Use of Recycling Agents in Asphalt Concrete Mixtures (2022)

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89   A P P E N D I X B Agency Survey Responses (DOTs) The DOTs’ responses are presented in this appendix. Block 1: The questions in this section are designed to determine the current status of the use of RAM including RAP and RAS in asphalt mixtures at your agency. Question 1: Does your agency currently allow the use of RAM in asphalt mixtures? Select all that apply: Use of RAP only Use both of RAP and RAS AL; AZ; CA; CO; CT; FL; HI; ID; LA; ME; MA; MS; NE; NV; NH; NM; ND; OK; RI; UT; WY AK; AR; DE; GA; IL; IN; IA; KS; MD; MI; MN; MO; MT; NJ; NY; NC; OH; OR; PA; SC; TN ; TX; VT; VA; WA; WI Question 2: Does your agency currently allow the use of RAs in asphalt mixtures with RAM? Select all that apply: RAs are addressed in the specifications and/or listed on the APL/QPL RAs are used for demo/research purposes RAs are addressed in the specifications and/or listed on the APL/QPL and RAs are used for demo/research purposes Not allowed AR; DE; MO; WA CA; GA; KS; LA; MS; NE; OH; OK; PA; TN; TX; VA; WI NJ; OR AL; AK; AZ; CO; CT; FL; HI; ID; IL; IN; IA; ME; MD; MA; MI; MS; MT; NV; NH; NM; NY; NC; ND; RI; SC; UT; VT; WY

90 Use of Recycling Agents in Asphalt Concrete Mixtures By total RAM content By RAP content and RAS content separately Both methods are used MN; OR AR; DE; GA; OH; PA; WA KS; MO; NJ; TN; TX; VA; WI Question 4: What is the typical RAM content (with both RAP and RAS), in terms of RBR, used by your agency in surface (or wearing) course asphalt mixtures? Select best option: <0.1 0.1–0.15 0.15–0.2 0.2–0.3 >0.3 Not allowed NJ; TN; TX WI KS; MN; MO; OR; VA Question 5: What is the maximum RAM content (with both RAP and RAS), in terms of RBR, used by your agency in surface (or wearing) course asphalt mixtures? Select best option: <0.1 0.1–0.15 0.15–0.2 0.2–0.3 >0.3 TX TN KS; MN; OR; VA; WI; MO Question 6: What is the typical RAM content (with both RAP and RAS), in terms of RBR, used by your agency in non-surface asphalt mixtures? Select best option: <0.1 0.1–0.15 0.15–0.2 0.2–0.3 >0.3 KS; MN; MO; OR; TN; TX; VA; WI Question 7: What is the maximum RAM content (with both RAP and RAS), in terms of RBR, used by your agency in non-surface asphalt mixtures? Select best option: <0.1 0.1–0.15 0.15–0.2 0.2–0.3 >0.3 KS; MN; OR; TX; VA MO (0.5); TN (0.35) Question 3: How does your agency specify RAM content in asphalt mixtures?

Agency Survey Responses (DOTs) 91   Question 8: Does your agency have different criteria, in terms of RAP content in asphalt mixtures, for fractionated and non-fractionated RAP? Yes No CA; LA; TN AR; DE; GA; KS; MO; NE; NJ; OH; OK; PA; TX; VA; WA; WI Question 9: What is the typical RAP content, in terms of RBR, used by your agency in surface (or wearing) course asphalt mixtures? Select best option: <0.1 0.1–0.15 0.15–0.2 0.2–0.3 >0.3 Not Allowed AR OH; PA; TX GA; WA; WI DE; KS; MO; NE; VA – OK Question 10: What is the maximum RAP content, in terms of RBR, used by your agency in surface (or wearing) course asphalt mixtures? Select best option: <0.1 0.1–0.15 0.15–0.2 0.2–0.3 >0.3 AR TX GA; OH KS; NE; VA WI; DE (0.4); MO (0.5); PA (0.32); WA (0.4) Question 11: What is the typical RAP content, in terms of RBR, used by your agency in non-surface asphalt mixtures? Select best option: <0.1 0.1–0.15 0.15–0.2 0.2–0.3 >0.3 AR WI GA; OH DE; KS; NE; MO; OK; TX; VA OH (0.42); WA Question 12: What is the maximum RAP content, in terms of RBR, used by your agency in non-surface asphalt mixtures? Select best option: <0.1 0.1–0.15 0.15–0.2 0.2–0.3 >0.3 AR – – GA; KS; NE; OK; TX; VA DE (0.4); OH (0.42); MO (0.5); OH; PA (0.51); WA (0.4) Question 13: What is the typical fractionated RAP content, in terms of RBR, used by your agency in surface (or wearing) course asphalt mixtures? Select best option: <0.1 0.1–0.15 0.15–0.2 0.2–0.3 >0.3 Not Allowed – TN LA CA – –

