1. Activities as Turner-Fairbank Highway Research Center Jack Youtcheff Materials & Construction Team Federal Highway Administration www.TFHRC.gov

2. What’s Go’in On Modified Binder Research Program Modified Binder Research Program –ALF ‘93, 90-07, ALF ‘01, PG 67-80 Study Phosphoric Modification of Asphalt Binders Phosphoric Modification of Asphalt Binders –AASHTO SOM, Binder ETG Evaluation of Moisture Damage Evaluation of Moisture Damage –3D Flow Models, Fundamental Chemistry Warm Mix Asphalt Warm Mix Asphalt –WHO, IARC, EPA, NAPA, NCAT, FHWA

3. Experiment Objectives Primary Primary –Refine Superpave for Modified Binders Secondary, Evaluate… Secondary, Evaluate… –M-E Pavement Design Guide –Crumb Rubber-Modified Asphalts Arizona and Terminal Blend Processes Arizona and Terminal Blend Processes –Simple Performance Test

4. Final Test Matrix… AZ CRM ---- 70-22 1 PG 70-22 Control 2 Air Blown 3 SBS 4 TX TBCR 5 T-P 6 PG 70-22 + Fibers 7 PG 70-22 8 SBS 64-40 9 Air Blown 10 SBS 11 T-P 12

5. 12 34 Rutting T high = 64°C Fatigue T int = 19°C Fatigue T int = 28°C Replicate ALF Testing

6. ALF Testing Status (Jan. 05) - Initial Strain Measurements: Complete - Rutting Tests: All 12 Lanes Complete - Fatigue Tests: Lanes 1, 2, 4, and 5 Complete - Current Fatigue Tests: Lanes 3 and 6 12345678910 11 12 Rutting Test Fatigue Test Lane Completed Fatigue Test Completed Rutting Test Shakedown Test ALF1ALF2

7. Rutting Testing Results

8. HMA Layer Rutting among 100-mm HMA Pavements

9. HMA Layer Rutting among 150-mm HMA Pavements

10. PG 79 Lime

11. French Pavement Rutting Tester French Pavement Rutting Tester Hamburg Wheel Testing Device Hamburg Wheel Testing Device Superpave Shear Tester Superpave Shear Tester – Repeated Shear at Constant Height (RSCH) – Frequency Sweep (FS) Simple Performance Tests (under way) Simple Performance Tests (under way) Comparison to Lab Mixture Tests

12. Asphalt Mixture Pavement Thickness of 100 mm Pavement Thickness of 150 mm French PRT, Rutting at 74 o C, mm Pavement Rutting at 64 o C, mm French PRT, Rutting at 74 o C, mm Pavement Rutting at 64 o C, mm CR-AZ6.98.8 Air-Blown8.013.98.215.7 PG 70-228.613.311.115.7 SBS LG13.612.211.713.5 CR-AZ over PG 70-2214.312.7 Fiber15.110.9 Terpolymer>20.018.7>20.012.1 SBS 64-40>20.018.6 Coefficient of Determination, r 2 0.470.00 0.22 French PRT vs. Pavement Rutting

13. Asphalt Mixture Pavement Thickness of 100 mm Pavement Thickness of 150 mm Hamburg WTD, Wheel Passes at 64 o C Pavement Rutting at 64 o C, mm Hamburg WTD, Wheel Passes at 64 o C Pavement Rutting at 64 o C, mm PG 70-2220,35013.35,93615.7 Air-Blown14,90013.914,09015.7 CR-TB12,5908.8 Terpolymer9,27718.76,98012.1 SBS LG8,79012.29,87013.5 Fiber7,02010.9 SBS 64-405,14018.6 Coefficient of Determination, r 2 0.000.04 Hamburg WTD vs. Pavement Rutting

14. Asphalt Mixture Pavement Thickness of 100 mm Pavement Thickness of 150 mm Cycle at Failure at 74 o C Pavement Rutting at 64 o C, mm Cycle at Failure at 74 o C Pavement Rutting at 64 o C, mm Terpolymer3,60518.71,62412.1 CR-TB2,1218.8 SBS LG1,18512.21,37313.5 PG 70-2278313.360615.7 Air-Blown54513.951515.7 Fiber34410.9 SBS 64-4055618.6 Coefficient of Determination, r 2 0.280.77 0.01 RSCH vs. Pavement Rutting

