Short-Term Laboratory Conditioning of Asphalt Mixtures (2015)

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A-1 Construction Reports Texas Farm-to-Market Highway 973 (TX I FM 973) . . . . A-1 New Mexico Interstate Highway 25 (NM IH 25) . . . . . . . A-8 Connecticut Interstate Highway 84 (CT IH 84) . . . . . . . A-13 Wyoming State Route 196 (WY SR 196) . . . . . . . . . . . . A-17 South Dakota Highway 262 (SD SH 262) . . . . . . . . . . . . A-19 Central Iowa Expo Center (IA Fairgrounds) . . . . . . . . . A-23 Florida I-95 Rest Area (FL Parking) . . . . . . . . . . . . . . . . A-29 City of Indianapolis, Residential Streets (IN Residential) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-35 Midland-Odessa City Street (TX II Local) . . . . . . . . . . . A-41 Table A-1 provides a summary of the field sites used in this project . Besides climate (wet–freeze, dry–freeze, wet–no freeze, and dry–no freeze), the following factors were considered when selecting field sites that included a wide spectrum of materials and production parameters: • Aggregate type (high AC and low AC) • Asphalt source (fast aging and slow aging) • Recycled materials (RAP and RAS) • WMA technology (WMA and HMA) • Plant type (batch plant and drum plant) • Production temperature (high and low) Texas Farm-to-Market Highway 973 (TX I FM 973) General Description The Texas Department of Transportation (TxDOT) set up an experimental overlay on FM 973 in Travis County, in the Austin District, in order to conduct testing and long-term per- formance monitoring for several research projects . This exper- imental construction project (Project ID STP 1102 [371]) was planned to explore the different aspects of WMA, as well as the effect of RAP and RAS on the performance of HMA and WMA mixtures . Researchers involved in various state and federal studies actively participated in testing and monitoring these test sections . The overlay construction started on December 1, 2011, and took 1 .5 months to complete due to inclement weather and holidays . J . D . Ramming Paving Company was the general contractor for this project . The project site was located just north of the Austin Berg- strom International Airport (see Figure A-1) . The length of the project was approximately 2 .9 mi . Within the project lim- its, there was an aggregate quarry and a concrete plant that generated very high-volume truck traffic . Nine test sections were laid out as shown in Figure A-2 . This portion of FM 973 experiences moderate- to high- volume traffic; 2011 traffic data reported 11,000 and 11,300 annual average daily traffic for the north and south ends, respectively . Truck traffic was reported to be from 4 .2 to 4 .3 percent . Mixtures and Materials A TxDOT Type C (0 .5-in . [12 .5-mm] NMAS) surface mix- ture was used in the project . The aggregate structure was the same for all mixtures used in the various test sections . Figure A-3 presents the mix design used in Section 1 . The differences between test sections are listed in Table A-2, namely the type of mixture (i .e ., HMA vs . WMA), the type of asphalt binder (i .e ., PG 70-22, PG 64-22, and PG 58-28), and the amount of RAP/RAS added to the mixture (i .e ., 0/15/30 percent RAP and 0/3/5 percent RAS) . Binder contents of the mixtures were verified during quality control through ignition oven analysis . The asphalt binders classified as PG 70-22 (SBS-modified binder) and PG 58-28 were supplied by Binder V Asphalt Company from its Corpus Christi, Texas, refinery . Pelican Refining Company supplied the PG 64-22 (unmodified) asphalt binder from its Channelview, Texas, facility . All mixtures used virgin limestone from Cemex Aggre- gate located just across from the asphalt mixture plant . RAP and RAS came from various sources . A P P E N D I X A

Location & Climate Date Plant Type TProduction Asphalt Aggregate & Additives Mixtures Factors Texas I FM 973 Wet–No Freeze 1/12 CFD 325°F (163°C) HMA 325°F (163°C) HMA + RAP/RAS 275°F (135°C) Foaming 275°F (135°C) Evotherm® 270°F (132°C) Evotherm + RAP/RAS 5.2% PG 70-22 (Styrene- Butadiene- Styrene [SBS]) PG 64-22 w/ 15%RAP/ 3%RAS Limestone HMA HMA + 15%RAP + 3%RAS WMA Foaming WMA Evotherm DAT WMA Evotherm + 15%RAP + 3%RAS HMA vs. WMA RAP/RAS vs. No RAP New Mexico IH 25 Dry–No Freeze 10/12 CFD 345°F (174°C) HMA 315°F (157°C) HMA + RAP 285°F (141°C) Foaming 275°F (135°C) Evotherm 5.4% PG 76-28 (SBS) PG 64-28 w/35%RAP Siliceous Gravel 1% Versabind HMA HMA + 35%RAP WMA Foaming + 35%RAP WMA Evotherm 3G + 35%RAP HMA vs. WMA RAP vs. No RAP Connecticut IH 84 Wet–Freeze 8/12 CFD 322°F (161°C) HMA 312°F (156°C) Foaming 5.0% PG 76-22 (SBS) w/20%RAP Basalt HMA + 20%RAP WMA Foaming + 20%RAP HMA vs. WMA Wyoming SR 196 Dry–Freeze 8/12 CFD 315°F (157°C) HMA 255 & 275°F (124 & 135°C) Evotherm 275 & 295°F (135 & 146°C) Foaming 5.0% PG 64-28 (polymer) Limestone1% Lime HMA WMA Foaming WMA Evotherm 3G HMA vs. WMA Production Temperature (WMA) South Dakota SH 262 Dry–Freeze 10/12 CFD 310°F (154°C) HMA 275°F (135°C) Foaming 270°F (132°C) Evotherm 280°F (138°C) Advera® 5.3% PG 58-34 (SBS) w/20%RAP Quartzite 1% Lime HMA + 20%RAP WMA Foaming + 20%RAP WMA Evotherm 3G + 20%RAP WMA Advera + 20%RAP HMA vs. WMA Iowa Fairgrounds Wet–Freeze 6/13 CFD 295 & 325°F (146 & 163°C) Low Abs HMA 295 & 310°F (146 & 154°C) High Abs HMA 265 & 295°F (129 & 146°C) Low Abs Foaming 260 & 290°F (127 & 143°C) High Abs Foaming 5.0% (0.9%AC Limestone) and 7.0% (3.2% AC Limestone) PG 58-28 w/ 20%RAP 0.9%AC Limestone + Field Sand 3.2%AC Limestone + Field Sand Low Abs HMA + 20%RAP High Abs HMA + 20%RAP Low Abs WMA Foaming + 20%RAP High Abs WMA Foaming + 20%RAP HMA vs. WMA Production Temperature Aggregate Absorption Florida Parking Wet–No Freeze 8/13 CFD 306°F (152°C) Low Abs HMA 308°F (153°C) High Abs HMA 272°F (133°C) Low Abs Foaming 267°F (131°C) High Abs Foaming 5.1% (0.6%AC Granite) and 6.8% (3.7%AC Limestone) PG 58-28 w/ 25%RAP 0.6%AC Granite 3.7%AC Limestone 0.5% Liquid Anti-strip Low Abs HMA + 25%RAP High Abs HMA + 25%RAP Low Abs WMA Foaming + 25%RAP High Abs WMA Foaming + 25%RAP HMA vs. WMA Aggregate Absorption Indiana Residential Wet–Freeze 8/13 CFD BMP 300°F (149°C) HMA + RAP (CFD) 305°F (152°C) HMA + RAP (BMP) 271°F (133°C) Foaming + RAP (CFD) 273°F (134°C) Advera + RAP (BMP) 5.8% PG 64-22 Limestone HMA + 25%RAP (CFD) HMA + 25%RAP (BMP) WMA Foaming + 25%RAP (CFD) WMA Advera + 25%RAP (BMP) HMA vs. WMA Plant Type Texas II Local Dry–No Freeze 4/14 CFD BMP 310°F (154°C) HMA (Binder V, CFD) 315°F (157°C) HMA (Binder V, BMP) 310°F (154°C) HMA (Binder A, CFD) 315°F (157°C) HMA (Binder A, BMP) 6.2% PG 64-22 Limestone HMA (Binder V, CFD) @ 5.9%AC HMA (Binder V, BMP) @ 6.4%AC HMA (Binder A, CFD) @ 5.9%AC HMA (Binder A, BMP) @ 6.4%AC Plant Type Asphalt Source Table A-1. Summary of field sites.