92 Use of Recycling Agents in Asphalt Concrete Mixtures Question 14: What is the maximum fractionated RAP content, in terms of RBR, used by your agency in surface (or wearing) course asphalt mixtures? Select best option: <0.1 0.1–0.15 0.15–0.2 0.2–0.3 >0.3 Upload File – – TN CA; LA – – Question 15: What is the typical fractionated RAP content, in terms of RBR, used by your agency in non- surface asphalt mixtures? Select best option: <0.1 0.1–0.15 0.15–0.2 0.2–0.3 >0.3 – – – CA; LA; TN – Question 16: What is the maximum fractionated RAP content, in terms of RBR, used by your agency in non- surface asphalt mixtures? Select best option: <0.1 0.1–0.15 0.15–0.2 0.2–0.3 >0.3 Upload File – – – CA; LA TN (O.35) – Question 17: What is the typical non-fractionated RAP content, in terms of RBR, used by your agency in surface (or wearing) course asphalt mixtures? Select best option: <0.1 0.1–0.15 0.15–0.2 0.2–0.3 >0.3 Not Allowed – CA LA – – TN Question 18: What is the maximum non-fractionated RAP content, in terms of RBR, used by your agency in surface (or wearing) course asphalt mixtures? Select best option: <0.1 0.1–0.15 0.15–0.2 0.2–0.3 >0.3 Upload File – CA LA – – – Question 19: What is the typical non-fractionated RAP content, in terms of RBR, used by your agency in non-surface asphalt mixtures? Select best option: <0.1 0.1–0.15 0.15–0.2 0.2–0.3 >0.3 TN CA LA – – Question 20: What is the maximum non-fractionated RAP content, in terms of RBR, used by your agency in non-surface asphalt mixtures? Select best option: <0.1 0.1–0.15 0.15–0.2 0.2–0.3 >0.3 Upload File – CA; TN LA – – –

Agency Survey Responses (DOTs) 93   Question 21: What is the typical RAS content, in terms of RBR, used by your agency in surface (or wearing) course asphalt mixtures? Select best option: <0.05 0.05–0.1 0.1–0.15 0.15–0.2 >0.2 Not Allowed AR; GA; OH; TN; VA; WA – MO; WI DE; KS; PA – NJ; TX Question 22: What is the maximum RAS content, in terms of RBR, used by your agency in surface (or wearing) course asphalt mixtures? Select best option: <0.05 0.05–0.1 0.1–0.15 0.15–0.2 >0.2 Upload File AR; GA; OH TN; WA VA DE; KS; PA MO WI Question 23: What is the typical RAS content, in terms of RBR, used by your agency in non-surface asphalt mixtures? Select best option: <0.05 0.05–0.1 0.1–0.15 0.15–0.2 >0.2 AR; OH; TN; TX; VA; WA 0 MO; WI DE; KS PA (0.22) Question 24: What is the maximum RAS content, in terms of RBR, used by your agency in non-surface asphalt mixtures? Select best option: <0.05 0.05–0.1 0.1–0.15 0.15–0.2 >0.2 Upload File AR TN; WA – DE; KS; TX MO; PA (0.26) OH; VA; WI Block 2: The questions in this section are designed to determine the current status of the use of recycling agents (RAs) in asphalt mixtures by your agency. Question 25: How many years has your agency used RAs in asphalt mixtures with RAM? 1 2 3–5 >5 Unsure GA MN; NE; OH; TX DE; LA; OK; PA; VA KS; WO; MA AR; NJ; OR; TX; WI Question 26: Over that time, approximately how many projects each year have used RAs in asphalt mixtures with RAM? <5 5–10 10–30 30–50 >50 Unsure GA; KS; LA; MN; NE; OH; OK; PA; TN; WA – VA MO DE AR; CA; NJ; OR; TX; WI

