at value at

1919°°C, C, 10 rads/s, 10 rads/s,

0.4% 0.4% strain, PAV strain, PAV

TTISIS when when |G*|sin|G*|sinδδ = =

5 MPa 5 MPa (10 rads/s, (10 rads/s,

0.4% 0.4% strain, strain, PAV)PAV)

|G*|G*ss|sin|sinδδssvalue at value at

1919°°C, C, 10 rads/s, 10 rads/s,

25% strain, 25% strain, RTFOTRTFOT

TTISIS = = TTEEsinsinδδss

where Twhere TEE is is when |G*when |G*ss| |

= 1 MPa = 1 MPa (10 rads/s, (10 rads/s, 25% strain, 25% strain,

RTFOT)RTFOT)

EWF EWF (kJ/m(kJ/m22))

ControlControl 1210000012100000 26.026.0 39400003940000 28.128.1 7.937.93 6627966279

Air Air BlownBlown

68100006810000 22.622.6 23900002390000 24.824.8 7.847.84 4797347973

SBSSBS--lglg 40600004060000 18.118.1 13600001360000 19.219.2 10.810.8 270029270029

TBCRTBCR 42100004210000 17.917.9 12800001280000 19.119.1 4.414.41 154651154651

TerTer--polymerpolymer

26100002610000 14.314.3 910000910000 16.816.8 4.704.70 175171175171

Summary of Binder RankingsSummary of Binder Rankings


Crack Length (m)

at 100K ALF

Passes

DD

EE

AA

CC

BB

ALF Passes at

50 m Crack Length

BinderBinder


1919°°C, C, 10 rads/s, 10 rads/s,






1919°°C, C, 10 rads/s, 10 rads/s,





RTFOT)RTFOT)


ControlControl DD DD DD DD BB DDAirAir

BlownBlown CC CC CC CC BB EE

SBSSBS--lglg BB BB BB BB AA AATBCRTBCR BB BB BB BB CC CCTerTer--

polymerpolymer AA AA AA AA CC BB

Binder RankingsBinder RankingsConsistent with ALF Data.Consistent with ALF Data.


Crack Length (m)

at 100K ALF

Passes

DD

EE

AA

CC

BB

ALF Passes at

50 m Crack Length

BinderBinder


1919°°C, C, 10 rads/s, 10 rads/s,






1919°°C, C, 10 rads/s, 10 rads/s,





RTFOT)RTFOT)


ControlControl DD DD DD DD BB DDAirAir




Binder RankingsBinder RankingsTop , Bottom .Top , Bottom .


Crack Length (m)

at 100K ALF

Passes

DD

EE

AACC

BB

ALF Passes at

50 m Crack Length

BinderBinder


1919°°C, C, 10 rads/s, 10 rads/s,






1919°°C, C, 10 rads/s, 10 rads/s,





RTFOT)RTFOT)


ControlControl DD DD DD DD BB DDAir Air




Statistical RelationshipsStatistical RelationshipsRR22

Parameter 1Parameter 1 Parameter 2Parameter 2 Parameter 3Parameter 3

ALF Data

R-squared R2

|G*|sin|G*|sinδ δ value value at 19at 19°°C, C,

10 rads/s, 10 rads/s, 0.4% strain, 0.4% strain,

PAV PAV



0.4% strain, 0.4% strain, PAV)PAV)


1919°°C, C, 10 rads/s, 10 rads/s,


TTISIS = T= TEEsinsinδδsswhere Twhere TEEis when is when

|G*|G*ss| = 1 MPa | = 1 MPa (10 rads/s, (10 rads/s, 25% strain, 25% strain,

RTFOT)RTFOT)

EWF (kJ/mEWF (kJ/m22))

Crack Length (m) at100K LoadPasses & 19°C

0.56 0.71 0.61 0.78 0.013

ALF Passes at 50 m Crack Length & 19°C

0.47 0.50 0.50 0.59 0.058

Mixture CharacterizationMixture Characterization

Bending Beam Fatigue TestsBending Beam Fatigue TestsDifferent Analysis Methods and CriteriaDifferent Analysis Methods and CriteriaDynamic Modulus (EDynamic Modulus (E**))IDT Tensile Strength (SIDT Tensile Strength (Stt))

On going testing and analysis…On going testing and analysis…

Bending Beam Fatigue Bending Beam Fatigue DeviceDevice

Fatigue Testing Procedure…Fatigue Testing Procedure…

Bending Beam Fatigue Test:

Conducted according to AASHTO provisional test method TP8-94 (2002).