A-3 Figure A-1. Project limits for the Texas field site. Figure A-2. Schematic layout diagram of the Texas field site test sections (not to scale).

Figure A-3. Mixture design used in Test Section 1 (HMA without RAP or RAS, PG 70-22).

A-5 Plant and Mixture Production The Ramming Paving Company’s RTI division (referred to as RTI) hot mix plant located in Buda, Texas, supplied the asphalt mixture . This plant was approximately 30 mi away from the jobsite . The driving time between the asphalt plant and job site was between 30 to 40 minutes . RTI had an approximately 10-year-old Astec double-barrel unitized drum mixer (counter- flow) with a capacity of 350 tons/hour production rate (see Fig- ure A-4) . The dimension of the drum was 35 ft in length and 8 ft in diameter . The plant also had seven cold-feed bins in addi- tion to one RAP bin and one RAS bin . There were three storage silos, with each having a capacity of 200 tons . The plant had a conventional baghouse fines collection system, and part of the baghouse fines was reintroduced into the drum . A drag slat con- veyor carried the mixture from the drum to the storage silo . The plant was equipped with one lime silo and two vertical Heatec binder storage tanks . An Astec green foaming system was added to the plant approximately 2 years prior to this construction job . The Evotherm® DAT™ WMA additive was pumped from tem- porary tanks and added to the asphalt line during production . Typically, the plant was initially operated at higher-than- normal production temperatures and was brought down to the target temperature after a few truckloads . The mois- ture content of the aggregate was somewhere between 4 and 5 percent . The average silo storage time was between 10 and 12 minutes . RTI employed 12 belly dump trucks to haul the loose mixtures to the construction site . The trucks had tarps on them to reduce heat loss . Construction The contractor repaired and patched some areas of existing surface distress (especially at the north end of the project) in November before the start of the overlay construction . Two mix- tures (i .e ., Test Section 1—HMA control, and Test Section 7— WMA foaming) were produced and placed on the first day of production on December 1, 2011 . The rest of the mixtures were produced and placed one per day . Section 1 and 7, both approximately 2000 ft long, were placed side by side on the southbound and northbound lanes, respectively . All other test sections were placed on both directions of the roadway . Just before placing the overlay, a layer of underseal (or seal coat) was placed on top of the existing pavement surface (see Figure A-5) . The seal coat used was a CHFRS-2P emulsion sprayed at a rate of 0 .25 gal/yd2 and covered by a Grade 4 Type B uncoated limestone aggregate at a rate of 260 yd2/yd3 . Then, the belly dump trucks released the loose mix on the fresh seal coat and a material transfer vehicle, alternately known as a shuttle buggy, picked up the mixture and transferred it to Section No. Lot No. Mixture Description Date of Paving Type Binder RAP % RAS % 1 1 HMA PG 70-22 0 0 12/01/11 7 2 WMA Foaming PG 70-22 0 0 12/01/11 9 3 WMA Evotherm DAT™ PG 64-22 15 3 12/13/11 8 4 WMA Evotherm DAT™ PG 70-22 0 0 01/04/12 3 5 HMA PG 64-22 15 3 01/05/12 4 6 HMA PG 64-22 0 5 01/06/12 2 7 HMA PG 64-22 30 0 01/16/12 5 8 HMA PG 58-28 30 0 01/17/12 6 9 HMA PG 58-28 15 3 01/18/12 Table A-2. List of test sections with construction date for the Texas I field site. Figure A-4. RTI hot mix plant located in Buda, Texas. Figure A-5. Application of underseal before overlay laydown.

A-6 the paver hoper (see Figure A-6) . Typically, each day the chip seal placement started at 9:00 a .m . and the paving was com- pleted by 3:30 p .m . Table A-3 shows the list of the equipment used during construction . The paver was equipped with a MOBA brand PAVE-IR bar to record the surface temperature of the mat right behind the paver (see Figure A-7) . The loose mat was compacted with one dual-wheel steel roller as a breakdown roller, one pneumatic-tire roller as an intermediate roller, and one small steel-wheel roller as a finisher . On one occa- sion, two pneumatic rollers were used . Paving was done from north to south regardless of the direction of travel . In general, the paving width was 16 ft (4 .9 m) in each direction with an average of 2 in . (50 mm) of compacted mat thickness . Sample Collection Plant mix was collected from the truck right after discharge from the silo (see Figure A-8) . Large quantities of mixtures were collected for later use in the laboratory as well as for on- site specimen preparation . In addition, the research team col- lected samples of the three asphalt binder performance grades, virgin aggregates, RAP, and RAS materials . The materials sam- pling scheme is summarized in Table A-4 . On-Site PMLC Specimen Compaction The plant loose mix collected from the truck at the plant was quickly brought to the on-site mobile laboratory and placed in the oven from 1 to 2 hours to achieve the required compaction temperature . This on-site laboratory was owned by RTI . All on- site specimens were compacted using a Troxler Superpave gyra- tory compactor to 7 ± 1 percent AV content (see Figure A-9) . As part of NCHRP 9-49, approximately thirteen 6 .0-in . (152-mm) diameter specimens were compacted on-site using plant loose mix from five test sections . Field Specimens Because of several interruptions during construction due to weather conditions and holidays, all road cores were collected after the completion of the entire project and labeled as having the same field age, although the control section (HMA with PG 70-22) was constructed during the first week of December 2011 and the final test section was paved on January 18, 2012 . The first set of road cores was collected during the last week of January 2012 . Thus, the first sets of cores collected from the different test sections were subjected to environmental and traffic conditions in the field between 2 weeks and 8 weeks . Figure A-6. Windrow operation using shuttle buggy. Equipment Type Manufacturer Model Material Transfer Vehicle Roadtec SB 25000 Paver Barber-Green BG 2000 Breakdown Roller (steel-wheeled) Volvo Pneumatic Roller Bomag 24RH Finish Roller (steel-wheeled) Ingersoll Rand Finish Roller Dynapac CC 142 Table A-3. Paving equipment used at the Texas I field site. Figure A-7. Paver equipped with PAVE-IR bar.

A-7 Figure A-8. Loose mix collection from the truck at RTI hot mix plant. Sample Type Material Point of Sampling Lab Mixed, Lab Compacted Fine Aggregate Stockpile Coarse Aggregate Stockpile RAP Stockpile RAS Stockpile Binder (all grades) Transport Truck at Asphalt Mix Plant Evotherm DAT™ Additive Asphalt Mix Plant Plant Mixed, Lab Compacted Loose Mix Truck at Asphalt Mix Plant Plant Mixed, Field Compacted First Set after Construction—January 2012 Road Cores Travel Lane (between wheelpath) Plant Mixed, Field Compacted Second Set—September 2012 Road Cores Travel Lane (between wheelpath) Plant Mixed, Field Compacted Third Set—March 2013 Road Cores Travel Lane (between wheelpath) Table A-4. Materials sampling scheme at the Texas I field site. Figure A-9. Troxler compactor used to prepare the on-site PMLC specimens.