94 Use of Recycling Agents in Asphalt Concrete Mixtures Question 27: Approximately what percentage of the total annual tonnage of asphalt mixtures with RAM contains RAs? 1%–5% 5%–10% 10%–15% 15%–20% >20% Unsure KS; MN; NE; OH; OK; TN; TX; WA DE MO – – AR; LA; NJ; OR; PA; VA; WI Question 28: How many different RA products has your agency used in asphalt mixtures with RAM? <3 3–5 5–10 >10 Unsure DE; KS; OH; OK; PA LA; MO; NE; TN; VA MN – GA; NJ; OR; TX; WA; WI Question 29: What type(s) of RA products has your agency used in asphalt mixtures with RAM? Select all that apply under either/both classification systems (source/chemical composition and ASTM D4552 specification): RA0 RA1 RA5 RA25 RA75 RA250 RA500 PA Paraffinic Oils Aromatic Extracts Naphthenic Oils Triglycerides & Fatty Acids Tall Oils Others Unknown LA; NE; VA LA; NE; OK LA; NE LA; NE; VA KS; LA; NE; VA; OK OH; WA AR; DE; MO; LA; NJ; OR; TN; TX; WI Others Not sure chemistry or type of RA, but used an Ingevity and Arizona Chemical products The only two products that have been used by our contractors are Revive 1114 from ARR Maz, and Jive from a company called POET. Question 30: At which point is the RA added during production? Select all that apply: Pre-blended with binder at terminal In-line blending at plant Pretreating of RAP/RAS Other Unknown ME; NE; NJ; OK; OR; WA DE; MN; MO; OH; OK; TN; VA KS; LA; MN; PA; VA AR; TX; WI

Agency Survey Responses (DOTs) 95   Question 31: Does your agency currently use RAs in surface (or wearing) course asphalt mixtures with RAM? Use of RA required Use of RA allowed/optional RAs not used KS AR; DE; MN; MO; NJ; WA CA; LA; NE; OH; OK; OR; PA; TN; TX; VA; WI Question 32: Does your agency currently use RAs in non-surface asphalt mixtures with RAM? Use of RA required Use of RA allowed/optional RAs not used AR; DE; MN; MO; NJ; OK; WA CA; KS; LA; NE; OH; OR; PA; TN; TX; VA; WI Question 33: How are RAs specified in your current material specifications? Select all that apply: Approved/qualified product list Project by project basis Experimental/test sections only Other KS; LA; MO AR; OR CA; MN; NE; OH; OK; PA; TN; TX; VA DE; LA; NJ; WA Others RAs are not specified; optional only. For a research section, the material would be part of the project specification. It is referenced in the high-RAP specification. As needed to meet our PG binder specifications per M 332, including percent recovery. Question 34: Please briefly describe the process/framework to add your RAs to the state official approved/qualified product list (e.g., based on previous successful experience and promising field performance in or outside the state, based on the outcomes of a research effort) or please upload the corresponding documents here or provide links to the documents if applicable: KS Meet specified PG and look at delta Tc LA Test section is constructed for monitoring field performance; laboratory performance indicators are measured for evaluation. MS Based on test results of the final asphalt mixture and satisfactory field performance Other In-line blending when offloading binder from haul unit to storage tank Used in hot-in-place (HIP) recycling projects; added during field recycling Pre-blended with binder at plant Pretreating of RAP/RAS only for research

