High Modulus Asphalt (HiMA) Technology Transfer (T2) May ... - CSIR

High Modulus Asphalt (HiMA) 

Technology Transfer (T 2 ) 

May 2010 Progress report 

Prepared for presentation at the 19 th meeting of 

the Roads Pavements Forum (RPF), Salt Rock, 5 

May 2010 

Erik Denneman

Presentation structure 

• Background on HiMA, 

• The sabita HiMA T 2 project, 

• Progress, 

• Preliminary results, 

• Way forward. 

Slide 2 

© CSIR 2006 www.csir.co.za

High Modulus Asphalt (HiMA) 

• Origin: France early 90s “Enrobés à Module Elevé” 

(EME) 

• Typical characteristics: 

• High binder content ≈ 6% by mass of aggregate, 

• Hard binder: Pen 10-25, 

• Low air voids content, 

• High Modulus > 14 GPa at 10°C, 25 Hz, 

• High resistance against permanent deformation, 

• Good fatigue resistance, 

• Impermeable, 

• High mixing temperature. 

Slide 3 


Slide 4 

Application examples 

Case #1: HMA vs HiMA 

70mm HiMA, 9000 MPa 70mm HMA, 3500 MPa 

150mm G1, 300 MPa 

© CSIR 2006 www.csir.co.za 

300mm C3, 1500 MPa 

Subgrade, 100 MPa

Slide 5 

Case #1: HMA vs HiMA 

Vertical plane parallel to Y-Z at X = 0 

Normal Stress ZZ 

3 

-37 

-77 

-116 

-156 

-195 

-235 

-275 

-314 

-354 

-394 

-433 

-473 

-512 

-552 

-592 

-631 

-671 

-710 

-750 

Vertical plane parallel to Y-Z at X = 0 

HiMA HMA 


Normal Stress ZZ 

3 

-37 

-77 

-116 

-156 

-196 

-235 

-275 

-315 

-354 

-394 

-434 

-473 

-513 

-553 

-592 

-632 

-671 

-711 

-751

Case #2: BTB+HMA vs HiMA 

Slide 6 

50mm HMA, 3500 MPa 

180mm BTB, 5000 MPa 

450mm C3, 1500 MPa 

Subgrade, 100 MPa 

Reduction of 130mm in thickness 


100mm HiMA, 9000 MPa 

450mm C3, 1500 MPa 

Subgrade, 100 MPa

Case #3: G1+HMA vs HiMA 

Slide 7 

50mm HMA, 3500 MPa 

150mm G1, 300 MPa 

300mm C3, 1500 MPa 

Subgrade, 100 MPa 

Reduction of 130mm in thickness 


70mm HiMA, 9000 MPa 

300mm C3, 1500 MPa 

Subgrade, 100 MPa

Slide 8 

sabita HiMA T 2 project 


Slide 9 

sabita HiMA T 2 progress 

• Phase I: Feasibility, completed July 2008 

• Phase II: Prelim guidelines mix design and structural 

design 

• Task 1: Finalisation mix designs and benchmarking, 

partially completed. Task had to be revised after 

French mix design failed to make specs. 

• Task 2: Structural design and cost comparisons, 

ongoing 

• Task 3: Experimental design for phase 3, ongoing 

• Tests feed into SANRAL revision of SAPDM project 


Dynamic modulus (MPa) 

Master curve development 

100000 

10000 

1000 

Slide 10 

100 

10 

1E-06 0.001 1 1000 1000000 


Reduced frequency (Hz) 

Model (Master curve) 

-5-deg C 

5-deg C 

20-deg C (Tref) 

40-deg C 

55-deg C

100000 

Dynamic Modulus (MPa) 

10000 

Comparison of mix moduli 

1000 

100 

10 

1 

0.00001 0.001 0.1 10 1000 100000 

Slide 11 © CSIR 2006 www.csir.co.za 

Reduced frequency (Hz) 

BTB Mix 

Coarse/SBS 

Medium/SBS 

HiMA

Permanent strain [%] 

Permanent deformation (RSST-CH) 