A-8 The road cores were drilled at the center of the travel lane (between wheelpath), spread approximately equal distance on both directions . Figure A-10 shows a typical core obtained from Section 9 . The next round of road cores was obtained during the sec- ond week of September 2012—approximately 8 to 9 months after overlay construction . In addition, the research team also collected a third set of cores from the test sections during March 2013 . Field Performance An overall assessment of the condition of the pavement was performed on three occasions: 2 to 3 months, 6 to 7 months, and 14 to 15 months after construction . The conditions of Sections 1, 7, and 8 are shown in Figures A-11, A-12, and A-13 . New Mexico Interstate Highway 25 (NM IH 25) General Description The New Mexico test sections were located on IH 25 between Williamsburg and Elephant Butte, Sierra County, in the south- east part of the state . An overall view of the construction site is shown in Figure A-14 . IH 25 is a four-lane (two lanes in each direction) rural highway with moderate traffic . The stretch of highway where the test sections were placed is characterized by rolling terrain . This field site was constructed during the third week of October 2012 . James Hamilton Construction Com- pany from Silver City, New Mexico, was the contractor for this project . The total length of the overlay project was approximately 18 mi (28 .8 km) . Near the location of the test sections, the total roadway width was 26 ft . The main-lane paving width was approximately 13 ft . The average overlay thickness was 2 .5 in . (63 mm) . The existing pavement surface had moderate to severe alligator cracking on the wheelpath . Therefore, before Figure A-10. Typical Texas pavement structure including the recent overlay. (a) HMA (b) WMA Foaming (c) WMA Evotherm Figure A-11. Performance of the Texas field sections after 2 to 3 months in service.

A-9 (a) HMA (b) WMA Foaming (c) WMA Evotherm Figure A-12. Performance of the Texas field sections after 6 to 7 months in service. (a) HMA (b) WMA Foaming (c) WMA Evotherm Figure A-13. Performance of the Texas field sections after 14 to 15 months in service.

A-10 placing the overlay, the top of the existing pavement was milled off 2 .5 in . (63 mm) . Mixtures and Materials The New Mexico Department of Transportation (NMDOT) used a 0 .75-in . (19-mm) NMAS dense-graded mixture (i .e ., NMDOT SPIII) for the surface layer . The aggregate, a siliceous rock, was obtained from a nearby pit located very close to the Rio Grande River . This type of aggregate is highly absorptive; the combined aggregate water absorption at saturated surface dry condition was reported as 2 .9 percent . The moisture con- tent of the aggregate was between 3 .5 to 4 .0 percent . Thirty- five percent RAP was also added to the mixture, which was screened over a 2-in . (50-mm) sieve . Besides the control HMA with RAP mixture, this project included a control HMA without RAP, WMA Foaming with RAP, and Evotherm 3G with RAP . Only 500 tons of HMA without RAP and approximately 2000 tons of WMA with Evo- therm 3G were placed . The HMA without RAP mixture used 5 .4 percent PG 76-22 asphalt binder . The other three mixtures, which included 35 percent RAP, were designed with a PG 64-28 modified asphalt binder . The percentage of virgin binder and total binder content for these mixtures was 3 .0 percent and 5 .4 percent, respectively . NuStar Energy Company from Santa Fe, New Mexico, supplied both asphalt binder types . Evotherm 3G was blended with the asphalt binder at 0 .5 percent by weight of total binder content at the asphalt mixture plant . The plant was equipped with an Astec Green System asphalt foaming system . During mixture production, the water added to produce the WMA foaming mixture was reported as 2 .0 percent by weight of virgin asphalt binder content . Except for the HMA with RAP mixture, all other mixtures used the same aggregate gradation and binder content . Binder con- tents of the mixtures were verified during quality control through ignition oven analysis . All four mixtures incorpo- rated 1 percent Versabind mineral filler mixed with the virgin aggregates at 4 .4 percent moisture content using a pug mill before entering into the drum through the conveyor belt . The moisture content of the aggregate was approximately 3 .5 to 4 .0 percent . All four Superpave mixtures were designed at 100 gyrations (Ndes) . The mix designs with and without RAP are detailed in Figures A-15 and A-16 . Plant and Mixture Production The asphalt mixture plant, a portable Astec double barrel (see Figure A-17), was a counter-flow drum design with an external mixing drum . The plant was about 10 years old at the time of construction . The capacity of the plant was 450 tons/ hour, and it had two horizontal binder tanks . The plant did not have a silo; rather, it had a 50-ton capacity Astec surge bin . The plant used three (out of five) cold bins for virgin aggregates . RAP materials were screened over a 2-in . (50-mm) screen before entering the mixing drum . The plant had a conventional baghouse fines collection system, and part of the baghouse fines was reintroduced into the drum . A drag slat conveyor carried the mixture from the drum to the surge bin . Typically, the plant operator started production at a higher temperature and then lowered it to the target mixing tem- perature after four or five truck loads . In this project, the majority of the asphalt mixture that was produced consisted of WMA foaming with 35 percent RAP . Although the proj- ect was almost 18 mi (29 .0 km) long, the test sections were located within 3 mi (4 .8 km) . Table A-5 shows the tempera- ture data for the particular production day and time when the loose mix for each mixture type was collected . Construction The asphalt mixture plant was located at the north end of the project, while the test sections were located toward the south end . The average hauling distance and time from the plant to the test sections were approximately 15 mi and 20 minutes, respectively . The mixtures were hauled using belly dump trucks with a tarp on top . Once the belly dump trucks released the mixtures on the road, a windrow pick- up machine (see Figure A-18) transferred the mixtures and dropped them into the paver chute . This job used three steel-wheeled rollers (see list of paving equipment in Table A-6) . The breakdown roller was used to compact the loose mix using seven passes in vibratory mode . The intermediate roller immediately followed, compacting with approximately seven passes . Surprisingly, the finish roller also operated in vibratory mode, although at very low frequency and low amplitude . The finish roller also used seven passes . Before paving, the contractor applied CSS-1H tack coat with a mixture ratio of 2:1 at a rate of 0 .05 gal/yd2 (0 .23 L/m2) over the milled surface . Figure A-14. New Mexico IH 25 field site.

A-11 Figure A-15. Mix design for HMA and WMA mixtures with 35 percent RAP.

A-12 Figure A-16. Mix design for HMA mixture without RAP.

A-13 Figure A-17. Asphalt mixture plant at the New Mexico field site. Figure A-18. Windrow equipment used at the New Mexico field site. Mixture Type Date of Production Plant Mix Temp (F) Paving Temp (F) Ambient Temp (F) WMA Foaming with RAP 10.16.12 285 265–270 60 to 80 HMA with RAP 10.17.12 315 285–290 60 to 80 HMA without RAP 10.18.12 345 330–335 60 to 80 WMA Evotherm 3G with RAP 10.19.12 275 255–260 60 to 80 Table A-5. Production, paving, and ambient temperatures for the New Mexico field site. Equipment Type Manufacturer Model Windrow Weiler E 650A Paver Caterpillar Inc. CAT 10-20B Breakdown Roller (steel-wheeled) Bomag HYPAC C784A Intermediate Roller (steel-wheeled) Bomag HYPAC C784A Finish Roller (steel-wheeled) Bomag HYPAC C784A Table A-6. Paving equipment used at the New Mexico field site. Sample Collection Plant mix was collected right after the trucks released the mixtures in front of the windrow (see Figure A-19) . The time that elapsed between the truck leaving the plant and the loose mix sample collection was approximately 20 min- utes . A large quantity of mixtures was collected for later use in the laboratory using the scheme listed in Table A-7 . A smaller quantity of mixture collected from the road was immediately brought back to the FHWA mobile laboratory trailer located next to the project site for on-site specimen compaction . The research team also collected PG 76-22 and PG 64-28 asphalt binder, virgin aggregate, Versabind (mineral filler), Evotherm 3G, and RAP from the asphalt mixture plant . With the help of the contractor’s personnel, 48 road cores from four test sections were collected right after construction . On-Site PMLC Specimen Compaction Fifty-six 6-in . (150-mm) diameter specimens were com- pacted on-site using plant mix at the FHWA mobile laboratory trailer located next to the project site in Williamsburg . Thirty- two of them were 2 .4 in . (61 mm) tall, and 24 of them were 3 .75 in . (95 mm) tall . Plant loose mix collected by the wind- row was quickly brought to the mobile laboratory trailer and placed in the oven for from 1 to 2 hours to achieve the desired compaction temperature . Specimens were compacted using an IPC Superpave gyratory compactor to 7 ± 1 percent AV content . In addition, six specimens of each of these four mix- tures were compacted for Asphalt Mixture Performance Tester (AMPT) testing . The AMPT specimens were cored and sawed from larger specimens to a final dimension of 4 in . (100 mm) in diameter by 6 in . (150 mm) in height . Connecticut Interstate Highway 84 (CT IH 84) General Description This overlay project located on westbound IH 84 (Fig- ure A-20) on the eastside of Hartford Connecticut, was con- structed in the third week of August 2012 . Tilcon, Inc ., of