96 Use of Recycling Agents in Asphalt Concrete Mixtures Other Contractor submits product information with mix design for approval. Based on the scenarios for current modifiers Have not determined details Determined partially by the university research team Contractors get approved after selecting a product. Determined by contractor and asphalt supplier Question 36: What methodology does your agency use or require to determine the RA type? Select all that apply: RA type selection is a function of RBR. RA type is determined using binder testing. MO; NE; OK RA type is determined using mixture testing. LA Other Agency does not have methodology to specify RA type. KS; PA; TX Unknown OR Question 37: At which point in the process is the RA dosage determined? Select all that apply: Material selection NE; NJ; OK; TX Mix design AR; DE; KS; LA; MN; MO; NE; NJ; OH; OK; OR; PA; TN; VA Production KS Other WA (dosage determined in preliminary binder extraction, recovery and testing phase, prior to mix design evaluation and approval) Question 35: Who determines/specifies the RA type in asphalt mixtures with RAM? Select all that apply: Number of Agencies Agency determined KS; LA; NE; OK; OR; PA; TX Contractor determined based on agency requirements LA; MO; PA Contractor determined independently DE; MN; NJ; TN RA determined based on agency requirements 0 RA determined independently OK Other AR; LA; OH; WA; TX; WV Unknown WI

Agency Survey Responses (DOTs) 97   Other Specified a dosage of 2% by weight of virgin binder. Details TBD Question 39: What methodology does your agency use or require to determine the RA dosage? Select all that apply: RA dosage selection is a function of RBR. NE RA dosage is determined using binder testing. MO; NE; OK RA dosage is determined using mixture testing. LA; TN Other KS (specified a dosage of 2% by weight of virgin binder) Agency does not have dosage methodology specified. AR; OR; PA Question 40: At what point in the process is the RA dosage verified? Select all that apply: Mix design approval AR; KS; NE; OK; TE Producer quality control LA Agency quality assurance MO Question 38: Who determines/specifies the RA dosage in asphalt mixtures with RAM? Select all that apply: Agency determined KS; NE; OK Contractor determined based on agency requirements AR; KS; LA; MO; OR; PA; TN; VA; WA Contractor determined independently TX; NJ RA producer determined based on agency requirements RA producer determined independently DE; MN; OK Other KS; OH Unknown WI

98 Use of Recycling Agents in Asphalt Concrete Mixtures Other Monitor the amount pumped out of tote during offload of binder from haul unit to binder storage tank Details TBD RA dosage verified on asphalt supplier’s delivery documentation, bill of lading. Question 42: Are there any changes to your quality assurance (QA) process when RAs are used? Yes No Unsure AR; DE; KS; MN; MO; NE; NJ; OK; OR; PA; TN; VA; WA; WI LA; OH; TX Question 43: What aspect(s) of the QA process are different when RAs are used? Select all that apply: Producer QC testing Producer QC personnel qualification Agency inspection process Agency inspector qualification Agency validation/acceptance testing Unsure N/A Question 41: How is the RA dosage verified? Select all that apply: By binder testing By mixture testing By plant records Other NE; OK; WA TA; VA AR; KS; LA; NE; MO; TN; WA KS; OH; WA Other LA; OH; TN; WA Not verified DE; MN; NJ; OR; PA; TX; VA; WI Other Answer based on other modifiers Detail TBD Plant records of the in-line blending. RA dosage verified on asphalt supplier’s delivery documentation, bill of lading.

Agency Survey Responses (DOTs) 99   Question 46: What, if any, premature distresses have you observed for asphalt mixtures with RAs? Select all that apply: Bleeding NE Fatigue cracking Increased moisture susceptibility KS; NE Raveling NJ Reflective cracking Roughness Rutting and/or shoving Thermal cracking MO; NJ Others No premature distresses or failures have been observed to date DE; LA; MN; OH; OK; OR; PA; TN; TX; VA; WA Mixture performance testing on laboratory conditioned mixtures (long-term aging) DE; LA; MN Testing of field core MN Monitoring of field performance DE; KS; LA; MN; TN Other VA (depending upon research scope) Question 44: Does your agency evaluate the performance of asphalt binders and/or mixtures with RAs? Yes No Unsure DE; KS; LA; MN; MO; NJ; OK; TN; VA; WA AR; NE; OR; PA; TX; WI OH Question 45: How is the performance of mixtures with RAs evaluated? Select all that apply: Binder testing using standard Superpave tests LA; MO; MN; NJ; OK Binder testing using additional aging/conditioning (e.g., 40-hr PAV, EBBR) MN Mixture performance testing on STA (or plant-produced) mixtures DE; LA; NJ; TN; WA; MN

