Use of Reclaimed Asphalt Pavement and Recycled Asphalt Shingles in Asphalt Mixtures (2016)

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104 NCHRP 46-05—RAP and RAS—Materials Engineers Introduction Standard laboratory practices and procedures have been developed and/or adapted in order to handle, mix, and test these mixtures within each agency. The main focus of this survey is to document mix design and testing experiences of those folks by actually working with high RAP, RAS, or RAP/RAS combinations in the laboratory. Survey organization: • Determining the asphalt content • Determining the binder grade • Determining aggregate properties • Preparing materials for mixing and compaction • Compaction and long-term aging • Volumetric testing • Durability and performance testing Please provide your contact information. First Name: _________________________________________________ Last Name: _________________________________________________ Agency: _________________________________________________ State: _________________________________________________ E-mail Address: _________________________________________________ Phone Number: _________________________________________________ Determining the Asphalt Content 1. For the purposes of mix designs, indicate which “philosophy” is used to establish the contribution of the recycled material asphalt. Comments: 2. Indicate which equation(s) is (are) used to calculate the total binder content of the mixture and/or limit the percent of recycled asphalt in the total asphalt content. 2.a. We use the sum of the new asphalt and recycled asphalt material content: Total asphalt content = (RAP asphalt content %) (% of RAP in mixture) + (RAS asphalt content %) (% of RAS in mixture) + (new asphalt content %) ( ) Yes ( ) No Comments: Material 100% Available for Mix 0% (“Black Rock”) Agency-Assumed Percentage of the Total Recycled Asphalt Content 25% or Less RAP More than 25% RAP RAS, manufacturer waste RAS, tear-offs RAS, any combination RAP and RAS combination APPENDIX A State Materials Engineer Survey

105 2.b. We use the asphalt binder ratio (ABR) equation: ABR = (New asphalt %) / (Total asphalt %) ( ) Yes ( ) No We use a minimum ABR value of: ____________________________________ 2.c. We use the recycled binder ratio (RBR) RBR = (Recycled binder content %) / (Total binder content %) ( ) Yes ( ) No We use a maximum RBR value of: ______________________________ 2.d. If you do not use either ABR or RBR, briefly describe how the total binder content is calculated. 2.e. Is a reduction factor applied to recycled asphalt content? That is, do you correct for the likelihood that not all of the recycled binder content is actually incorporated into the total effective asphalt content of the mixture? 3. Preparation of recycled material before testing 3.a. If material is dried to a constant mass, indicate the variables used to determined “constant mass.” 3.b. Maximum percent change between consecutive weighings: 3.c. Time between consecutive weighings: 3.d. Drying method (e.g., oven, counter under fan, etc.): 3.e. At what temperature: 4. The asphalt content of the recycled materials is determined for: (Check all that apply.) ( ) RAP (not fractionated) ( ) Coarse RAP fraction ( ) Fine RAP fraction ( ) RAS ( ) RAP and RAS combined prior to testing ( ) Other (please explain in comment box below): Comments: 5. If you separate RAP into coarse and fine fractions for testing, please indicate which sieve size is used for “retained on” / “percent passing.” ( ) 4.75-mm (No. 4) ( ) 2.36-mm (No. 8) 6. If you use solvent extraction to determine the recycled binder content, indicate which method(s) is (are) used. Comments: Materials Is the recycled material dried prior to using to prepare mix design samples? What method of drying is used? What temperature is used for drying? How long is sample dried? Yes No Under fan at room temperature Oven oC oF Hours, max. Until constant mass RAP RAS Materials Solvent Extraction Centrifuge Solvent Extraction Reflux Solvent Extraction Vacuum Extraction Vessel, AASHTO Soaking (non- standard option) RAP, unfractionated Coarse RAP fraction Fine RAP fraction RAS RAP and RAS combination