Strain-controlled mode at a high strain level of 1250 micro-strains.

Test temperature = 19°C.

Fatigue Testing ProcedureFatigue Testing Procedure

Bending Beam Fatigue Test:

A vertical sinusoidal displacement is applied at a frequency of 10 Hz with no rest periods.

Test run up to approximately 300,000 load cycles.

Bending Beam Fatigue Test Schematic Bending Beam Fatigue Test Schematic DiagramDiagram

Two concentrated and symmetrical loads.

Reaction Reaction

Load LoadSpecimenClamp

Deflection

SpecimenRepeated sinusoidal loading at 10 Hz frequency.

Specimen forced back to its original position at the end of each load pulse.

Bending Beam Fatigue Testing Bending Beam Fatigue Testing TheoryTheory

V

M

Specimen subjected to 4-point bending.

P/2 P/2

R R

a=l/3

Shear:

R = P = V

Moment:

M = Pa

a a

l

h

Freedom Conditions of Beam Fatigue TestFreedom Conditions of Beam Fatigue Test

Specimen subjected to 4-point bending.

Free rotation and horizontal translation at all loads and reaction points.

OutlineOutline

ALF and Bending Beam Fatigue TestsALF and Bending Beam Fatigue TestsDifferent Analysis Methods and CriteriaDifferent Analysis Methods and CriteriaLab Fatigue vs. ALF Fatigue and RankingLab Fatigue vs. ALF Fatigue and RankingDynamic Modulus (EDynamic Modulus (E**) vs. ALF Fatigue) vs. ALF FatigueIDT Tensile Strength (SIDT Tensile Strength (Stt) vs. ALF Fatigue) vs. ALF FatigueFuture PlansFuture Plans

Different Fatigue Failure Methods and Different Fatigue Failure Methods and CriteriaCriteria

50% reduction in stiffness adopted by the AASHTO (TP8-94 [2002]).

Ratio of dissipated energy change (Ghuzlan and Carpenter (TRR 1723 [2000]).

Stress-strain Hysteresis loop or sinusoidal waveform progressive distortion (Al-Khateeb and Shenoy (AAPT Journal [2004]).

5050--Percent Reduction in Percent Reduction in StiffnessStiffness

0

220

440

660

880

0 50000 100000 150000 200000

Number of Load Cycles, N

50-percent stiffness reduction

Ratio of Dissipated Energy Ratio of Dissipated Energy Change…Change…

Dissipated energy ratio Rw:

N

NNw w

wwR

−= +1

where:wN+1 = Dissipated energy in (N+1)th

cycle; wN = Dissipated energy in Nth cycle.

Ratio of Dissipated Energy Ratio of Dissipated Energy Change Change

Energy ratio decreases in the first part of the fatigue test, and then fluctuates around a flat plateau, then sharply increases.

The failure point is when the curve shoots up.

Hysteresis Loop CriterionHysteresis Loop Criterion(Before Fatigue Failure)(Before Fatigue Failure)

(a) Before Failure

-500

-300

-100

100

300

500

-0.002 0 0.002 0.004 0.006 0.008 0.01

Strain (m/m)

Stre

ss (k

Pa)

90,000 110,000130,000 170,000150,000

Hysteresis Loop CriterionHysteresis Loop Criterion(First Fatigue Failure)(First Fatigue Failure)

(b) First Failure

-300

-100

100

300

0.008 0.009 0.01 0.011 0.012 0.013 0.014 0.015 0.016

Strain (m/m)

Str

ess (

kP

a)

190,000 210,000 230,000

Hysteresis Loop CriterionHysteresis Loop Criterion(Complete Fatigue Failure)(Complete Fatigue Failure)

(c) Complete Failure

-300

-100

100

300

0.014 0.016 0.018

Strain (m/m)

Stre

ss (k

Pa) 250,000 270,000

OutlineOutline


ALF Load Passes vs. Crack ALF Load Passes vs. Crack LengthLength

0

20

40

60

80

100

120

0 100000 200000 300000 400000


Cum

ulat

ive

Cra

ck L

engt

h (m

)

L3S3 (Air Blown)L2S3 (Control)L5S3 (CR-TB)L6S3 (Terpolymer)L4S3 (SBS LG)L7S3 (Fibers)L1S2 (CR-AZ)