15. Preliminary Conclusions Limited Correlation between ALF and mixture lab tests, so far… Limited Correlation between ALF and mixture lab tests, so far…Best: –100 mm: French PRT vs. ALF –150 mm: RSCH vs. ALF PG 67-80 Study… PG 67-80 Study…

16. In situ ALF Binders ETG Concern

17. 67-80 Binders 58647076 8288

18. Fatigue Testing Results

19. Lane 2 (Control) After 100,000 Loads Lane 4 (SBS LG) After 300,000 Loads Lane 5 (CR-TB) After 100,000 Loads

22. Complete ALF Fatigue Loading Complete ALF Fatigue Loading Conduct Lab Beam Fatigue Tests & SPT Conduct Lab Beam Fatigue Tests & SPT Compare ALF Results to Lab Tests Compare ALF Results to Lab Tests TWG Meeting in May/June 2005 TWG Meeting in May/June 2005 Future of APT – with TWG meeting Future of APT – with TWG meeting Continued reporting to the ETG’s Continued reporting to the ETG’s Future Plan

23. PPA

24. FHWA Research Problem Statement Acid modification has been shown to be a low cost way to increase the high temperature stiffness of asphalt binders (per Superpave Binder Specification) but… Acid modification has been shown to be a low cost way to increase the high temperature stiffness of asphalt binders (per Superpave Binder Specification) but… Studies have shown both beneficial and harmful effects of acid modification. Studies have shown both beneficial and harmful effects of acid modification. H ow should it be used? H ow should it be used? H ow should it not be used? H ow should it not be used? W hat are the pitfalls to avoid? W hat are the pitfalls to avoid?

25. Findings Regarding PPA Modification 2% PPA (85%) increases the high temperature stiffness in the range of 11.4 to 18°C or 2 to 3 PG Grades 2% PPA (85%) increases the high temperature stiffness in the range of 11.4 to 18°C or 2 to 3 PG Grades The amount of the increase is binder specific The amount of the increase is binder specific Low temperature stiffness or m-value is essentially unchanged Low temperature stiffness or m-value is essentially unchanged PPA in optimal amounts (0.3-0.7%) did not contribute to moisture sensitivity or rutting PPA in optimal amounts (0.3-0.7%) did not contribute to moisture sensitivity or rutting

26. Proposed Work Plan Develop forensic method for determining type and level of phosphate additive Develop forensic method for determining type and level of phosphate additive Asses durability of acid modification Asses durability of acid modification – Effect of environment: light, water, etc. Address corrosion and handling issues Address corrosion and handling issues Optimization of acid modification Optimization of acid modification – Chemical / mechanistic considerations – Different Asphalts – Physical Properties

27. WARM MIX ASPHALT TECHNOLOGY 44 th Annual Idaho Asphalt Conference October 21, 2004 Moscow, Idaho

28. Research Needs A cooperative agreement between FHWA and NCAT is being developed to investigate the performance of three WMA products A cooperative agreement between FHWA and NCAT is being developed to investigate the performance of three WMA products –WAM-Foam®, Aspha-Min®, Sasobit® (Sasoflex®) –Funding assistance provided by FHWA and through matching funds provided by the product companies Testing & Evaluation will be conducted at NCAT Testing & Evaluation will be conducted at NCAT –Compaction at various temperatures –Strengthening of the mixes with time –Simple performance test, dynamic modulus and moisture sensitivity, etc.

29. Research Needs Compatibility with US? Compatibility with US? –Mix designs –Equipment –Climate conditions –Work practices Success in Europe = Success in US? Success in Europe = Success in US?

30. Research Needs Investigation into Investigation into –Long term performance –Cost benefits –Plant operations Definite reduction in fuel, fumes, emissions? Definite reduction in fuel, fumes, emissions? –Control of mixing process –Workability at the paving site –Quick turnover to traffic

31. Moisture

32. Epoxy Asphalt

33. That’s all…for now Thank you Thank you