A-14 Oldcastle Materials Group, was the contractor for this overlay paving job . This stretch of IH 84 is a heavily trafficked road located in urban area . The paving job was done during the night time . The average thickness was 2 .0 in . (50 mm) . The asphalt plant was located about 24 miles from the construction site . The hauling time was approximately 30 to 45 minutes . Researchers from National Center for Asphalt Technologists (NCAT) were present during the construction for monitoring and sample collection . They also brought their mobile labora- tory into the asphalt plant for sample collection and specimen preparation . Mixtures and Materials This project used a 0 .5-in . (12 .5-mm) NMAS dense-graded Superpave mixture designed with 100 gyrations for the surface layer . A basalt virgin aggregate was used with 20 percent RAP in this mixture . The RAP came from multiple sources . RAP materials were crushed to 0 .5 in . (12 .7 mm) and then screened over a 9⁄16-in . (14 .3-mm) sieve before entering the plant . Two types of mixtures used in this job were: HMA and WMA foaming . Both mixtures were identical in design except that the WMA foaming used 2 percent water by weight of binder . The aggregate stockpile percentages are provided in Table A-8 . The total binder content of this mixture was 4 .9 percent . The virgin binder and the binder from RAP were 3 .7 percent and 1 .2 percent, respectively . Binder contents of the mixtures were verified during quality control through ignition oven analysis . The virgin binder, PG 76-22 (SBS modified), was supplied by Pekham Materials from Athens, New York . This mixture did not have any anti-stripping agent . The detail mix design is shown in Figure A-21 . Figure A-19. Loose mix sampling at the New Mexico field site. Sample Type Material Point of Sampling Lab Mixed, Lab Compacted Fine Aggregate Stockpile Coarse Aggregate Stockpile RAP Stockpile Versabind Silo PG 76-22 Asphalt Transport Truck PG 64-28 Asphalt Transport Truck Evotherm 3G Plant Plant Mixed, Lab Compacted Loose Mix Windrow Plant Mixed, Field Compacted First Coring—October 2012 Road Cores Main Lane (between wheelpath) Table A-7. Material sampling scheme at the New Mexico field site. Aggregate Stockpile Total Aggregate (%) 1/2s 29.6 Natural Sand 6.4 Stone Sand A 11.2 Stone Sand B 23.2 Crushed RAP 32.8 Table A-8. Aggregate percentages for of HMA production and WMA production at the Connecticut field site. Figure A-20. IH 84 at the Connecticut Field Site.

A-15 Figure A-21. Mix design for CT IH 84.

A-16 Plant and Mixture Production The asphalt plant was an Astec double barrel, a counter-flow drum design with an external mixing drum (Figure A-22) . The production capacity of the plant was 400 tons/hour, and it had two horizontal binder tanks . The plant had nine 300-ton silos . The plant had a conventional baghouse fines collection system, and part of the baghouse fines was reintroduced into the drum . Drag slat conveyor carried the mixture from the drum to a silo . The plant was equipped with an Astec Green System asphalt foaming system . Table A-9 shows the data for the particular production day and time when loose mix was collected . There was very little difference (10°F) between the production temperature of HMA and WMA for this job . This was a conscious decision of the agency . Construction Paving for both technologies (mixtures) were done in tan- dem with two different pavers . The average distance between the asphalt plant and the construction site was approximately 24 mi . The average haul time was approximately 30 to 45 min- utes . The mixtures were hauled using 24 belly dump trucks with tarps (12 to each paving crew) . Once the belly dump trucks released the mixtures on the road, a material transfer device picked up the mixtures and dropped them into the paver chute . This job used two steel-wheeled rollers and one pneumatic roller (Table A-10) . The paver was equipped with Pave-IR bar (Figure A-23) to measure the temperature of the mat right behind the paver . Sample Collection Aggregate and mixture moisture samples were taken twice a night . Finally, the aggregate, RAP, and virgin binder used in the mixtures were sampled so that LMLC specimens could be fabricated . Plant mix was collected from the truck at the plant . The research team also collected some road cores from these test sections . The materials sampling scheme is shown in Table A-11 . Figure A-22. Tilcon asphalt plant. Figure A-23. Paver equipped with PAVE-IR bar. Mixture Date of Production Plant Mix Temp Paving Temp HMA 08.19.12 322°F (avg.) 296°F (avg.) WMA Foaming 08.20.12 312°F (avg.) 294°F (avg.) Table A-9. Production, paving, and ambient temperatures at the Connecticut field site. Equipment Type Manufacturer Model Material Transfer Device Paver Caterpillar Inc. CAT AP1000D Breakdown Roller (Steel-wheeled) Caterpillar Inc. Pneumatic Roller Caterpillar Inc. Finish Roller (Steel-wheeled) Caterpillar Inc. Table A-10. Equipment used for placement and compaction at the Connecticut field site.

A-17 Field LMLC Specimen Compaction NCAT’s mobile laboratory was on site for both nights of paving . Twenty-five 5-gal buckets of mixture were sampled each night about 2 hours into production once the plant was running smoothly . Volumetric and performance samples were compacted on the laboratory each night without letting the mixture cool down in order to negate the effect of reheat- ing the mixture . The following samples were made: • Three volumetric samples at 100 gyrations using the same mass as the quality control laboratory • E* and flow number • S-VECD • Hamburg • IDT • Overlay tester • TSR Wyoming State Route 196 (WY SR 196) General Description The Wyoming project (Project STP 1006020) was sampled in cooperation with Western Research Institute and the Wyo- ming Department of Transportation (WYDOT) . This 1 .5-in . (38-mm) overlay project was constructed on State Route 196 (Figure A-24) near the town of Buffalo during the third week of August 2013 . McGarvin-Moberly Construction Co . was the general contractor for this project . This overlay project was approximately 5 mi long . Besides HMA, two WMA technologies were used in this project: foaming and Evotherm . Two different production temperatures were used with each technology . WYDOT per- sonnel collected all the samples and data and prepared speci- mens on site . Mixtures and Materials The mixtures consisted of a 0 .5-in . (12 .5-mm) NMAS dense- graded aggregate with 5 percent PG 64-28 binder from Cenex (polymer modified) and 1 percent lime . No RAP was used in these mixtures . Mixtures produced included a control HMA (315°F [157°C]), Evotherm warm mix at two different temper- atures (275°F [135°C] and 255°F [124°C]), and Gencor foam warm mix at two different temperatures (295°F [146°C] and 275°F [135°C]) . The mixtures contained 36 percent coarse aggregate (1⁄2 in . [12 .7 mm]), 16 percent coarse aggregate (3⁄8 in . [9 .5 mm]), 40 percent crushed fines, and 8 percent washed sand to achieve the gradations in Table A-12 . All five sections essentially had same aggregate structure and binder content . The mixtures contained 5 .0 percent PG 64-28 added by weight of total mixture and 1 .0 percent hydrated lime added by weight of dry aggregate . Plant and Mixture Production The plant was a portable, counter-flow drum manufactured by Gencor with a 70-ton silo (Figure A-25) . This Gencor Ultra Drum with a production capacity of 400 tons/hour was built in 1997 . The dimensions of the drum was 9 ft . (2 .7 m) in diameter and 46 ft . (14 m) long . The plant had two horizontal binder storage tanks . The plant was fitted with Gencor Ultrafoam GX System foaming device (Figure A-26) . Weather was generally mild to warm throughout the dura- tion of the paving . Partial to full sun was visible during paving and temperatures were between 65°F to 85°F (18°C to 29°C) . The plant production temperatures and ambient tempera- tures are presented in Table A-13 . There was little or no wind except on the morning of August 22 when there was some strong wind . Sample Type Material Point of Sampling Lab Mixed, Lab Compacted Fine Aggregate Stockpile Coarse Aggregate Stockpile RAP Stockpile PG 76-22 Binder Plant Plant Mixed, Lab Compacted Loose Mix Truck at the Plant Plant Mixed, Field Compacted Road Cores Main lane Table A-11. Sample collection scheme at the Connecticut field site. Figure A-24. Field site on WY Route 196.

