1 Green Roadway Design from a Pavements Perspective Rene’ Renteria, P.E. ODOT Pavement Design Engineer April 13, 2010

3 Green Pavements Initiatives Incorporation of Recycled Asphalt Pavement (RAP) and Recycled Asphalt Shingles (RAS) Warm Mix Asphalt (WMA)

4 Recycling of Asphalt Pavement Made a practice in early 1970’s Long-term performance is proven

5 Recycling of Asphalt Pavement Significant Reduction in Greenhouse Gas Emissions Currently average ~12.5% nationwide An Increase to 25% = 10% reduction in GHG (= 2,000,000 Tons Annually!)

6 Recycling of Asphalt Pavement

7 RAP Use on ODOT Projects 2008: 225,000 tons 2009: 450,000 tons

8 RAS Background Asphalt shingles are the most common roofing material nationwide ≈11 million tons of asphalt shingle waste is generated each year:  Manufacturer waste  ≈10%  Post consumer waste (tear-off)  ≈90% Great market potential for recycling

9 NEED: Stiff pavement when it is hot to prevent rutting. AND: Soft pavement when it is cold to prevent cracking.

10 OSU Study Overview Investigate how Recycled asphalt materials affect the stiffness and softness of the blended binder  Recycled Asphalt Pavement (RAP)  Recycled Asphalt Shingles (RAS) Recommend changes to ODOT specifications and special provisions for a pilot study

11 OSU Study Evaluate properties of original and reclaimed binders Test asphalt pavements mixtures with various proportions of RAP and/or RAS Extract & Evaluate properties of the resultant blended binders Compare properties of virgin and blended binders – How much have the properties changed?

12

13 Initial Study Findings RAS blend only & no RAP = More stiff, causing cracking  Negative impact on the blended binder 10% RAP & 5% RAS = No change in binder properties 30% RAP & 5% RAS = Significant negative effect on binder properties  possible poor pavement performance

14 Course of Action Two ODOT pilot projects planned for 2010, mandated use of RAS (1 Eastside & 1 Westside of Cascades) The pilots will require 5% RAS and allow up to 20% RAP in HMAC mix Monitor pilot project for construction issues and performance issues for a minimum of two years

15 Course of Action, cont. Modify our specifications: should we look at adjusting the properties of virgin binder? Not now but perhaps in the future. Modify our testing procedures including:  Mix design protocol  Determining binder content of RAS Allow RAS in pavements (permissive specification)?

16 Warm-Mix Asphalt May Reduce Mixing Temperatures (50º to 100º F) Temp = 320º F Temp = 245º F

17

18

19 ODOT WMA For 2009 US Latimer Road US97: OR31 Hwy Jct - SCL Crescent OR22: Independence Hwy - Willamette River  WMA placed on OR 51 US197: The Dalles - Eight Mile Creek

20 ODOT 2009 WMA Projects PROJECTWARM-MIXTONS / RAPTEMP  SYSTEM (Binder)(Deg F) Latimer Rd Foamed - Terex 1,400 / 20% PG US97: OR31 Jct - SCL Crescent Foamed - Aquablack 44,000 / 20% PG 70-28ER 45 OR22: Independence Hwy - Willamette Rvr & OR51 Additive - Evotherm 5,500 / 30% PG US197: The Dalles - Eight Mile Cr Foamed - Aquablack 17,000 / 30% PG

21 Reports of Cracking US97 and US197 have transverse cracking after first winter season  Evident within HMA and WMA on US97  December 2009 had reports of extreme cold  Investigation/Testing

22 WMA Plans for 2010 Work with ODOT Mgmt. & Industry to bring WMA onto ODOT pavement projects Reviewing projects completed in 2009  Recent meeting in February with Industry to discuss what’s been learned Modifications to Specs and Process  Adjustment to WMA temperature definition  QC/QA Testing guidelines  Mix design process

Questions?