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1. Highway Engineering
Dr. Eman Magdy Ibrahim Youssef
Assistant professor, Civil Engineering Department, Delta Higher Institute of Engineering and Technology
April - 2022
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2. Hot Mix Asphalt (HMA)

3. Characterization of Asphalt Binder
Traditional tests:
1 Penetration test
2 Ring and Ball Softening Point test
3 Absolute Viscosity test
4 Kinematic Viscosity test
Performance Grade (Superpave) tests:
1 Rotational Viscometer (Brookfield) test
2 Dynamic Shear Rheometer (DSR) test
3 Bending Beam Rheometer (BBR) test
4 Direct Tension (DT) test
5 Rolling Thin Film Oven (RTFO) test
6 Pressure Aging Vessel (PAV) test
7 Flash Point test

4. Classification of Asphalt Cement
• Based on penetration
• Based on viscosity
• Based on viscosity after aging
• Based on performance
(Superpave)

5. Viscosity Graded Specifications
Viscosity: is defined as the resistance of the material to flow.
Viscosity: is the ratio between the applied shear stress and the rate of shear strain.

6. Units of Viscosity
Pa.S = Pascal. Second
• cS = Centi Stoke
• cP = Centi Poise
• P = Poise
Pa.S = 1000 cP
P = 100 cP
Stoke = 100 cS
cS = cP * Gb

7. Viscosity Tests
Absolute viscosity Kinematic viscosity

8. Absolute Viscosity Test
Absolute viscosity
– U-shaped tube with
timing marks & filled
with asphalt binder
– Placed in 60C bath
– Vacuum used to pull
asphalt through tube
– Time to pass marks
– Visc. in Pa s (Poise)

9. Kinematic Viscosity Test
Kinematic viscosity
– Cross arm tube with timing marks & filled with asphalt
– Placed in 135C bath
– Once started gravity moves asphalt through tube
– Time to pass marks
– Visc. in mm2 / s (centistoke)

10. Viscosity Grade Specifications
Viscosities at 60 and 135oC
• Penetrations at 25oC
• Flash point
• Solubility
• TFO aged residue
– Viscosity at 60oC
– Ductility at 25oC

11. AC Grades (Viscosity Grades)
AC-2.5, AC-5, AC-10, AC-20, AC-30, AC-40

12. AC Grades Example

14. Mixing/Compaction Temps

15. Ai-VTSi

16. Advantages of (Original AC Visc. Grade)
• Fundamental property
• Wide range of temperatures
• Based on max. pavement surface temp.
• Wide range of instruments
• Test method precision established
• Temperature susceptibility is controlled
• Limits aging
• Information on mixing & compaction

17. Disadvantages (Original AC Visc. Grade)
• More expensive
• Longer testing time
• More technician skill needed
• Not applicable for Non-Newtonian
materials
• Wide range of properties for same grade

18. Viscosity After Aging Graded Specifications
AR Grades
AR-10, AR-20, AR-40, AR-80, AR-160

19. AR Grades Specifications
AR Grades
– AR 1000, AR 2000, AR 4000,
AR 8000, AR 16000
• Tests on RTFO aged residue
– Viscosities at 60 and 135oC
– Penetrations at 25oC
– % of Original Penetration
– Ductility
– Properties of unaged asphalt
binders
• Flash point and solubility

20. Rolling Thin Film Oven Test (RTFOT)

21. Advantages (AR Visc. Grade)
• Represents asphalt binder properties after mixing
• Fundamental properties
• Covers wide range of temperatures
• Limits aging

22. Disadvantages (AR Visc. Grade)
• Highly regional
• Requires different testing equipment
• Longer testing time
• No consistency test on original Asphalt Binder
• Not applicable for Non-Newtonian materials
• Wide range of properties for same grade

23. Comparison of the Various Traditional Specifications

24. Characterization of Asphalt Binder
Traditional tests:
1 Penetration test
2 Ring and Ball Softening Point test
3 Absolute Viscosity test
4 Kinematic Viscosity test
Performance Grade (Superpave) tests:
1 Rotational Viscometer (Brookfield) test
2 Dynamic Shear Rheometer (DSR) test
3 Bending Beam Rheometer (BBR) test
4 Direct Tension (DT) test
5 Rolling Thin Film Oven (RTFO) test
6 Pressure Aging Vessel (PAV) test
7 Flash Point test

25. ANY QUESTIONS