A-18 Construction The average distance between the asphalt plant and the construction site was only 3 mi (4 .8 km) . The haul time was approximately 5 to 7 minutes . The mixtures were hauled using belly dump trucks with tarp . Once the belly dump trucks released the mixtures on the road in a windrow, they were picked up and dropped into the paver chute . This job used two steel-wheeled vibratory rollers for breakdown (Figure A-27) . Each of the breakdown rollers typically made five passes followed by five passes of pneumatic-tired roller (Figure A-28) . The finish roller operated at static mode made 2 to 3 passes . The equipment used in placing the mix- tures is given in Table A-14 . Due to the short haul distance and favorable weather condition, the mixture temperatures decreased only 5°F to 10°F, as presented in Table A-13 . The paving temperatures were very close the mixture produc- tion temperature . Sample Collection Loose mix was collected from the plant for on-site and off-site laboratory-compacted specimens . Besides plant- produced loose mix, bulk quantity of aggregate and asphalt were collected from the plant and later shipped to the research team for further testing . The sampling scheme is presented in Table A-15 . Samples of loose mix were taken from the silo using a front-end loader as shown in Figures A-29 and A-30 . WYDOT personnel also obtained 26 road cores from these five sections . Sieve Size WYDOT Gradation Dowl Hkm Combined Gradation Stockpile Average JMF JMF Tolerance Wide Band Specification in. 100 100 100 100 100 100 in. 93 94 94 94 90 to 100 90 to 100 in. 74 74 76 74 70 to 80 55 to 90 No. 4 44 44 44 44 39 to 49 35 to 70 No. 8 31 30 31 30 26 to 34 20 to 55 No. 30 17 15 16 15 12 to 18 5 to 35 No. 200 5.6 5.2 5.8 5.0 3.0 to 7.0 2 to 7 Table A-12. Aggregate gradation for the Wyoming field site. Mixture Date of Production Plant Mix Temp Paving Temp Ambient Temp Hot mix 08.20.2012 315°F 305°F 65°F to 85°F WMA Foam 08.20.2012 295°F 290°F WMA Foam 08.21.2012 275°F 270°F WMA Evotherm 3G 08.22.2012 275°F 270°F WMA Evotherm 3G 08.23.2012 255°F 250°F Table A-13. Plant, paving, and ambient temperatures for the Wyoming field site. Figure A-25. Asphalt plant at the Wyoming field site. Figure A-26. WMA foaming system at the Wyoming field site.

A-19 Figure A-27. Breakdown with vibratory rollers. Figure A-28. Compaction using pneumatic roller. Equipment Type Manufacturer Model Windrow Paver Caterpillar Inc. CAT AP1055D Two Breakdown Rollers (Steel-wheeled) Caterpillar Inc. CAT CB64 Pneumatic Roller Bomag Finish Roller (Steel-wheeled) Dynapac Table A-14. Equipment used for laydown and compaction at the Wyoming field site. Sample Type Material Point of Sampling Lab Mixed, Lab Compacted Fine Aggregate Stockpile Coarse Aggregate Stockpile Lime Silo PG 64-28 Asphalt Transport Truck Plant Mixed, Lab Compacted Loose Mix Silo Through a Front Loader Plant Mixed, Field Compacted Road Cores Main Lane (between wheelpath) Table A-15. Material sampling scheme at the Wyoming field site. Field PMLC Specimen Compaction Thirty 6-in . (150-mm) diameter and 2 .4-in . (61-mm) tall specimens were compacted on site using plant mix at the WYDOT laboratory located in Buffalo, WY . Plant loose mix collected from the silo using a front loader was quickly brought to the laboratory and placed in the oven between 1 and 2 hours to achieve respective compaction temperature for that partic- ular mixture . Specimens were compacted using a Superpave gyratory compactor to 7 ± 1 percent AV content . South Dakota Highway 262 (SD SH 262) General Description The South Dakota warm mix test sections, located on South Dakota State Highway 262 between Bridgewater and Alexandria (Figure A-31), were constructed during the first and second week of October 2012 . This construction project, P 0262(06)356, was mainly designed as part of a South Dakota Department of Transportation (SDDOT) WMA research proj- ect conducted by the University of Nevada, Reno . The project location was in the southeast part of the state spread between two counties: Hanson and McCook . The contractor for this job was Commercial Asphalt Company located at Spencer, SD . Commercial Asphalt Company is part of Spencer Quarries, Inc . Besides TTI, two other universities participated in this project: University of Nevada, Reno, and Louisiana State University Transportation Research Center (NCHRP 9-48) . SD 262 is a two-lane two-way rural highway with light to moderate traffic . Occasionally it experiences some high- volume farming-related truck traffic . The total length of the project was approximately 17 mi (27 .22 km) with average pav- ing width of 28 ft . (8 .54 m) . The average thickness was 2 .0 in . (50 mm) . Most of the existing pavement has old concrete pavement underneath . It had moderate to severe transverse

A-20 and longitudinal cracking . Before the placement of the overlay, the existing pavement was milled to a depth of 1 .0 in . (25 mm) . Later the milled surface was either patched or bladed as needed to make it level . Some small areas had two lifts of overlay . Mixtures and Materials This project used a 0 .5-in . (12 .5-mm) NMAS dense- graded (SDDOT Q2R) for the surface layer . This mixture used virgin aggregate (quartzite) from nearby Spencer Quar- ries . The 20 percent RAP used in this mixture also contained mostly quartzite rocks . The RAP materials were screened over a 1 .5-in . screen . Besides the control HMA mixture, this project had three WMA sections made with Plant Foaming, Advera®, and Evo- therm . Approximately 5000 tons or more of mixtures were paved using each of the WMA technologies . Jebro Inc . pro- vided the SBS-modified PG 58-34 binder, manufactured using various Canadian sources, from its Sioux City, Iowa, terminal . Advera was added with the mixture at the asphalt plant, but Evotherm (3G) was blended with the binder at the terminal . The plant was equipped with an Astec Green System asphalt foaming system . All four mixtures basically used same aggre- gate structure . All four mixtures used 1 percent hydrated lime mixed with the virgin aggregates using a pug mill before enter- ing into the drum through the conveyor belt . The moisture content of the aggregate was approximately 1 .5 to 2 percent . A recent drought in South Dakota made the aggregates fairly dry . All four Superpave mixtures were designed at 50 gyrations (Ndes) and had 3 .8 percent and 5 .3 percent virgin binder and total binder content, respectively . Binder contents of the mix- tures were verified during quality control through ignition oven analysis . Detailed mixture designs are shown in Figure A-32 . Plant and Mixture Production The asphalt plant, a portable Astec double barrel (Fig- ures A-33 and A-34), was a counter-flow drum design with an external mixing drum, and was 4 years old . The capacity of the plant was 400 tons/hour and it had two horizontal binder tanks . The plant did not have a silo; rather, it had a 50-ton capacity Astec surge bin . The plant used four (out of five) cold bins for virgin aggregates . RAP materials were screened over a 3-in . screen before entering into the mixing drum . The plant had a conventional baghouse fines collection system, and part of the baghouse fines was reintroduced into the drum . A drag slat conveyor carried the mixture from the drum to the surge bin . During the construction the slat conveyor experienced some malfunctions, especially during the production at lower temperatures (WMA) . These malfunctions were most likely due to the high power requirements for the drag slat electric motors during WMA production . Figure A-29. Mixture samples retrieved by bucket loader. Figure A-30. Plant mix samples placed in buckets. Figure A-31. SD 262 field site.

A-21 Figure A-32. HMA mix design for South Dakota SD 262.