5.0% 

4.5% 

4.0% 

3.5% 

3.0% 

2.5% 

2.0% 

1.5% 

1.0% 

0.5% 

0.0% 

Mix 1 25°C Mix 1 40°C Mix 1 55°C 

Mix 2 25°C Mix 2 40°C Mix 2 55°C 

Mix 3 25°C Mix 3 40°C Mix 3 55°C 

HiMA 25°C HiMA 40°C HiMA 55°C 

0 5000 10000 15000 20000 25000 30000 

Load repetitions 

Slide 12 © CSIR 2006 www.csir.co.za

10000 

STRAIN (Microstrain) 

1000 

100 

10 

Fatigue results (10 °C 25 Hz) 

1000 10000 100000 1000000 10000000 100000000 

Slide 13 

Strain-fatigue relationship at test temperatures at 70% initial stiffness reduction 

All at 10 Degrees C 

Number of load cycles 


Mix 1 (BTB) 

Mix 3 

Mix 4 (HiMA)

French mix design effort 

Parameter Requirement Result SA equivalent 

test 

Workability 

(Gyratory 

compactor) 

Durability 

(Duriez test) 

Rutting 

(Wheel tracker) 

Beam dynamic 

modulus 

Fatigue 

(Prism) 

Slide 14 

Max 6% voids 

after 100 

gyrations 

Retained 

strength: >0.7 

Rut depth after 

30 000 cycles 

14 GPa 

µε for 106 fatigue life: 

>130 


5.7 % Gyratory 

0.9 Modified Lottmann 

5.2 mm RSST-CH, Wheel 

tracking 

17 GPa Beam or cylinder 

dynamic modulus 

90 µε Beam fatigue

Binder specifications 

Property Result Test method Specification 

Before RTFOT 

Penetration @ 25 , 10 -1 mm 25 ± 1 ASTM D5 (20-30) 

(15-25) 

Softening point, R&B, °C 62.8 ASTM D36 (55-63) 

Dynamic Viscosity @ 

60°C, Pas 2713.0 

Slide 15 © CSIR 2006 www.csir.co.za 

ASTM D4402 

(55-71) 

(≥550) 

After RTFOT 

Mass change, % (m/m) ±0.061 ASTM D2872 (±0.5) 

Softening point, R&B, °C 

Increase 

69.2 

6.4 

Penetration @ 25 , 10-1mm % Original 76 

(≤0.5) 

ASTM D36 (≥57) 

(≥ Orig. Min 

+2) 

ASTM D5 (≥55) 

(≥55)

Binder 

Mixing temperature 

Slide 16 

Mixing 

Temperature 

Lower Mixing 

HiMA Temperature 

binder Upper Mixing 

Temperature 

TMH1 C2 

Recommen 

ded 

viscosity 

Temperat 

ure at the 

viscosity 

190cSt 172°C 

150cSt 177°C 


Mixing 

Temperatu 

re Used 

175°C

Mix improvement 

• Develop mix that fulfils the requirements for: 

• Workability, 

• Durability, 

• Resistance against permanent deformation, 

• Rutting, 

• Dynamic modulus, 

• Fatigue. 

• Use French mix design as benchmark 

• Current challenge: Increase VMA to allow more binder 

and increased fatigue life 

Slide 17 


100 

90 

g 

80 

in 

s 70 

s 

a 

p 60 

e 

g 50 

ta 

n 

e 40 

r 

c 

e 30 

P 

20 

10 

Mix improvement 

0 

0 

Slide 18 

Control points 

Target 

Reference 

Trial C 

.075 .300 1.18 2.36 4.75 6.7 9.5 13.2 19.2 

.015 .600 

Sieve © size CSIR 2006 (raised www.csir.co.za to power 0.45)

Structural design 

• Short term: Use French philosophy i.e. design such 

that strains in pavement remain below threshold. 

• Medium term: Develop shift functions from APT trials. 

Slide 19 


Way forward: 

• Improve mix design 

• Complete preliminary mix design and structural design 

guideline, 

• Perform APT and LTPP, 

• Finalize mix design and structural design guidelines 

Slide 20 


Thank you

High Modulus Asphalt (HiMA) Technology Transfer (T2) May ... - CSIR

Create successful ePaper yourself

Delete template?

Save as template?