106 6.a. And indicate which solvent(s) is (are) used. Comments: 7. Indicate when the ignition oven is used and how materials other than asphalt and aggregate are considered. 7.a. Do you use the ignition oven to determine the recycled material asphalt content? 7.b. If a correction factor is used, what value(s) do you use? 7.c. If you use the ignition oven method for testing shingles, how do you correct for burning off any paper (backing, roofing felt, etc.) products? Comments: Determining the Binder Grade 8. Indicate if you recover the recycled material binder for any of the following. (Check all that apply.) 9. Which recovery methods(s) do you use? (Check all that apply.) ( ) Abson (AASHTO T170) ( ) Rotavapor (ASTM D5404) ( ) Combination Extraction / Recovery (AASHTO T319) Comments: Materials Trichloroethylene (TCE) n-Propyl Bromide (nPB) Toluene Toluene and Ethanol Blend RAP Coarse RAP fraction Fine RAP fraction RAS RAP and RAS combination Materials Yes No Sometimes, depending on aggregate type RAP, unfractionated Coarse RAP fraction Fine RAP fraction RAS RAP and RAS combination Materials 5% or Less Recycled Material 15% or Less Recycled Material 25% or Less Recycled Material More than 25% Recycled Material RAP, unfractionated Coarse RAP fraction Fine RAP fraction RAS RAP and RAS combination

107 10. Virgin PG grade adjustment based on various percentages of individual recycled materials. Please indicate how your agency determines the virgin PG grade used in mixtures with recycled materials by: Comments: 11. Indicate which binder tests you use to determine the true (continuous) recycled binder grade. ( ) As-recovered high binder temperature (DSR, AASHTO T315) ( ) Condition recovered binder in rolling thin film oven (AASHTO T240) ( ) RTFOT high binder temperature (DSR, AASHTO T315) ( ) RTFOT intermediate binder temperature (DSR, AASHTO T315) ( ) RTFOT low binder temperature for m-value (Bending beam rheometer, AASHTO T313) ( ) RTFOT low binder temperature for stiffness (Bending beam rheometer, AASHTO T313) ( ) RTFOT + PAV intermediate binder temperature (DSR, AASHTO T315) ( ) RTFOT + PAV low binder temperature for stiffness (Bending beam rheometer, AASHTO T313) ( ) RTFOT + PAV low binder temperature for m-value (Bending beam rheometer, AASHTO T313) Comments: 12. Indicate which approach is used to ensure the blended binder meets the required PG grade. ( ) Establish (select) percent of RAP to be used, then determine the virgin asphalt PG grade needed ( ) Choose virgin asphalt PG to be used, then determine the percent of recycled material ( ) Use softening or rejuvenator additive to soften the recycled material binder, then proceed with determining the virgin asphalt PG Comments: 13. If you use softening and/or rejuvenating additive (e.g., flux oil, proprietary product, etc.) to modify stiffer and aged recycled binder indicate the product(s) you use. Determining Aggregate Properties 14. This question collects information about sieving (fractionating) dry materials (aggregates, RAP, shingles) for batching mix design samples. 14.a. Does the percent or type of recycled materials used in the mixture change how you fractionate, or don’t fractionate, the materials in the laboratory? Comments: Materials Upper PG Temperature Lower PG Temperature Bump one grade lower Bump two grades lower Determine true grade with testing Bump one grade lower Bump two grades lower Determine true grade with testing 15% or less RAP 25% or less RAP 15%< RAP More than 25% RAP More than 50% RAP 5% or less RAS More than 5% RAS RAP and RAS combination Materials Yes No Sometimes 25% or less RAP More than 25% RAP Shingles, manufacturer waste Shingles, tear-offs Shingles, combination RAP and RAS

108 14.b. Indicate which individual sizes and/or percent retained on a given sieve size are used for batching coarse particles when using various percentages and types of materials in the mixture. Comments: 14.c. Indicate what individual sizes and/or percent passing a given sieve are used for batching fine particles when using various percentages and types of materials. Comments: 15. Indicate when the aggregate properties of the individual recycled materials need to be determined. ( ) 15% or less RAP ( ) 25% or less RAP ( ) More than 25% RAP ( ) RAS, manufactured waste ( ) RAS, tear-offs ( ) RAS, combination ( ) RAP and RAS combination ( ) We test aggregates for the mixture (after solvent extraction or ignition oven) rather than individual recycled aggregate properties Comments: Materials 25-mm (1-in) 12.5- mm (1/2-in) 9.5-mm (3/8-in) 4.75-mm (No. 4) 2.36- mm (No. 8) Retained on 4.75- mm (No. 4) Retained on 2.36- mm (No. 8) Aggregates 25% or less RAP 25% or more RAP Shingles, manufacturer waste Shingles, tear-offs Shingles, combination RAP and RAS Materials Passing 4.75-mm (No. 4) Passing 2.36-mm (No. 8) 1.18- mm (No. 16) 0.6-mm (No. 30) 0.30- mm (No. 50) 0.15-mm (No. 100) 0.075- mm (No. 200) Aggregates 25% or more RAP More than 25% RAP Shingles, manufacturer waste Shingles, tear-offs Shingles, combination RAP and RAS