A-22 Typically, the plant operator started the production at a higher temperature and lowered to the target mixing temperature within four to five truck loads . In this project, the majority of the asphalt mixture was supposed to be HMA . At the beginning of the project, the contractor started producing only hot mix; later they produced foam WMA . Nevertheless they produced and placed mixtures for 2 days each with Advera WMA and Evo- therm WMA mixture . Table A-16 presents the data for the par- ticular production day and time when loose mix was collected . Construction The average distance between the asphalt plant and the con- struction site was approximately 15 mi . The average hauling time was approximately 20 minutes . The mixtures were hauled using belly dump trucks with tarps . Once the belly dump trucks released the mixtures on the road, windrow picked up the mix- tures and dropped them into the paver chute . This job used two steel-wheeled rollers and one pneumatic roller The breakdown roller compacted the paved mixture using four passes in vibra- tory mode . A pneumatic-tired roller was used as an intermediate roller for approximately four passes . The finish roller operated in both vibratory and static modes . The finish roller typically used one to two vibratory passes followed by one to two static passes . Starting from the laydown by the paver to the compac- tion by finish roller, paving was completed within 20 to 25 min- utes . Before paving, the contractor applied CSS1H tack coat with a mix ratio of 2:1 @ 0 .05 gal/yd2 (0 .23 L/m2) rates . Table A-17 shows the equipment used for laydown and compaction . The paver was instrumented with Pave-IR bar provided by MOBA . The Pave-IR bar collected the temperature of the mixture just behind the paver for the entire project length . Sample Collection Plant mix was collected from the road right after the trucks released the mixtures in front of the windrow for an average of approximately 25 minutes between production and sampling . Figure A-33. Commercial Asphalt Inc. plant in South Dakota. Figure A-34. Counter-flow drum at Commercial Asphalt Inc. plant in South Dakota. Mixture Date of Production Plant Mix Temp Paving Temp Ambient Temp WMA Foaming 10.03.12 270–275°F WMA Advera 10.04.12 275–280°F 240–250°F 52°F WMA Evotherm 3G 10.05.12 265–270°F HMA 10.08.12 300–310°F 275–280°F 45°F Table A-16. Production, paving, and ambient temperatures at the South Dakota field site. Equipment Type Manufacturer Model Windrow Weiler E 650A Paver Caterpillar Inc. CAT AP1055E Breakdown Roller (Steel-wheeled) Caterpillar Inc. CAT CB64 Pneumatic Roller Caterpillar Inc. CAT PS360B Finish Roller (Steel-wheeled) Caterpillar Inc. CAT CB64 Table A-17. Paving equipment used at the South Dakota field site.

A-23 Large quantities of mixtures were collected for later use in the laboratory at TTI . The materials sampling scheme is pre- sented in Table A-18 . A smaller quantity of mixture collected from the road was immediately brought back to the SDDOT mobile laboratory located within the asphalt plant for com- paction into 150-mm by 61-mm and 150-mm by 95 .25-mm samples . The research team collected straight PG 58-34 and PG 58-34 binder blended with Evotherm, virgin aggregate, and RAP from the asphalt plant . Hydrated lime and Advera samples were provided by the respective manufacturer . With the help of SDDOT personnel, the research team also col- lected 40 road cores from four test sections . Field LMLC Specimen Compaction Fifty-six 6-in . (150-mm) diameter specimens were com- pacted on site using plant mix at the SDDOT mobile labo- ratory located within the asphalt plant premises . Thirty-two of them were 2 .4 in . (61 mm) and 24 of them were 3 .75 in . (95 .25 mm) tall . Plant loose mix collected at the windrow was quickly brought to the mobile laboratory and placed in the oven between 1 to 2 hours to achieve respective compac- tion temperature for that particular mixture . Specimens were compacted using a Pine portable Superpave gyratory com- pactor (Model AGFB) to 7 ± 1 percent AV content . Central Iowa Expo Center (IA Fairgrounds) General Description Unlike other test sections, Central Iowa Expo Center test sections, located in Boone County, were not laid out on a high- way . Instead the test sections were laid out on a county fair- ground . The fairground is located on SH 17—a few miles east of Boone, Iowa . The fairground has a number of north–south and east–west streets forming a rectangular grid . As shown in Figure A-35 north–south (vertical) streets had eight different asphalt test sections and the east–west (horizontal) streets had concrete test sections . These streets are typically subjected to light- to medium-weight seasonal traffic during the fair and other special occasions . Although the owner of this facility is Boone County, the Iowa Department of Transportation paid for and executed this construction project . The surface layer (asphalt) was constructed toward the end of June 2013 . This construction project, RTB-RB-34(013)-90-00, was mainly set up as a part of NCHRP 9-52 to study the effect of aggre- gate absorption and production temperature . Researchers from Iowa State University also conducted some of their tests at this location to study several aspects of asphalt and concrete pavements . The contractor and consultant of this job were Manatts, Inc . and Foth Infrastructure & Environ- ment, LLC, respectively . Each of the 13 streets with asphalt surface is approximately 700 ft (213 m) long and 18 ft . (5 .5 m) wide (Figure A-36) . Due to an east–west concrete pavement at the midway, each of the asphalt pavement streets was divided into two segments . The average thickness of surface layer was 2 .0 in . (50 mm) . Typically a 4-in . asphalt base mixture was placed on top of the existing 6-in . (150-mm) flexible base before paving the 2-in . (50-mm) surface layer . Some of the sections had addi- tional treated sub-base or geo-grid beneath the flexible base layer . These test sections consisted of eight different mixtures (two levels of asphalt absorption × two mixtures [HMA and WMA] × two production temperatures) . Mixtures and Materials This project used a 0 .5-in . (12 .5-mm) NMAS dense- graded mixture for the surface and base layers . Two separate mixtures were designed using two different aggregate blends: one with relatively low absorption (<1 .0 percent) and one with high-absorption aggregate (≥1 .5 percent) . Again, each of these two aggregate blends was used to design HMA and foaming WMA . The plan was for each of the four mixtures to be produced at two different temperatures (control and con- trol + 30°F) . Due to some operational problems at the plant, production temperatures were adjusted from the planned temperatures . Figures A-37 and A-38 present the details of mixture designs . Low-absorptive aggregate blends used limestone aggre- gates from Martin Marietta, Ames Mine, located just north of Ames, Iowa . Additionally, these mixtures used some field sand and 20 percent RAP . These aggregate blends had approx- imately 0 .90 percent water absorption . Sample Type Material Point of Sampling Lab Mixed, Lab Compacted Fine Aggregate Stockpile Coarse Aggregate Stockpile RAP Stockpile Lime Manufacturer’s Plant PG 58-34 Asphalt Transport Truck PG 58-34 Asphalt with Evotherm Transport Truck Plant Mixed, Lab Compacted Loose Mix Windrow Plant Mixed, Field Compacted Road Cores Main Lane (between wheelpath) Table A-18. Materials sampling scheme at the South Dakota field site.

A-24 The high-absorptive aggregate blends had limestone aggre- gate from Martin Marietta, Sully Mine, located just south of Newton, Iowa . Although both blends used field sand from the same source, the high-absorptive blends used 20 percent RAP from a different source . These aggregate blends had approxi- mately 3 .2 percent water absorption . Bituminous Materials Company provided the PG 58-28 binder from its Des Moines, Iowa, terminal . The asphalt was produced at Flint Hills Resources refinery at Rosemount, Minnesota . This refinery used crude oil from Canadian source and did not use any modifier . For any given aggregate blend (low or high absorption), all four mixtures basically used the same aggregate structure . None of the mixtures used any anti- stripping agent . The moisture content of the low-absorptive aggregates was approximately 4 .5 percent . The moisture con- tent of the high-absorptive aggregates was approximately 6 .5 percent . A heavy shower was reported a few days prior to surface layer paving . All mixtures were designed follow- ing the Superpave method at 76 gyrations (Ndes) . Mixtures with low-absorptive aggregate had 4 .1 percent and 5 .1 per- cent virgin binder and total binder content, respectively . On the other hand, mixtures with high-absorptive aggregate had 6 .0 percent and 7 .0 percent virgin binder and total binder content, respectively . However quality control data shows that slightly higher (0 .1 to 0 .25 percent) total asphalt content was found in the low-absorptive mixture . Binder contents of the mixtures were verified during quality control through ignition oven analysis . During the production of WMA, the quantity of water used was 1 .5 percent of virgin binder content . Figure A-35. Layout of test section at Central Iowa Expo Center. Figure A-36. Typical test section at Central Iowa Expo Center.

