ASPHALTopics | Summer 2014 | VOL 27 | NO3

More documents

Recommendations

Info

Multiple Stress Creep Recovery procedure improves testing of asphalt binders MGAC project north of Guelph on Wellington Road 7 28 OHMPA | ASPHALTOPICS
y Lisa Fattori in April <strong>2014</strong>, OHMPA published Ontario draft contract language for the new Multiple Stress Creep Recovery (MSCR) graded asphalt cement. The material specification replaces the Superpave Performance Graded (PG) asphalt binder specification and has been identified as MGAC (MSCR Graded Asphalt Cement) to avoid confusion. The MSCR procedure improves upon previous testing methods to provide information about both the performance and formulation of the asphalt binder through a single test. For heavy traffic areas that require elastomeric polymers in the binder, the test provides a more accurate assessment of how the asphalt cement will perform. “We’re always looking for improved tests for both high and low temperatures, and the existing test didn’t capture all of the characteristics of modified systems,” says John D’Angelo PhD., CEO of D’Angelo Consulting LLC in Washington D.C. “This test is an improvement because it looks at both modified and unmodified binders. The previous test used the same equipment, but just looked at low stress levels – small loading and movement – and didn’t capture how the AC would react under high traffic or stress levels. This test gives us a lot more detail; performance characteristics under high temperatures and if elastomers have been added to the mix.” While working at U.S. Department of Transportation’s Federal Highway Administration (FHWA), D’Angelo was part of the research team that developed the MSCR specification. The research project began in 1999, with finalized test results submitted to the American Association of State Highway and Transportation Officials (AASHTO) in 2008. AASHTO published the MSCR test procedure as a provisional specification, and conducted trials for another six years. Since 2009, the MSCR test has been available, with a number of jurisdictions developing their own methods of implementing the specifications. FALL <strong>2014</strong> 29
Page 1: FALL 2014 | VOL27 | NO3 th Annivers
Page 4 and 5: WE DARE TO BE DIFFERENT, SO YOU CAN
Page 6 and 7: Congratulations on 40 years of comm
Page 8 and 9: WE KNOW THE ROAD. WE’VE BEEN ON I
Page 10 and 11: THE STRAIGHT GOODS 10 OHMPA | ASPHA
Page 12 and 13: For approximately 30 years, Vacuum
Page 14 and 15: that there was no real difference i
Page 16 and 17: 16 OHMPA | ASPHALTOPICS
Page 18 and 19: For the last 15 years, consumers ha
Page 20 and 21: “When you don’t have to stop fo
Page 22 and 23: An all-Canadian connected car is un
Page 24 and 25: Ladies on a paver. Undated photo fr
Page 26 and 27: 26 OHMPA | ASPHALTOPICS HMA plant f
Page 30 and 31: The MSCR test uses the creep and re
Page 32 and 33: 32 OHMPA | ASPHALTOPICS
Page 34 and 35: Only Astec has the patented Double
Page 36 and 37: Pennsylvania State Route 462 in Lan
Page 38 and 39: The Ohio Department of Transportati
Page 40 and 41: One of OHMPA’s most significant c
Page 42 and 43: 1987 1988 1989 1990 1991-92 1986 La
Page 44 and 45: 1998 1999 2000 2001 1998 Teri McKib
Page 46 and 47: 2007 2008 2009 2010 2011 2012 2013
Page 48 and 49: Asphalt Cement Specifications in On
Page 50 and 51: currently known. It has been adopte
Page 52 and 53: Special Profile Eddie DeToro, found
Page 54 and 55: 50 stability machines. Call, write,
Page 56 and 57: Albarrie’s Door Seals & Dryer/Dru
Page 58 and 59: The effect of polymer modification
Page 60 and 61: occasions when the results for one
Page 62 and 63: ENVIRONMENT COMMITTEE A commitment
Page 64 and 65: Why OHMPA? We asked some of our mem
Page 66: THE LAST WORD by Gerry Chaput Succe

ASPHALTopics | Summer 2014 | VOL 27 | NO3

Create successful ePaper yourself

Delete template?

Save as template?