Asphalt ETG Update. Technical Discussion & Input. Asphalt Expert Task Groups. Asphalt Binder ETG Activities. MSCR Implementation Efforts

Transcription

1 SEAUPG ANNUAL MEETING SESSION VII-ASPHALT BINDERS NOVEMBER 15, 2012 Asphalt Expert Task Groups Provide a forum for Government, Industry, and Academia in the discussion of ongoing asphalt binder and mixture technology and to provide technical input for current and future research, development, and specifications. Asphalt ETG Update Jeff Withee Materials Team FHWA Office of Pavement Technology 2 1 Asphalt Expert Task Groups Asphalt Mixture & Construction ETG Most recent meeting September, 2012 Asphalt Binder ETG Most recent meeting September, 2012 Warm Mix Asphalt TWG July, 2012 Final Meeting High RAP/RAS ETG July, 2012 Final Meeting Pavement Sustainability TWG April at UC Davis in Sacramento, CA Technical Discussion & Input Open Meetings All are Welcome! 4 MSCR Implementation Efforts Asphalt Binder ETG Activities Multiple Stress Creep Recovery Specifications TP 70 MSCR Test of Asphalt Binder Using DSR Performance Graded Asphalt Binder Using MSCR GTR within the PG System Update AASHTO Test Standards AASHTO SOM Status 5 Regional workshops AI / FHWA AI/FHWA/AMRL testing Precision & Bias Developing user literature AI / FHWA User Producer Groups round robin repeatability testing (NE & SE) 6

2 Ground Tire Rubber, GTR GTR blending study size, source, % Evaluate GTR modified binders to PG and MSCR specifications Potential crude source dependency GTR size will effect test results Particles should 1 mm size or less in DSR DSR fixture change Careful formulation is needed to meet all J nr specs but it can be done successfully AI and the FHWA FHWA is working with the Asphalt Institute to assist States to effectively understand and implement MSCR & better understand GTR utilization. Michael Anderson 8 Asphalt Binder ETG Activities Lab Mixing & Compaction Temperatures Binder Thermal Cracking Test DSR Test Standards Updates and clarifications Temperature equilibrium Asphalt Mix ETG Activities Asphalt Mixture Performance Tester Mix Design Manual NCHRP 9 33 RAP / RAS WMA Update AASHTO Test Standards AASHTO SOM Status 9 10 Asphalt Mix Performance Tester Refined under NCHRP 9 29 Provides input (MEPDG) Dynamic Modulus E* and Flow (Fn) AASHTO PP 60, TP 79, PP 61 Flow Number standardization Fatigue Testing protocols AMPT Pooled Fund Study Objectives o Procure AMPT for highway agencies o Provide training on AMPT o Support national AMPT implementation Progress and Schedule o 24 AMPTs delivered, 1 on order o Training courses (6) completed/materials available o Held National Pooled Fund Workshop o 2012/2013 E* and Flow Number ILS NE & SE o 2013 Western Pooled Fund Workshop Pooled Fund Implementation 11

3 AMPT Pooled Fund Study TPF-5(178) NCAT and FHWA FHWA is working with NCAT (Cooperative Agreement) to assist States to effectively address flexible pavement challenges in AMPT & FHWA POC: Jeff Withee (HQ) 13 Nam Tran Mix Design Manual NCHRP 9 33 (AAT) & 9 33A (ASU) Report: A Manual for Design of Hot Mix Asphalt with Commentary Adapting Specification Criteria for Simple Performance Tests to HMA Mix Design Performance Test Criteria 9 33 maintain existing N design criteria Proposed Specification: to be used as a preliminary selection of mix parameters as a starting point for mix testing RAP/RAS ETG Key Activities Guidance on use of High RAP Guidance on RAS Usage Propose Research Needs Update AASHTO Test Standards Input to SOM Website: Current Guidelines AASHTO M 323 Standard Specification for Superpave Volumetric Mix Design RAP % Based on % Binder Historically, Agency limit RAP based on % by weight of total mix need change to M 323? With high RAP contents, the primary issue is impact on binder properties Determine contribution of RAP binder toward total binder in the mix, by weight Example, 70% of binder content must be virgin or no more than 30% binder content can come from RAP or RAP & RAS 17 18

4 NCHRP 9 46 Mix Design and Evaluation Procedure for High Reclaimed Asphalt Pavement Content in HMA Develop mix design method & specification for Mixes containing up to 50% RAP Test method for measuring properties of composite binder, test mix back calculate binder properties Specification for RAP quality and processing RAP/RAS ETG Key Activities Usage: NAPA Member Survey Performance of Recycled Asphalt Shingles in Hot Mix Asphalt Pooled Fund Study Best practices for using RAS in Mixes with focus on material properties & mixture performance WMA TWG Initiatives Participants FHWA, MO, IA, MN, IN, and CO Also QC/QA concerns, demo projects, performance database search TPF-5(213) 21 NCHRP 9 43 (Compete) AAT Mix Design Practices for Warm Mix Asphalt Summary of Changes Appendix to AASHTO R 35 Standard Practice for Superpave Volumetric Design for HMA Specimen Fabrication Procedures Recommended Binder Grade Changes Based on Production Temperature (Binder ageing index) Coating Evaluated at Production Temperature Rutting Resistance Evaluated for 3 Million ESAL or Greater Forwarded to Subcommittee on Materials otp 70 (MSCR) data sampling cycles odsr additional gap spacing criteria to accommodate GTR odraft Standard for Linear Amplitude Sweep Test for DSR odraft Appendix TP 79 (AMPT) for HMA/WMA Flow Number (Fn) criteria odraft Standard for Troubleshooting Asphalt Specimen Volumetric Differences between SGC Used in Design and Field Management 2010 Beyond 23 of 94

5 Beyond Action Items September 2012 Meetings oreview of Jnr Criteria for Unmodified Asphalt Binder omscr Recovery: Possible AASHTO Procedure oreview of Cooling Medium Effects on BBR Results olinear Amplitude Sweep Test Ruggedness odraft Standard for AMPT Direct Tension Cyclic Fatigue Test odraft Standard for Low Temperature Fracture Energy Test Using the Semi-Circular Bend Geometry (SCB) oidt E* Ruggedness Testing omoisture Induced Sensitivity Test (MIST) owma Workability and Field Compaction Temperatures oanalysis of PP 53 Methodology to Determine Asphalt Availability FHWA Field Support Mobile Lab Pavement Website Mobile Asphalt Pavement Materials Lab Site Visit Field Data/Testing Use/Demo Emerging Test Devices POC: Matthew Corrigan 29