100 Use of Recycling Agents in Asphalt Concrete Mixtures Question 49: What type(s) of RA products has your agency used in these applications? Select all that apply under either/both classification systems (source/chemical composition and ASTM D4552 classification): RA0 RA1 RA5 RA25 RA75 RA250 RA500 OR OR OR NY; PA; OR OR OR OR Paraffinic Oils Aromatic Extracts Naphthenic Oils Triglycerides & Fatty Acids Tall Oils Others Unknown OR OR CA; FL; TN ID; MS; MT Other Cationic emulsified recycling agent Reclamite BioRestore Unknown Efog – Ergon product RegenX – Blackledge emulsion product Delta Mist – Collaborative Aggregates product ARA emulsions Block 3: The questions in this section are designed to gather information on the use of RAs for other applications, including the cold mix asphalt, seal coats and in-place recycled mixtures. Question 47: Does your agency currently use RAs for other applications (other than HMA, WMA and SMA)? Yes No CA; FL; ID; MS; MT; NY; OR; PA; TN AL; AK; AZ; AR; CO; CT; DE; HI; IL; IN; IA; KS; LA; ME; MD; MA; MI; MN; MO; NE; NV; NH; NJ; NM; NC; ND; OH; OK; RI; SC; TX; UT; VT; VA; WA; WI; WY Question 48: For what other applications has your agency used RAs? Select all that apply: Cold mix asphalt Seal coats Hot-in-place recycling Cold-in- place recycling Spray-on rejuvenation application Other TN FL; ID; MT; NY; OR; PA; TN CA; ID; NY; OR FL; MS; NY; OR; TN MT (scrub seal)

Agency Survey Responses (DOTs) 101   Lack of tests and criteria to approve RA AL; CA; HI; ID; IL; IN; IA; KS; ME; MD; MA; MI; MN; MS; MT; NE; NH; NJ; NC; ND; OH; OR; PA; SC; TN; UT; VT; VA; WA; WI Lack of tests and criteria to determine dosage rate and/or performance AL; HI; ID; IL; IN; IA; KS; ME; MD; MA; MI; MN; MT; NE; NH; NY; NC; OH; OR; PA; SC; TN; UT; VT; WA; WI Poor pavement performance associated with distresses and/or failures NV; UT; VT Others CO; CT; FL; ID; IN; IA; KS; MN; NH; OH; PA; SC; TN; UT; VA; WY No significant roadblocks AZ; DE; LA; MO; OK; RI; TX Other Lack of interest from our industry partners Lack of long term performance data to demonstrate effectiveness Lack of criteria to determine the effectiveness of RAs with respect to long term performance Lack of ideas/thoughts to initiate the use of RAs Lack of long-term life-cycle cost analysis of mixtures with RAs. The time it takes to perform additional testing when RAs are used Need specs in place to show how to determine dosage Lack of consistency in RAM in general Block 4: The questions in this section are designed to gather information on gaps in knowledge identified by your agency and future plans with respect to use of RAs. Question 50: Have you observed any gaps in knowledge or roadblocks that have made it challenging for your agency to start (or continue) successfully using RAs in asphalt mixtures with RAM? Select all that apply: Agency Cost of RAs relative to expected performance AK; ME; NE; NJ; NJ; NY; NC; PA; TN; VA Lack of agency experience in evaluating of asphalt mixtures with RAs AL; AK; AR; CA; HI; ID; IL; IN; IA; KS; ME; MA; MI; MN; MS; MT; NE; NV; NH; NJ; NM; NC; ND; OH; OR; PA; SC; TN; VT; VA Agency inspection process IN; MD; MA; MT; SC; TN; UT Lack of contractors’ expertise in using RAs AK; CA; HI; ID; IN; ME; MD; MA; MN; MT; NE; NJ; NY; NC; ND; OH; OR; PA; TN Lack of mix design methods and engineering- based design procedures CA; HI; IN; IA; KS; MD; MA; MI; MN; MT; NE; NY; NC; OH; PA; TN; WI; WY Lack of RA availability HI; NM; WY