ALF Load Passes vs. % Area CrackedALF Load Passes vs. % Area Cracked

0

20

40

60

80

100

120

0 100000 200000 300000 400000


Perc

enta

ge o

f Are

a C

rack

ed, %

L2S3 (Control)L3S3 (Air Blown)L5S3 (CR-TB)L6S3 (Terpolymer)L4S3 (SBS LG)L1S2 (CR-AZ)

ALF Load Passes at 50ALF Load Passes at 50--m Crack m Crack LengthLength

050000

100000150000200000250000300000

ALF

Pas

ses

at 5

0-m

Cra

ck L

engt

h

Lane 3

/Air B

lownLan

e 2/70

-22Lan

e 5/C

R-TB

Lane 6

/Terp

olymer

Lane 4

/SBS LG

Cycles to Failure from Bending Beam Cycles to Failure from Bending Beam Fatigue TestFatigue Test

050,000

100,000150,000200,000250,000

Cyc

les

to

Failu

re

Lanes

3&10

/Air B

lownLan

e 1/A

Z-CR

Lanes

6&12

/Terpo...

Lane 9

/SBS 64-40

OutlineOutline


EE** sin sin δδ vs. ALF Fatigue…vs. ALF Fatigue…

Does EDoes E** sin sin δδ correlate well with the correlate well with the ALF fatigue cracking?ALF fatigue cracking?

If not, what other mixture If not, what other mixture parameters could capture the ALF parameters could capture the ALF fatigue?fatigue?

EE** sin sin δδ vs. ALF Passes at 50vs. ALF Passes at 50--m Crack m Crack Length…Length…

N50-m CL = 1E+19 (E*sin δ) -4.212

R2 = 0.760

100000

200000

300000

0 500 1000 1500 2000 2500 3000

E* sin δ at 10 Hz

ALF

Pas

ses

at 5

0-m

Cra

ck

Leng

th

EE** sin sin δδ vs. ALF Passes at 50vs. ALF Passes at 50--m Crack m Crack LengthLength

N50-m CL = 2E+10 (E*sin δ)-1.827

R2 = 0.850

100000

200000

300000

0 200 400 600 800 1000 1200

E* sin δ at 0.1 Hz

ALF

Pas

ses

at 5

0-m

Cra

ck

Leng

th

EE** sin sin δδ vs. Crack Length at 100,000 ALF vs. Crack Length at 100,000 ALF Passes…Passes…

CL100,000 ALF Passes = 0.150 (E*sin δ) - 256.6R2 = 0.80

0

50

100

150

0 500 1000 1500 2000 2500 3000

E* sin δ at 10 Hz

Cra

ck L

engt

h at

100

,000

ALF

Pa

sses

EE** sin sin δδ vs. Crack Length at 100,000 ALF vs. Crack Length at 100,000 ALF PassesPasses

CL100,000 ALF Passes = 0.184 (E*sin δ) - 83.5R2 = 0.88

0

50

100

150

0 200 400 600 800 1000 1200

E* sin δ at 0.1 Hz

Cra

ck L

engt

h at

100

,000

ALF

Pa

sses

EE** sin sin δδ vs. ALF Fatiguevs. ALF FatigueIt seems that EIt seems that E** sin sin δδ correlate very well correlate very well with the ALF passes at 50with the ALF passes at 50--m fatigue crack m fatigue crack length, Rlength, R22 = 0.76 and 0.85 for 10 Hz and = 0.76 and 0.85 for 10 Hz and 0.1 Hz, respectively (Power Relationship).0.1 Hz, respectively (Power Relationship).

Also EAlso E** sin sin δδ correlate very well with the correlate very well with the ALF fatigue crack length at 100,000 ALF fatigue crack length at 100,000 passes, Rpasses, R22 = 0.80 and 0.88 for 10 Hz and = 0.80 and 0.88 for 10 Hz and 0.1 Hz, respectively (Linear Relationship).0.1 Hz, respectively (Linear Relationship).

OutlineOutline


IDT Tensile Properties vs. ALF IDT Tensile Properties vs. ALF Fatigue…Fatigue…

How well the tensile properties How well the tensile properties from the IDT correlate with the from the IDT correlate with the ALF pavement fatigue cracking?ALF pavement fatigue cracking?