109 16. Indicate which test methods are used to determine the specific gravities of the recycled materials aggregate. For clarification: When the maximum specific gravity is measured, the effective specific gravity (Gse) is calculated, then used to estimate the bulk specific gravity (Gsb). 17. Indicate the aggregate specification tests used to determine the recycled material aggregate properties. (Check all that apply.) Comments: 18. Mix design calculations require a number of individual material properties. If your agency assumes, rather than measures, any of the properties in the table below, please enter the typical estimated values in the appropriate text boxes. Materials Bulk Specific Gravity (AASHTO T166) after Solvent Extraction Bulk Specific Gravity (AASHTO T166) after Ignition Oven We Estimate Bulk Specific Gravity Based on Experience Theoretical Maximum Specific Gravity (AASHTO T209) RAP, unfractionated Coarse RAP fraction Fine RAP fraction RAS RAP and RAS combination Materials Flat and Elongated (ASTM D4791) Fractured Faces (ASTM D5821) Fine Aggregate Angularity (AASHTO T304) Sand Equivalent (AASHTO T176) Minus 0.075-mm (No. 200) by Washing Gradation (sieve analysis) RAP, after solvent extraction RAP, after ignition oven RAS, after solvent extraction RAS, after ignition oven Only determine properties for entire mixture with the recycled materials after either solvent or ignition oven testing. Materials Binder absorbed by recycled material aggregates Recycled material asphalt specific gravity Virgin asphalt specific gravity RAP, unfractionated Coarse RAP fraction Fine RAP fraction RAS RAP and RAS combination

110 19. Indicate the aggregate source property tests that are conducted on the recycled material aggregates. (Check all that apply.) Comments: Preparing Materials for Mixing and Compaction 20. This question collects information on how materials are heated for mixing. 20.a. Indicate how the materials are, or are not, combined for heating. Comments: 20.b. Indicate how you know the material is at required temperature for mixing. 20.c. Indicate the maximum allowable heating time for each material before mixing. Aggregate: RAP: RAS: Combination of RAP and RAS: 20.d. Indicate the units preferred for temperature choices: ( ) Celsius ( ) Fahrenheit Material LA Abrasion (toughness) Micro- Deval (toughness) Sodium Sulfate Soundness Magnesium Sulfate Soundness Assume Source Properties Are OK if RAP Came from State Highway Project RAP, after solvent extraction RAP, after ignition oven RAS, after solvent extraction RAS, after ignition oven We determine properties for entire mixture after either solvent or ignition oven testing. Materials Heated Separately Combined and Heated Together Aggregate and RAP Aggregate and RAS RAP Fractions RAS Fractions RAS with Sand (to avoid clumping) RAP and RAS Materials Based on Time in Oven Temperature Probe in the Material While it Is in the Oven Temperature Measured Immediately After Removing from Oven Aggregates RAP RAS Combined RAP and RAS

111 20.e. Indicate the temperature used to heat each material before mixing. Aggregates RAP RAS Combined RAP and RAS 20.f. Indicate the temperature used to heat materials before mixing. Aggregates RAP RAS Combined RAP and RAS 22. In what order are materials added to the mixing bowl, and how long is the material mixed before adding additional materials? 23. Indicate the time and temperature used for short-term aging of the loose mixture. Compaction and Long-term Aging 24. Enter the typical number of gyration(s) (Ndesign) which is (are) used to compact recycled material mixtures in the text boxes. Comments: 25. If used, enter time and temperatures used for long-term aging of the compacted samples. Comments: Materials Added to Bowl Mixing Time Aggregates, all Fraction (sieve sizes) RAP, Coarse RAP, Fine RAS Asphalt Rejuve nator Asphalt and rejuvenator preblended prior to start of mixture design sample prep 1 min. 2 min. visual inspection of uniformity Materials Short-Term Aging Time, Hours Temperature Units Celsius Fahrenheit Mix with RAP Mix with RAS Mix with RAP and RAS Materials Wear Course Dense Mix Binder Course Base Course SMA Pervious/Permeable Mixtures 25% or less RAP mixtures More than 25% RAP mixtures RAS mixtures RAP and RAS combination mixtures Materials Long-Term Aging Time, Hours Temperature Units Celsius Fahrenheit 25% or less RAP samples More than 25% RAP samples RAS mixtures RAP and RAS combination mixtures