A-25 Figure A-37. Central Iowa Expo Center low-absorption HMA mix design.

A-26 Figure A-38. Central Iowa Expo Center high-absorption HMA mix design.

A-27 Plant and Mixture Production The asphalt plant, a Cedar Rapids E 400 SL (Figure A-39), was a counter-flow drum . Although the plant was erected in 1995, the old drum was replaced with this new one in 2012 . Previously, this plant was a batch plant . Due to the transfor- mation from batch plant to drum plant, the drum has unusu- ally high elevation . This natural gas–operated plant has a maximum capacity of 350 tons/hour mixture production . The dimensions of the drum were 48 ft (14 .6 m) long and 100 in . (2 .54 m) in diameter . The length of mixing zone and drying zone were 18 ft (5 .5 m) and 30 ft (9 .1 m), respectively . The plant had two Cedar Rapids silos, each with a capacity of 200 tons, and three horizontal binder tanks . The drag slat conveyor belt was heated/insulated and in good condition . The plant used six cold-feed bins, which were used for vir- gin aggregates and RAP . RAP materials were screened over a 2-in . (50-mm) screen before entering into the mixing drum . The plant had a conventional (cyclone) baghouse fines collec- tion system, and part of the baghouse fines was reintroduced into the drum . Plant modification to accommodate foaming WMA was performed in 2013 using a unit supplied by Aqua Foam (Figure A-40) . Typically, the plant operator started the production at a higher temperature and lowered to the target mixing tem- perature within four to five truck loads . Binder temperature at storage tank was always maintained between 310°F to 312°F (154°C to 155°C) . At the beginning of the project, the contractor started producing only hot mix; later it produced foaming WMA . Table A-19 presents the production sequence and temperature data for the particular production day and time when loose mix was collected . Due to some technical problems with baghouse fines collection system, the plant operator produced the high-temperature and high-absorption mixture at 10°F to 15°F higher than originally planned . Total tonnage for each of the surface mixtures varied between 300 and 500 tons . An illustration of the paving operation is presented in Figure A-41 . Construction The average distance between the asphalt plant and the construction site was approximately 15 mi (24 km) . The average hauling time was approximately 20 to 25 minutes . The mixtures were hauled using rear dump trucks with tarp on top . The rear dump trucks released the loose mix directly Figure A-39. Manatts, Inc. plant at Ames, Iowa. Figure A-40. Asphalt foaming system at Manatts, Inc. plant.

A-28 into the paver hopper . This job used one standard-sized steel- wheeled roller and a small steel-wheeled finish roller . The breakdown roller compacted the loose mix using four to six passes in vibratory and static mode . The finish roller typically used three to four passes in static mode . Starting from the laydown by the paver to the compaction by finish roller, pav- ing was completed within 15 to 20 minutes . Table A-20 shows the equipment used for laydown and compaction . Minimum mixture temperature reduction was achieved due to moder- ate ambient temperature and short hauling distance . Prior to the placing of 2-in . (50-mm) thick surface layer, all the sections were paved with a 4-in . (100-mm) thick asphalt base layer using only foaming WMA low-absorption mixture produced at the control temperature (260°F [127°C]) . The research noted the beginning and ending of each test section . Before paving, the contractor applied a CSS1H tack coat with mix ratio of 2:1 @ 0 .05 gal/yd2 (0 .23 L/m2) rates . Sample Collection Plant mix was collected from the truck at the plant . There was scaffolding at the rear end of the plant . Some of the trucks were routed next to the scaffolding for sampling after they were loaded with loose mix from the silo . Loose mix from the plant was collected for on-site specimen compaction and later use in the laboratory at TTI . The materials sampling scheme is pre- sented in Table A-21 . The research team collected straight PG 58-28, virgin aggregate, and two different RAP sources from the asphalt plant . The contractor obtained the road cores as part of the Iowa Department of Transportation’s QA plan . After density measurement by the contractor, the research team obtained the cores for further testing at TTI’s laboratory . All loose mix, binder, cores, aggregate, RAP, and in-site specimens were brought back to Texas using a freight company . Figure A-41. Paving of surface layer at Central Iowa Expo Center. Table A-19. Production, paving, and ambient temperatures at the Iowa field site. Aggregate Mixture Date of Production Plant Mix Temp, F Paving Temp, F Ambient Temp, F Low- Absorptive Aggregates WMA Control 06.28.13 260–265 250–260 70–73 WMA Control + 30 °F 06.28.13 290–295 285–290 75–79 HMA Control 06.28.13 290–295 285 80–85 HMA Control + 30 °F 06.28.13 320–325 305 85–88 High- Absorptive Aggregates WMA Control 07.01.13 260 250 63–67 WMA Control + 30 °F 07.01.13 290 285 70–76 HMA Control 07.01.13 290–295 290 78–80 HMA Control + 30 °F 07.01.13 305–310 295 80–81 Equipment Type Manufacturer Model Paver ROADTEC RP 195 Breakdown-Intermediate Roller (Steel-wheeled) HAMM HD + 120 VV-HV Finish Roller (Steel-wheeled) HAMM HD 12 VV Table A-20. Paving equipment used at the Iowa field site. Sample Type Material Point of Sampling Lab Mixed, Lab Compacted Fine Aggregate Stockpile Coarse Aggregate Stockpile RAP 1 and RAP 2 Stockpile PG 58-28 Asphalt Terminal Plant Mixed, Lab Compacted Loose Mix Truck at Plant Plant Mixed, Field Compacted Road Cores Travel Lane (random locations) Table A-21. Materials sampling scheme at the Iowa field site.

A-29 PMPC Specimen Compaction Sixty-four 6-in . (150-mm) diameter and 2 .4-in . (61-mm) tall specimens were compacted using plant mix at nearby Iowa State University’s civil engineering laboratory . The time required to haul the loose mix from the collection point (truck at the plant) to the Iowa State University laboratory was approx- imately 15 minutes . Plant loose mix collected at the truck at plant was quickly brought to the laboratory and placed in the oven to achieve the desired compaction temperature for that particular mixture . The time required from mixture produc- tion to specimen compaction varied between 1 and 2 hours for any given mixture . Specimens were compacted using a Troxler Superpave gyratory compactor to 7 ± 1 percent AV content . Florida Interstate 95 Rest Area (FL Parking) General Description This section summarizes the mixture production and con- struction of four test sections for a field evaluation project near Jacksonville, Florida, in July 2013 to investigate the effect of short-term aging on HMA and WMA using low- and high- absorption aggregate materials . The test sections were con- structed in the parking lot of the Florida Welcome Center on the southbound direction of I-95 . The WMA technology used on this project was an asphalt foaming system incorporated in a unitized counter-flow drum developed by Astec Industries, also known as the Astec Double Barrel® Green (DBG) system . Four mixtures (two HMA and two WMA) were produced using two different aggregate sources, including granite (low absorption) and limestone (high absorption) . The granite HMA and WMA mixtures were paved on July 17, and the limestone HMA and WMA mixtures were paved on July 18 . The contractor for this project was Duval Asphalt whose plant was located in Jackson- ville, Florida . Mix Designs The mixtures produced for this project were based on two 0 .5-in . (12 .5-mm) NMAS Superpave mix designs, with a design compaction effort of 75 gyrations . The first mix design used Martin Marietta granite aggregates from Georgia, and the other mix design used Cemex limestone aggregates shipped in from Miami, Florida, specifically for this project . Each design used 25 percent RAP . The RAP was from mul- tiple sources and crushed to 0 .5 in . (12 .7 mm) . The base binder used in each mixture was a PG 58-22 binder supplied by Marathon Oil in Jacksonville, Florida . A liquid anti-strip, LOF 6500, supplied by ArrMaz was used at 0 .5 percent by weight of the binder as an anti-stripping agent for the two mix designs . Each mix design was produced first at HMA temperatures then at WMA temperatures using the Astec DBG foaming system at 2 percent water by weight of the binder . The mate- rial percentages in the mix design and production for each mixture are shown in Tables A-22 and A-23 . The same per- centages were used throughout for both granite mixtures . A slight aggregate change was made about halfway through production of the limestone HMA, and the change was kept for the rest of the HMA production and the entirety of the WMA limestone production . Table A-24 summarizes the design aggregate gradation, design volumetric properties, specifications, and allowable tolerances . Aggregate Type Mix Design, % Production HMA, % WMA, % #7 Granite 20 23 23 #89 Granite 25 18 18 W-10 Screenings 17 28 28 M-10 Screenings 8 0 0 Local Sand 5 6 6 −0.5" Crushed RAP 25 25 25 Total AC 5.1 5.0 5.0 Table A-22. Aggregate percentages for binder content for granite mixtures. Aggregate Type Mix Design, % Production 1st Part of HMA Production, % 2nd Part of HMA Production and All of WMA, % #7 Limestone 20 20 21 #89 Limestone 18 20 20 Screenings 37 35 34 −1/2" Crushed RAP 25 25 25 Total AC 6.8 6.7 6.7 Table A-23. Aggregate percentages and binder content for limestone mixtures.