102 Use of Recycling Agents in Asphalt Concrete Mixtures MT We are incorporating more recycling projects so we’ll be forced to adapt. RAM usage is still below the national average but as it increases, rejuvenators will have to play a part. NE Our primary focus over the past 4 years has been in research and laboratory testing for the use of RAs; we believe that in just a few years we will be using quite a bit of them in our mixes since we are utilizing high-end recycling quantities. NJ RAs will be used on future projects that use high RAP. NY Continued use in hot recycling; possible to see RAs evaluated in conjunction with high-RAP and PEM [performance-engineered mixture] mixes NC Real answer = yes & no Our contractors seem to be happy with our current specification, which does allow for relatively high RAM percentages without required use of RAs. However, some contractors have gone so far as to discuss performance capabilities and costs with RA suppliers, but none have designed recycled mixes using RAs. Until our industry partners approach us about using RAs in their mixes, North Carolina DOT has no immediate plans (beyond research) to use, or require the use of, recycling agents. OH Yes, we plan to use 9-58 info to help better our pavements. OK BMD, NCAT track surface. PA Ongoing research to develop methodologies and requirements for qualifying RAs, determining dosage rate via a mix design procedure, and verifying dosage rates and/or performance in production. After research completed, likely do pilot projects with the research-developed procedures. Research is scheduled to be completed by 9/30/2022. TN We have a growing program utilizing HIR and scrub seals and will continue to explore the use of RA in HMA mix design especially as an allowable tool inside a BMD process that we are in the process of developing. VA When we develop a way to accept and confirm their performance WY If we can get fresh cuttings from factory only Question 51: Does your agency have plans to use RAs in future projects? Yes No Unsure AL; AR; CA; DE; IL; LA; MD; MN; MO; MT; NE; NJ; NY; NC; OH; OK; PA; TN; VA; WA; WY CO; FL; NV; NH; NM; SC; UT AK; AZ; CT; GA; HI; ID; IN; IA; KS; ME; MA; MI; MS; ND; OR; RI; TX; VT; WI AL Planning to have a research project with the university to answer questions before formal adoption and use of RAs AR RAs are allowed by specification but the use is very limited due to the low percentage of RAM utilized by contractors. CA New NSSPs [non-standard special provisions] have been developed to examine the use of RAs in high- RAP mixes (up to 40%) and RAS mixes. DE Future specifications requiring RAs when using RAs and high percentages of RAP IL We plan to allow terminal-blended modifiers after research is completed, and are tentatively planning to implement a new binder protocol in 2022. LA Open to considering MD So far we have not needed to use RAs because we always use blending charts from AASHTO M 323 if ABR [asphalt binder ratio] is more than 30%. It is been working well for us. We will look into RAs if we have to use more RAP than what we are using now. MN Research and NRRA [National Road Research Alliance] likely to have projects in the near future MO Contractors allowed to use them in HMA mixes currently