112 Volumetric Testing 26. Indicate if it more difficult to meet volumetric requirements when mixtures contain various amounts and types of recycled materials. Comments: Durability and Performance Based Testing 27. Rutting: If you evaluate the rutting potential of mixes in your lab, please indicate which method(s) you use (Choose all that apply.) Comments: 28. Mix Stiffness: If you evaluate mixture stiffness in your lab, please indicate which method(s) you use (Choose all that apply.) Comments: Materials Check the box if it is more difficult to obtain acceptable properties when compared with similar mixtures without any recycled material content. 25% or less RAP More than 25% RAP RAS mixtures RAP and RAS combination mixtures Air Voids, % VMA, % VFA, % Dust to Asphalt Ratio Used routinely for our mix designs Use when approving changes in materials during construction Use for research studies Asphalt Pavement Analyzer (APA) Hamburg Rut Tester Wet Rut Testing to Determine Stripping Inflection Point Asphalt Mixture Performance Test (AMPT) Dynamic Modulus Flow Number Flow Time Testing Used routinely for our mix designs Use when approving changes in materials during construction Use for research studies Resilient Modulus at a single temperature Resilient Modulus at several temperatures Dynamic Modulus at a single temperature Dynamic Modulus over a range of temperatures to develop a master curve

113 29. Cracking (Non-Thermal): If you evaluate cracking potential of mixtures in your lab, please indicate which method(s) you use. (Choose all that apply.) Comments: 30. Thermal Cracking: If you evaluate the thermal cracking potential of mixtures in your lab, please indicate which method(s) you use (Choose all that apply.) Comments: 31. All Cracking Testing: If you evaluate any type of cracking potential, what temperature or temperatures do you use? Comments: 32. Rutting Potential: Based on your experience, indicate your level of agreement with the following statements. Comments: Testing Used routinely for our mix designs Use when approving changes in materials during construction Use for research studies Fatigue cracking, bending beam (AASHTO T321) Overlay tester Disc-Shaped Compact (DCT) Tension Test (ASTM D7313) Semi Circular Bend (SCB) Test Testing Used routinely for our mix designs Use when approving changes in materials during construction Use for research studies Indirect Tensile Strength (AASHTO T322) Semi-Circular Bend (SCB) Test Disc-Shaped Compact (DCT) Tension Test (ASTM D7313) Testing High Temperature (summer temperatures) Intermediate (around ambient) Low Temperature (winter temperatures) Bending Beam Fatigue Overlay Tester Disc-Shaped Compact (DCT) Tension Test (ASTM D7313) Semi Circular Bend (SCB) Test Statement Strongly Agree Agree Neutral Disagree Strongly Disagree Rutting potential is increased with increasing percentages of recycled RAP Rutting potential is increased with increasing percentages of recycled shingles Rutting potential is increased with a combination of RAP and RAS

114 33. Cracking Potential (Non-Thermal Cracking) Potential: Based on your experience, indicate your level of agreement with the following statements. Comments: 34. Thermal Cracking Potential: Based on your experience, indicate your level of agreement with the following statements. Comments: 35. Mix Durability Potential: Moisture sensitivity (TSR) and indirect tensile strength: Based on your experience, indicate your level of agreement with the following statements. Statement Strongly Agree Agree Neutral Disagree Strongly Disagree Cracking potential is increased with increasing percentages of recycled RAP Cracking potential is increased with increasing percentages of recycled shingles Cracking potential is increased with a combination of RAP and RAS Statement Strongly Agree Agree Neutral Disagree Strongly Disagree Thermal cracking potential is increased with increasing percentages of recycled RAP Thermal cracking potential is increased with increasing percentages of recycled shingles Thermal cracking potential is increased with a combination of RAP and RAS Strongly Agree Agree Neutral Disagree Strongly Disagree Moisture sensitivity is increased with increasing percentages of recycled RAP Moisture sensitivity is increased with increasing percentages of recycled shingles Moisture sensitivity is increased with a combination of RAP and RAS Indirect tensile strength is increased with increasing percentages of recycled RAP Indirect tensile strength is increased with increasing percentages of recycled shingles Indirect tensile strength is increased with a combination of RAP and RAS