1 / 33

Karl Zipf DelDOT February 2014

Grading Asphalt Binders with the Multiple Stress Creep Recovery Test AASHTO TP-70 and MP-19 “The Future is Coming”. Karl Zipf DelDOT February 2014. WARNING. Brief History of the Test. DTFH61-08-H-0003 – Cooperative Agreement between the FHWA and the Asphalt Institute

cyrah
Download Presentation

Karl Zipf DelDOT February 2014

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Grading Asphalt Binders with theMultiple Stress Creep Recovery TestAASHTO TP-70 and MP-19“The Future is Coming” Karl Zipf DelDOT February 2014

  2. WARNING

  3. Brief History of the Test • DTFH61-08-H-0003 – Cooperative Agreement between the FHWA and the Asphalt Institute • John A. D’Angelo (FHWA) • Asphalt Binder ETG • Member Companies of the Asphalt Institute – Technical Advisory Committee

  4. The present test methods for asphalt binder grading do not adequately characterize rutting or polymer-modified asphalts (PMA). • The current PG System (AASHTO M-320) is blind to modification and requires PG plus tests such as Elastic Recovery to characterize PMA binders.

  5. The PG system was supposed to reduce rutting but over the past decade and a half it has not

  6. The New Asphalt Binder Test • Uses the DSR which labs already have. • Runs the sample 10 times. Load and relax.

  7. MSCR Test Data • The test gives two values which are the basis of the standards, TP-70 and MP-19. • Jnr – Nonrecoverable creep compliance for 10 cycles at a creep stress of 3.2 kPa • % Average Recovery at a creep stress of 3.2 kPa

  8. The New Asphalt Binder Test

  9. What’s in a Name • SHRP (Sharp) – Strategic Highway Research Program • ISTEA (Ice Tea) – Intermodal Surface Transportation Equality Act • TWG (Twig) – Technical Working Group • MSCR (???) – Multiple Stress Creep Recovery

  10. “MASCAR” • Sounds like NASCAR

  11. “Massacre” • Like in the Boston Massacre

  12. “Mascara” • Both asphalt and mascara are black

  13. “Muskrat” • Multiple Stress Creep Recovery Test

  14. Jnr Limits are Based on Rut Data • The Jnr (Nonrecoverable Compliance) correlated to rut depth in the ALF track, field studies and lab tests. • The Jnr will used to determine the binder grade. • Jnr works for both modified and non-modified binders.

  15. MSCR % Recovery & Modification • Many processes will stiffen and binder but not all make them elastic. • The % Recovery is used to characterize the elasticity from polymer modification. • A polymer curve was developed based on data from available PMA binders.

  16. Polymer Modification Curve • Currently in TP-70, will move to MP-19

  17. So Far So Good • Two key values for the MSCR test • These will determine the binder grade and whether it can be called a PMA binder. • Jnr • % Recovery So how do you grade a binder?

  18. Like PG System, Grade Based on LTPP Climate Temperature

  19. Looks Familiar • USDA Plant Hardiness Zone Map

  20. Northeast StatesLTPP High, Low and USDA

  21. M-320 & MSCR Nomenclature • Right now it now it looks like the PG System • The BIG change is that everything is based on the LOCALhigh temperature environment. • Our environment is 64C and our standard grade, like the PG system is PG 64-22. • Other grades, PG 70, and PG 76 will be tested at 64C as PG 64(something), based on the Jnr. • Binder name becomes state/region dependent.

  22. MSCR and Low Temperature • The low temperature tests and nomenclature will not change with MSCR. • It still uses the BBR results. • The mid temperature criteria, the 8 mm DSR test, will have 6000 kPa as a cutoff for the stiffer grades, since for DelDOT the test temp will be 25C.

  23. MP-19 Grades at 64C • Jnr = 2.0 – 4.0 = PG 64S-22 “Standard” = PG 64-22 • Jnr = 1.0 – 2.0 = PG 64H-22 “Heavy” = PG 70-22 • Jnr = 0.5 – 1.0 = PG 64V-22 “Very Heavy” = PG 76-22 • Jnr = 0.25 – 0.5 = PG 64E-22 “Extreme” = PG 76-22 • Note MP-19 uses “High” & “Heavy” interchangeably • Standard “S” = traffic < 10 million ESALs, > 70 km/h • Heavy “H” = traffic 10-30 million ESALs, 20-70 km/h • Very Heavy “V” = traffic > 30 million ESALs, < 20km/h • Extreme “E” > 30 million ESALs, < 20km/h, toll plazas

  24. Polymer Curve & DelDOT Data

  25. Where the New Grades Fall at 64C

  26. When Will DelDOT See MP-19? • The FHWA is pushing the MSCR test ASAP. • The Asphalt Institute is pushing the MSCR test. • The NEAUPG (Northeast Asphalt User-Producer Group) is reviewing a limited regional implementation for maybe 2014. • NEAUPG will be polymer curve in 2014, and non-PMA in a future year. • SEAUPG will consider it in 2015, central USA later, and west coast probably not at all. • National implementation date is unknown.

  27. DelDOT M-320 vs MP-19 Grades • PG 58-28 = PG 58S-28, Jnr 2.0 – 4.5 58C • PG 64-22 = PG 64S-22, Jnr 2.0 - 4.5 64C • PG 64-28 = PG 64S-28, Jnr 2.0 – 4.5 64C • PG 70-22 = PG 64H-22, Jnr 1.0 – 2.0 64C • No Grade = PG 64V-22, Jnr 0.5 – 1.0 64C • For 2014 ? • PG 76-22 = PG 64E-22, Jnr < 0.5 64C and meet polymer elasticity curve.

  28. DelDOT and PG 76-22 as MSCR 64V 64E

  29. NEAUPG & PMA • From Maine to Maryland there will probably be two standard grades, PG 58S & PG 64S. • NYDOT will switch over all grades around Sept 2014 to MP-19.

  30. MSCR and RAP • Like the PG System, M-320 the MSCR spec, MP-19 is based on 100% virgin binders. • RAP is stiff, Jnr 0.1 - 0.2, but not elastic so will fail the polymer curve. • RAP affects the low temperature properties, and these rules have not changed, and it is the low temperature where one sees failure.

  31. August 2014 • The MSCR Test AASHTO TP-70 will be a full standard AASHTO T-350 • The MSCR Binder Grading AASHTO MP-19 will be a full standard, AASHTO M-322.

  32. The End(Not really. There will probably be more next year.)Questions?

  33. Implementing a New Standard

More Related