Binder-Grade Bumping and High Binder Content to Improve Performance - PowerPoint PPT Presentation

Binder-Grade Bumping and High Binder Content to Improve Performance of RAP-RAS Mixtures Erdem Coleri Shashwath Sreedhar, Sogol Haddadi, Matthew Haynes, and Sunny Lewis

Other contribut Other butor ors • TAC members: • Larry Ilg – ODOT • Justin Moderie ‐ ODOT • Norris Shippen ‐ ODOT • Anthony Boesen ‐ FHWA • Terri Zahler from McCall Oil • Mike Miller from Oldcastle Materials

O UTLINE • I NTRODUCTION AND L ITERATURE REVIEW • E XPERIMENT TYPES • O BJECTIVES AND E XPERIMENTAL PLAN • B INDER GRADE AND BINDER CONTENT • B LENDING EVALUATION • I NITIAL RESULTS • S UMMARY

INTRODUCTION AND LITERATURE REVIEW

INTRODUCTION AND LITERATURE REVIEW An EPD (Environmental Product Declarations) is a third ‐ party certified label that discloses the quantified environmental impacts of producing a product. • Primary energy (MJ) • Global warming potential • Ozone depletion • Acidification potential etc. NAPA EPD Program http://www.asphaltpavement.org/EPD

INTRODUCTION AND LITERATURE REVIEW • Hansen and Copeland (2014) • In 2014, the use of RAP/RAS on U.S. roads displaced 20M barrels of oil and 68M tons of aggregate • A savings of $2.8B based on binder cost of $550/ton and aggregate cost of $9.50/ton • NCAT – Willis (2015) • Utilizing recycled asphalt results in a 9 ‐ 26% energy savings and a 5 ‐ 29% reduction in CO 2 emissions • A 19 ‐ 42% energy savings and a 6 ‐ 39% reduction in CO 2 emissions were realized when using RAP along with locally sourced materials

INTRODUCTION AND LITERATURE REVIEW HOW CAN WE INCREASE RAP CONTENT? • Softer virgin binder grade (binder ‐ grade bumping) • Increased binder content • Recycling agents • Polymer and rubber modifiers • Warm mix asphalt

O UTLINE • I NTRODUCTION AND L ITERATURE REVIEW • E XPERIMENT TYPES • O BJECTIVES AND E XPERIMENTAL PLAN • B INDER GRADE AND BINDER CONTENT • B LENDING EVALUATION • I NITIAL RESULTS • S UMMARY

EXPERIMENTS USED IN THIS STUDY S EMI C IRCULAR B END T EST

EXPERIMENTS USED IN THIS STUDY S EMI C IRCULAR B END T EST – O UTPUT PARAMETERS 3.0 Brittle mix 2.5 2.0 Load (kN) 1.5 1.0 Ductile mix 0.5 0.0 0.0 1.0 2.0 3.0 4.0 Displacement (mm)

EXPERIMENTS USED IN THIS STUDY S EMI C IRCULAR B END T EST – O UTPUT PARAMETERS Fracture energy: is calculated by dividing the work of fracture (the area under the load vs. the average load-line displacement curve) by the ligament area (the product of the ligament length and the thickness of the specimen) of the test specimen prior to testing. Flexibility index: is calculated by dividing the fracture energy by the slope at the inflection point.

EXPERIMENTS USED IN THIS STUDY S EMI C IRCULAR B END T EST – O UTPUT PARAMETERS 3.0 Brittle mix 2.5 2.0 Load (kN) 1.5 1.0 Ductile mix 0.5 0.0 0.0 1.0 2.0 3.0 4.0 Displacement (mm)

EXPERIMENTS USED IN THIS STUDY S EMI C IRCULAR B END T EST – O UTPUT PARAMETERS 3.0 Brittle mix 2.5 2.0 Load (kN) 1.5 1.0 Ductile mix 0.5 0.0 0.0 1.0 2.0 3.0 4.0 Displacement (mm)

EXPERIMENTS USED IN THIS STUDY B EAM F ATIGUE T EST

EXPERIMENTS USED IN THIS STUDY D YNAMIC M ODULUS AND FLOW NUMBER TESTS Dynamic modulus: Determine mix stiffness at different temperatures and load frequencies Conduct flow number experiment at high temperatures to determine rutting resistance

EXPERIMENTS USED IN THIS STUDY W HICH E XPERIMENT IS THE B EST ? ODOT Research Project: Adjusting Asphalt Mixes for Increased Durability and Implementation of a Performance Tester to Evaluate Fatigue Cracking of Asphalt Concrete Experiments evaluated in ODOT-OSU research: SVECD, SCB, IDT, Beam fatigue

EXPERIMENTS USED IN THIS STUDY P RELIMINARY SCB T EST R ESULTS F ROM ODOT C RACKING P ROJECT 1.2 9 SCB tests per section 1. Fracture Energy (kJ/m2) 1.0 2. 3. 0.8 0.6 4. 0.4 0.2 0.0 OR99EB OR99W OR99 ‐ J. City OR22 ‐ Subli. NO Cracking NO Cracking ODOT PMS Cracked Cracked

EXPERIMENTS USED IN THIS STUDY P RELIMINARY SCB T EST R ESULTS F ROM ODOT C RACKING P ROJECT 40 1. 9 SCB tests per section 35 30 Flexibility Index 25 2. 20 15 3. 10 4. 5 0 OR99EB OR99W OR99 ‐ J. City OR22 ‐ Subli. NO Cracking NO Cracking ODOT PMS Cracked Cracked