IDT SIDT Stt vs. ALF Passesvs. ALF Passes

ALF Passes = - 244.08 St + 414993R2 = 0.27

0

100000

200000

300000

0 200 400 600 800 1000 1200 1400IDT Tensile Strength (kPa)

ALF

Pas

ses

at 5

0-m

Cra

ck

Leng

th

IDT IDT εεtt vs. ALF Passesvs. ALF Passes

ALF Passes = - 170.63 εt + 448916R2 = 0.52

0

100000

200000

300000

0 500 1000 1500 2000 2500IDT Tensile Strain at Failure (microstrains)

ALF

Pas

ses

at 5

0-m

Cra

ck

Leng

th

IDT SIDT Stt vs. ALF Crack vs. ALF Crack LengthLength

Crack Length = 0.192 St - 164.2R2 = 0.69

0

20

40

60

80

100

0 200 400 600 800 1000 1200 1400

IDT Tensile Strength (kPa)

Cra

ck L

eng

th a

t 10

0,00

0 A

LF

Pas

ses

(m)

IDT IDT εεtt vs. ALF Crack Lengthvs. ALF Crack Length

Crack Length = 0.089 εt - 115.5R2 = 0.58

0

20

40

60

80

100

0 500 1000 1500 2000 2500

IDT Tensile Strain at Failure (microstrains)

Cra

ck L

engt

h at

100

,000

ALF

Pa

sses

(m)

IDT Tensile Properties vs. ALF IDT Tensile Properties vs. ALF Fatigue Fatigue

The IDT tensile strength seems to have The IDT tensile strength seems to have good correlation with the crack length at good correlation with the crack length at 100,000 passes, R100,000 passes, R22 = 0.69.= 0.69.

The IDT tensile strain at failure has good The IDT tensile strain at failure has good correlation with the ALF passes at 50correlation with the ALF passes at 50--m m crack length and the crack length at crack length and the crack length at 100,000 passes with R100,000 passes with R22 = 0.52, and 0.58, = 0.52, and 0.58, respectively.respectively.

OutlineOutline


Future Fatigue Testing And Future Fatigue Testing And Analysis…Analysis…

To complete the full matrix of To complete the full matrix of bending beam fatigue testing (3 bending beam fatigue testing (3 strain levels x 8 mixtures x 3 to 5 strain levels x 8 mixtures x 3 to 5 replicates = 72 to 120 tests).replicates = 72 to 120 tests).

To run uniaxial fatigue tests in To run uniaxial fatigue tests in tension at the same temperature tension at the same temperature 19°C.19°C.

Future Fatigue Testing And Future Fatigue Testing And Analysis…Analysis…

To use the aforementioned fatigue To use the aforementioned fatigue analysis methods and criteria.analysis methods and criteria.

To investigate new methods for To investigate new methods for fatigue data analysis.fatigue data analysis.

Future Fatigue Testing And Future Fatigue Testing And AnalysisAnalysis

To predict the tensile strains at the To predict the tensile strains at the bottom of the asphalt layer using the bottom of the asphalt layer using the solutions of the multisolutions of the multi--layer elastic or layer elastic or viscovisco--elastic theory.elastic theory.

To compare the predicted strains To compare the predicted strains with those measured under the ALF with those measured under the ALF pavements.pavements.

Uniaxial Fatigue Testing…Uniaxial Fatigue Testing…


Tests will be conducted at a Tests will be conducted at a temperature of 19°C.temperature of 19°C.

A vertical sinusoidal loading will be A vertical sinusoidal loading will be applied at a frequency of 10 Hz with applied at a frequency of 10 Hz with no rest periodsno rest periods. .


Tests will be conducted in the stressTests will be conducted in the stress--controlled fatigue mode.controlled fatigue mode.

Stresses in uniaxial testing are Stresses in uniaxial testing are uniform.uniform.

