ETF Emulsion/Residue Testing Program

1. ETF Emulsion/Residue Testing Program Andrew Hanz, Codrin Daranga AASHTO TSP•2 – Emulsion Task Force (ETF) Meeting Heritage Research Group – The Center Indianapolis, IN June 12-13, 2019

2. ETF Testing Program • The principal goals of the 2017 ETF Testing Program were to: • Determine appropriate procedures to be used for high and low temperature rheological properties • Determine the need for long-term aging • Evaluate procedures intended to ensure the quality of polymer modification without excluding good performers • The principal goal of the 2018 ETF Testing Program was to: • Evaluate the draft specification refined from the 2017 ETF Testing Program

3. ETF Testing Program • Thanks! • The suppliers of the asphalt emulsion samples • The testing labs • Codrin Daranga and Shelly Cowley, Paragon Technical Services • Cristian Clopotel, Marathon Petroleum • Andrew Hanz, MTE Services • Amy Morhart and Darren Anweiler, Husky • Tim Reece and Jason Wielinski, Heritage Research Group • Texas A&M University • Dr. Amy Epps-Martin, Dr. Edith Arambula, and team • North Carolina State University • Dr. Richard Kim, Dr. Cassie Hintz, and team • Mike Voth, FHWA – Central Federal Lands • Wes Cooper, Asphalt Institute Binder Lab Manager

4. ETF Testing Program • Samples • Identification Year – UPG – Sample ID 01 (Pacific) 02 (Rocky Mountain) 03 (North Central) 04 (Southeast) 05 (Northeast) 06 (Canada) 10 (Lab) 18 01 . . . n

5. ETF Testing Program • 2018 Samples

6. 2018 ETF Testing Program Tests on Residue from AASHTO R78, Procedure B Tests on Residue from AASHTO T59, Section 7 Modified Samples Only

7. Residue Recovery • AASHTO R78, Procedure B • “Recovering Residue from Emulsified Asphalt Using Low-Temperature Evaporative Techniques” • Thin film, silicone mat • Forced draft oven at 60°C for 6 hours • High and Intermediate temperature testing for performance grading • AASHTO T59, Section 7 • “Emulsified Asphalt Residue by Evaporation” • Forced draft oven at 163°C for 3 hours • Modified asphalt emulsions only • High temperature testing for polymer identification

8. Residue Recovery • Time from residue recovery to testing matters • Guidance provided to labs: • “Before recovering the asphalt emulsion, please ensure that the test procedures will be conducted on the recovered residue within 48 hours after recovery.”

9. 2018 ETF Testing Program • High Temperature Testing on Recovered Residue • Determination of G*/sin δ • Testing Details • Perform in accordance with AASHTO T315 • 25-mm parallel plate geometry • 1-mm gap • 12% shear strain • Temperature sweep starting at 55°C and proceeding in 6°C increments until failure (the point where G*/sin δ is less than 0.65 kPa) • Report • G*/sin δ at each temperature • δ at each temperature • Tc,high – the continuous high temperature grade where G*/sin δ = 0.65 kPa • δ at Tc,high – the value of phase angle at the continuous high temperature grade

10. 2018 ETF Testing Program • High Temperature Testing on Recovered Residue • Determination of MSCR Parameters • Testing Details • Perform in accordance with AASHTO T350 • 25-mm parallel plate geometry • 1-mm gap • Test temperature at 3°C higher than LTPPBind Grade Temperature (as indicated with sample) and at 3°C lower than LTPPBind Grade Temperature • Use a new test specimen for each temperature • Report • Jnr0.1 and Jnr3.2 at each temperature • R0.1 and R3.2 at each temperature

11. 2018 ETF Testing Program • Intermediate-Low Temperature Testing on Recovered Residue • Determination of G* at critical phase angle, Gc • Testing Details • Perform in accordance with Research Draft Standard, “Determining Dynamic Shear Modulus of Emulsion Residues at Critical Phase Angle Values Using the Dynamic Shear Rheometer (DSR)” with exceptions as noted in italics below • 8-mm parallel plate geometry • 2-mm gap • 1% shear strain • Frequency sweep at each temperature starting at 0.1 rad/s and proceeding to 100 rad/s using 10 loading frequencies per decade. • Three temperatures starting at 25°C, then proceeding to 15°C, and finally 5°C • Report • G* and δ at each temperature and frequency • Gc at critical phase angle (as indicated with sample) using analysis shown in Section 12 or through use of rheological software package (please indicate which approach was used).

12. EPG High Temperature

13. EPG High Temperature

14. EPG High Temperature: Effect of Recovery 18-04-03 CRS-2P 18-10-02 CRS-2L

15. EPG Polymer Identification

16. EPG Polymer Identification

17. EPG Intermediate Temperature

18. EPG Intermediate Temperature

19. EPG Intermediate Temperature

20. Alternate High Temperature: MSCR

21. MSCR Testing to Establish “S” Grade Criterion 4.5 2.2

22. MSCR Testing to Establish “S” Grade Criterion 4.5 2.2

23. Alternate High Temperature: MSCR

24. Alternate High Temperature: MSCR

25. Alternate High Temperature: MSCR

26. Alternate High Temperature: MSCR

27. Alternate Polymer Identification: MSCR

28. Alternate Polymer Identification: MSCR

29. 2018 ETF Testing Program • Some Key Takeaways from the Analysis • Consistency in residue recovery is important to minimize variability • AASHTO R78, Procedure B has higher variability – particularly for high temperature results • AASHTO T59, Section 7 mitigates some of the variability, but changes the values

30. 2018 ETF Testing Program • Some Key Takeaways from the Analysis • Phase angle limits for polymer identification generally separate modified from unmodified emulsion residues using AASHTO R78 Procedure B recovery • 84-degree maximum generally segregates unmodified from modified residue • 80-degree maximum generally segregates polymer modified (P) from latex modified (L) residues • AASHTO T59, Section 7 recovery appears to make all modified residues pass the criterion of 80 degrees maximum • Generally greater effect on latex modified residue than polymer modified residue

31. 2018 ETF Testing Program • Some Key Takeaways from the Analysis • Intermediate temperature properties appear to be strongly impacted by low temperature grade • The lower the low temperature grade, the higher the G* at δc…regardless of whether the residue is unmodified or modified • Function of the base asphalt binder? • May see changes once formulations change to meet new specification

32. 2018 ETF Testing Program • Some Key Takeaways from the Analysis • MSCR limits suggested by NCHRP 09-50 may need to be re-evaluated • A G*/sin δ value of 0.65 kPa is comparable to a Jnr-3.2 value of approximately 17.6 kPa-1 • Twice as high as the limit for low traffic from NCHRP 09-50 research • How much will change when formulations change to adapt to new specification?

33. 2018 ETF Testing Program • Some Key Takeaways from the Analysis • MSCR • Jnr,3.2 variability still high • Not helped by variability in recovery procedure • Testing at temperature of EPG-6 appears more appropriate for discrimination of results • R0.1 at temperature of EPG-6 appears appropriate for discrimination of results • Average of CRS-2 residue = 4% • Average of CRS-2L residue = 42% • Average of CRS-2P residue = 57%

34. Thanks! Questions or Comments? Mike Anderson Asphalt Institute 859.288.4984 office manderson@asphaltinstitute.org