O UTLINE • I NTRODUCTION AND L ITERATURE REVIEW • E XPERIMENT TYPES • O BJECTIVES AND E XPERIMENTAL PLAN • R AP CONTENT , B INDER GRADE , AND BINDER CONTENT • B LENDING EVALUATION • I NITIAL RESULTS • S UMMARY

O BJECTIVES R AP CONTENT , B INDER GRADE , AND BINDER CONTENT • Identify the effects of binder-grade bumping and higher binder content on RAP/RAS performance • Determine the impact of these alternatives on increasing RAP/RAS contents • Evaluate the effect of blending on mixture performance • Evaluate the cost and benefits of using binder-grade bumping and higher binder content to increase RAP/RAS.

E XPERIMENTAL P LAN R AP CONTENT , B INDER GRADE , AND BINDER CONTENT Phase I – High RAP mixes: RAP Binder Air-void Total Test type Binder grade Replicates content content content Tests PG58-34 6.0% Beam 30% PG64-22 6.4% 7% 3 54 fatigue 40% PG76-22 6.8% PG58-34 6.0% 30% SCB PG64-22 6.4% 7% 4 72 40% PG76-22 6.8% PG58-34 6.0% Dynamic 30% PG64-22 6.4% 7% 2 36 modulus 40%. PG76-22 6.8% PG58-34 6.0% Flow 30% PG64-22 6.4% 7% 2 36 number 40%. PG76-22 6.8%

E XPERIMENTAL P LAN R AP CONTENT , B INDER GRADE , AND BINDER CONTENT Phase II – Low – No RAP and RAP ‐ RAS mixes: RAP Binder Air-void Total Test type Binder grade Replicates content content content Tests 0% Beam PG58-34 6.0% 15% 7% 3 36 PG76-22 fatigue 6.8% RAP/RAS 0% PG58-34 6.0% SCB 15% 7% 4 48 PG76-22 6.8% RAP/RAS 0% Dynamic PG58-34 6.0% 15% 7% 2 24 PG76-22 modulus 6.8% RAP/RAS Flow PG58-34 15% 6.0% 7% 3 24 number PG76-22 RAP/RAS 6.8%

B LENDING EVALUATION Phase III – Blending Evaluation: Image: Zhao et al. (2016) Materials and Design

B LENDING EVALUATION Phase III – Blending Evaluation: RAP Mix RAP Total Blending Repl. Test type mixing Type Content Tests temp. 0% 15% Actual SCB PG58-34 2 temps 4 64 40% 50% 100%

B LENDING EVALUATION Phase III – Blending Evaluation: Binder extraction Binder recovery

B LENDING EVALUATION Phase III – Blending Evaluation: Image: Zhao et al. (2016) Materials and Design

B LENDING EVALUATION Phase III – Blending Evaluation: Theoretical curve Flexibility Index 50 100 0 Actual blending Blending (%)

O BJECTIVES AND E XPERIMENTAL PLAN • A total of 364 experiments • All Phase I samples prepared • Majority of Phase I experiments completed • Phase II samples are currently being prepared • SCB RESULTS FROM PHASE I

O UTLINE • I NTRODUCTION AND L ITERATURE REVIEW • E XPERIMENT TYPES • O BJECTIVES AND E XPERIMENTAL PLAN • R AP CONTENT , B INDER GRADE , AND BINDER CONTENT • B LENDING EVALUATION • I NITIAL RESULTS • S UMMARY

I NITIAL T EST R ESULTS – SCB – F RACTURE E NERGY 1.6 PG58 ‐ 34 PG64 ‐ 22 1.4 Fracture energy (kJ/m2) PG76 ‐ 22 1.2 1 0.8 0.6 0.4 0.2 0 30%RAP ‐ 6%AC 30%RAP ‐ 6.4%AC 30%RAP ‐ 6.8%AC 40%RAP ‐ 6%AC 40%RAP ‐ 6.4%AC 40%RAP ‐ 6.8%AC

I NITIAL T EST R ESULTS – SCB – F LEXIBILITY I NDEX 25 Perfect but what PG58 ‐ 34 about rutting? PG64 ‐ 22 20 PG76 ‐ 22 Flexibility Index 15 10 Limit for acceptance? 5 0 30%RAP ‐ 6%AC 30%RAP ‐ 6.4%AC 30%RAP ‐ 6.8%AC 40%RAP ‐ 6%AC 40%RAP ‐ 6.4%AC 40%RAP ‐ 6.8%AC

O UTLINE • I NTRODUCTION AND L ITERATURE REVIEW • E XPERIMENT TYPES • O BJECTIVES AND E XPERIMENTAL PLAN • R AP CONTENT , B INDER GRADE , AND BINDER CONTENT • B LENDING EVALUATION • I NITIAL RESULTS • S UMMARY

S UMMARY • SCB and Flexibility Index are promising • Sample preparation and testing will be completed soon • MEPDG modeling and cost analysis will follow • Planning to repeat Phase I SCB experiments with specimens aged with new long-term aging protocols (6-7 days of aging loose-mix at 85 o C) • Do mix designs for critical mixes

GO BEAVS! Q & A Thank you! This study is sponsored by Oregon Department of Transportation (ODOT). This funding is gratefully acknowledged.