NewWarm-MixTechnology

Superpave Performance TesterSuperpave Performance TesterAASHTO TP 62AASHTO TP 62--0303

Performance Sample PreparationPerformance Sample Preparation

Estimation of Modulus Estimation of Modulus WitczakWitczakModelModel

))log(393532.0)log(313351.0603313.0(34

238384

42

200200

100547.0)(000017.0003958.00021.0871977.382208.0

058097.0002841.0)(001767.002923.0249937.1*log

η

ρρρρ

ρρρ

−−−++−+−

++

−

−−−+−=

fabeff

beff

a

eVVV

VE

│E*│= dynamic modulus, 105 psih = viscosity of asphalt binder, 106 psif = loading frequency, Hz

Va = air void content, percentVbeff = effective asphalt binder content, percent by volumer34 = cumulative percent retained on the 19 mm siever38 = cumulative percent retained on the 9.5 mm siever4 = cumulative percent retained on the 4.76 mm siever200 = percent passing 0.075 mm sieve

Hirsch Model (Algorithm)Hirsch Model (Algorithm)

⎥⎥⎥⎥

⎦

⎤

⎢⎢⎢⎢

⎣

⎡

+⎟⎠⎞

⎜⎝⎛ −

−+⎥

⎦

⎤⎢⎣

⎡⎟⎠

⎞⎜⎝

⎛+⎟

⎠⎞

⎜⎝⎛ −=

)(*3000,200,4100

1

1000,10

*3100

1000,200,4|*|

VFAGVMA

VMAPVMAxVFA

GVMAPE

binder

cbindercmix

Where,

58.0

58.0

)(*3650

)(*320

⎟⎟⎠

⎞⎜⎜⎝

⎛+

⎟⎟⎠

⎞⎜⎜⎝

⎛+

=

VMAVFAG

VMAVFAG

Pc

Information needed for estimation Information needed for estimation of |E*|of |E*|

•• Gradation of the hot mixGradation of the hot mix•• Volumetric properties of the hot mixVolumetric properties of the hot mix•• Asphalt Binder propertiesAsphalt Binder properties

Aggregate Shape Properties and Aggregate Shape Properties and Influence on HMA PerformanceInfluence on HMA Performance

AIMS System, Developed Eyad MasadManufacture red by Pine Instruments

Strain @ Flow

y = 0.8685x + 931.09R2 = 0.8795

0

5000

10000

15000

20000

25000

30000

35000

40000

0 5000 10000 15000 20000 25000 30000 35000 40000 45000

Measured, microstrain

Pre

dict

ed, m

icro

stra

in

From Consensus to Performance From Consensus to Performance Based Aggregate CriteriaBased Aggregate Criteria

Superpave Gyratory Superpave Gyratory Compactor CalibrationCompactor Calibration

• Determine the relationship between mix stiffness and eccentricity

• Establish an average mix eccentricity “Standard Stiffness” for calibration

• Compare the RAM and the HMS

• Evaluate Mix-less procedures to DAV

FHWA Paper StudyFHWA Paper StudyIN DOTIN DOT251912.59.54.752.361.180.60.30.075

0 1 2 3 4 5

Sieve Opening Raised to 0.45 Power

0

10

20

30

40

50

60

70

80

90

100

Perc

ent P

assi

ng

SampleMax DensityControl Points

FHWA 0.45 Power ChartColorado Mix - Sampled Aug 2001

19mm CO Production HMA

Normal Distributions

0

5

3.0 3.2 3.4 3.6 3.8 4.0 4.2 4.4 4.6 4.8 5.0

Compacted Air Void Content, %

Dis

trib

utio

n, f(

x, s

)

Pine InstrumentsHMA Lab Supply

Pine Instruments

HMA Lab Supply

24%

FHWA Paper StudyFHWA Paper StudyIN DOTIN DOT251912.59.54.752.361.180.60.30.075

0 1 2 3 4 5

Sieve Opening Raised to 0.45 Power

0

10

20

30

40

50

60

70

80

90

100

Perc

ent P

assi

ng

SampleMax DensityControl Points

FHWA 0.45 Power ChartColorado Mix - Sampled Aug 2001

3 3.5 4 4.5 5 5.5Air Void Content @ 50 Gyrations

HMA-2 Paper Mean = 3.74Std. Dev. = 0.24n=6

Pine Paper Mean = 3.97Std. Dev. = 0.25n=13

No Paper, OilMean = 4.08Std. Dev. = 0.18n=13

HMA-1 PaperMean = 4.39Std. Dev. = 0.29n=13

19mm CO Production HMA

ONGOING ONGOING RefinementRefinement

•• Understanding modifiersUnderstanding modifiers•• Understanding acidUnderstanding acid•• Improved moisture testImproved moisture test•• Construction qualityConstruction quality•• Link to pavement designLink to pavement design•• Communication! Communication!

CHALLENGES

“What kind of cup do we have?”“What kind of cup do we have?”

++++

++++

++ +++

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