Agency Survey Responses (DOTs) 103   NC Screening of Asphalt Extenders and Recycling Agents [NCDOT Research Project Number: 2020-16] Cassie A. Castorena – NC State University An in-depth study is needed to identify aging and test methods to better quantify binder cracking resistance to inform the development of an improved binder specification framework; this framework would enable improved, unified procedures to qualify recycling agent and extender products and establish dosage requirements. The study should rely on the use of relatively simple experiments that make use of standard binder laboratory equipment to ensure that the research results can be easily implemented. To address this need, the proposed research will achieve two objectives: (1) identify an appropriate aging procedure to simulate long-term oxidative aging coupled with a test method to characterize the cracking resistance of asphalt binders that uses Superpave binder equipment; (2) develop proposed improvements to binder specifications with corresponding recommendations for extender and recycling agent product approval and dosage selection. https://connect.ncdot.gov/projects/research/Pages/ProjDetails.aspx?ProjectID=2020-16 PA Research is currently ongoing, and no documents are publicly available. Research is to develop qualification procedure for approving RAs and then developing mix design procedures for including RAs in plant-produced asphalt mixtures containing RAM. TN Our last NCAT track section was a split demo between two surface rejuvenators. NCAT duplicated the experiment with Mississippi DOT and was thus able to do four sections. Raquel Moraes is the PI. We are additionally a lead state in the NTPEP WMA (soon to be asphalt additives based on scope creep) program that is trying to develop a clearinghouse for rejuvenators. VA RAs effects on performance and acceptance method WI Through our participation in NRRA. A project in the future may be with our WHRP (Wisconsin Highway Research Program) Question 52: Is your agency currently sponsoring (or planning to sponsor) any research related to use of RAs in asphalt mixtures with RAM? Yes No AL; CA; DE; ID; IL; IA; MN; MS; NE; NC; OK; PA; TN; VA; WI AK; AZ; AR; CO; CT; FL; GA; HI; IN; KS; LA; ME; MD; MA; MI; MO; MT; NV; NH; NJ; NM; NY; ND; OH; OR; RI; SC; UT; VT; WA; WY AL Planning to sponsor in the near future CA These are the same NSSPs updated earlier. DE Participating in NCHRP Project 20-44(24) IL Ongoing research at the Illinois Center for Transportation titled “Rheology-Chemical Based Procedure to Evaluate Additives/Modifiers used in Asphalt Binders for Performance Enhancements (Phase 2);” slides from recent presentation: https://ws.engr.illinois.edu/sitemanager/getfile.asp?id=2208 MN All the experience discussed in the survey is from MN (TH) 6 [Minnesota Trunk Highway 6]. MS We have funded some research work at NCAT to develop methods to approve RAs. We have sprayed some rejuvenator products on test sections in our highway system for future observation of performance. NE We have current research with the University of Nevada–Las Vegas (UNL), Nebraska DOT, the Nebraska Corn Board, and the Nebraska Soy Bean Board.

104 Use of Recycling Agents in Asphalt Concrete Mixtures Question 53: The synthesis will also include case examples illustrating agency practices on use of RAs. The development of the case example(s) may require an additional follow-up interview. Agencies will be provided the opportunity to review the case example write-up for accuracy. Would your agency be willing to participate as a case example? Yes No AZ; CO; DE; ID; IA; MD; MI; MN; NE; NJ; ND; OH; OK; RI; TN; VT; VA; WA AL; AK; AR; CA; CT; FL; HI; IL; IN; KS; LA; ME; MA; MS; MO; MT; NV; NH; NM; NY; NC; OR; PA; TX; UT; WI; WY Question 55: If you have any additional information or thoughts you would like to share regarding this topic, please do so here: FL I think this is a worthwhile synthesis. I am interested in any long-term performance data demonstrating RA effectiveness and effective criteria for discerning which RAs are truly beneficial and which are not. Good luck with the project. GA We have decided to use more neat asphalt concrete (AC) in our RAP mixes in lieu of RAs by limiting the amount of binder credit given to recycled binder to 60% of its binder content. ID We are interested in the survey findings. LA I wish I could be of more assistance. but RAs have only been utilized in laboratory research studies at this point (to my knowledge). MA Although we currently do not use RAs and are not looking into their use, we do believe that we will be using RAs in the future at some point. We are also curious about the evaluation of products that can be classified as binder modifiers and RAs. MN All the experience discussed in the survey is from a current project. NE We look forward and are excited about the use of RAs and recycled materials NJ Questions pertaining to RAM content based on RBR were not answered because we do not use RBR in the specifications. I tried to remove my answer to my question 4, but it would not allow me to. OH We are in the process of getting things together to use RA. VT We would be interested in a set of extended aging tests to ensure adequate lifetime performance that could be used to approve the use of RAs VA Again, we don’t have any APL for the recycling agents. We only have used for research and pilot projects. WY RAS should only incorporate fresh cuttings from factories as existing shingles are so aged that binder technology cannot correct with current PG types through grade bumps.