A-30 Production The Astec DBG plant (Figure A-42) used to produce the mix- tures for this field evaluation was located in Jacksonville, Flor- ida, approximately 30 mi from the site . Figure A-43 shows the Astec DBG multiple-nozzle foaming manifold used at the plant . The production of the granite HMA began at about 8:30 a .m . on July 17 and lasted until approximately 11:00 a .m . The production of the granite WMA began at about 12:30 p .m . the same day and lasted until approximately 2:30 p .m . The production of the limestone HMA began the next day on July 18 at about 7:30 a .m . and lasted until approximately 10:30 a .m . The production of the limestone WMA began about 12:00 p .m . and lasted until approximately 2:00 p .m . that same day . Table A-25 summarizes the production temperatures . Mixture Properties The mixtures were sampled at the plant to fabricate speci- mens in the NCAT mobile laboratory on site and in the main NCAT laboratory for determining mixture volumetric and performance properties . Moisture Content and Volumetric Properties The moisture content of plant-produced loose mix was determined based on two samples for each mixture in accor- dance with AASHTO T 329, “Moisture Content of HMA by Oven Method .” Each sample was approximately 1000 g . The samples were heated to a constant mass (less than 0 .05 per- cent change), as specified in AASHTO T 329 . The average moisture contents were 0 .06 percent and 0 .10 percent for the HMA and WMA using granite and Sieve Size mm JMF Granite Control Points Granite JMF Limestone Control Points Limestone 19.0 (3/4") 100 100 100 100 12.5 (1/2") 97 89–100 99 89–100 9.5 (3/8") 88 Max. 89 88 Max. 89 4.75 (#4) 60 — 66 — 2.36 (#8) 43 28–58 52 28–58 1.18 (#16) 34 — 36 — 0.6 (#30) 28 — 25 — 0.3 (#50) 22 — 17 — 0.15 (#100) 13 — 7 — 0.075 (#200) 4.5 2–10 4.5 2–10 Asphalt Content, % 5.1 — 4.0 — AV, % 4 — 14.5 — VMA, % 14.0 — 72.0 — VFA, % 71.0 — 0.9 — D/A Ratio 1.0 — 4.0 — Table A-24. Mix design gradation, asphalt content, and volumetrics for Florida mixtures. Figure A-42. Duval asphalt DBG drum plant in Jacksonville, Florida. Figure A-43. DBG multiple-nozzle foaming manifold used in Jacksonville, Florida.

A-31 was approximately 30 mi from the site, and the haul time was 40 minutes to 1 hour . Figure A-45 shows the test section layout and Figure A-46 shows the paving site in relation to the plant . The paver used for this project was a RoadTec RP190, as shown in Figure A-47 . The temperature of the mixture was measured every 5 to 20 minutes both in the auger and behind Temperature HMA Granite WMA Granite HMA Limestone WMA Limestone Average, °F 306.1 272.4 307.8 267.1 Standard Deviation, °F 4.9 5.6 9.0 12.2 Table A-25. Production temperatures for Florida mixtures. Figure A-44. NCAT mobile laboratory on site in Jacksonville, Florida. Table A-26. Design gradation, asphalt content, and volumetrics for plant-produced granite mixtures. Property JMF Granite HMA Granite WMA Granite Control Points Sieve Size % Passing 19.0 mm (3/4") 100 100.0 100.0 100 12.5 mm (1/2") 97 98.9 99.1 89–100 9.5 mm (3/8") 88 86.9 88.4 Max. 89 4.75 mm (#4) 60 55.6 58.0 — 2.36 mm (#8) 43 40.5 41.5 28-58 1.18 mm (#16) 34 31.7 32.2 — 0.60 mm (#30) 28 26.5 26.9 — 0.30 mm (#50) 22 22.0 22.1 — 0.15 mm (#100) 13 12.1 11.7 — 0.075 mm (#200) 4.5 5.6 5.1 2–10 Asphalt Content (%) 5.10 4.50 4.67 — Gmm 2.508 2.537 2.548 — Gmb 2.408 2.442 2.439 — AV (%) 4.0 3.7 4.3 — VMA (%) 14.0 12.9 13.1 — VFA (%) 71.0 71.0 67.5 — Dust/Binder 1.0 1.45 1.36 — Pba (%) 0.57 0.67 0.97 — Pbe (%) 4.30 3.85 3.74 — 0 .0 percent and 0 .04 percent for the HMA and WMA mixtures using limestone, respectively . Specimens were compacted to the Ndesign (75 gyrations) in the Superpave gyratory com- pactor . These volumetric samples were plant mixed and lab compacted on site in the NCAT mobile laboratory so that the mixtures would not have to be reheated, which has been shown to affect asphalt absorption and other volu- metric properties . The NCAT mobile laboratory on site is shown in Figure A-44 . The samples were placed in an oven for a short time after sampling only to get back up to the compaction temperature . Water absorption levels were low (<2 percent); therefore, bulk specific gravity (Gmb) was determined in accordance with AASHTO T 166 . The mix- tures were also brought back to the main NCAT laboratory where the asphalt content and gradation of each mixture were tested according to AASHTO T 308 and AASHTO T 30, respectively . The results from this testing are shown in Tables A-26 and A-27 for the mixtures with granite and limestone . Construction The HMA and WMA mixtures were placed in the park- ing lot of the Florida Welcome Center on the southbound direction of I-95 . The plant used for this field evaluation was an Astec DBG plant located in Jacksonville, Florida . The plant

A-32 Table A-27. Design gradation, asphalt content, and volumetrics for plant-produced limestone mixtures. Property JMF Limestone HMA Limestone WMA Limestone Control Points Sieve Size % Passing 19.0 mm (3/4") 100 100.0 100.0 100 12.5 mm (1/2") 99 99.9 99.5 89–100 9.5 mm (3/8") 88 90.7 89.2 Max. 89 4.75 mm (#4) 66 67.1 63.8 — 2.36 mm (#8) 52 52.6 50.2 28–58 1.18 mm (#16) 36 38.5 37.4 — 0.60 mm (#30) 25 29.2 28.5 — 0.30 mm (#50) 17 21.2 20.6 — 0.15 mm (#100) 7 11.0 10.7 — 0.075 mm (#200) 4.5 5.9 5.8 2–10 Asphalt Content (%) 6.80 6.56 6.41 — Gmm 2.342 2.350 2.363 — Gmb 2.249 2.266 2.271 — AV (%) 4.0 3.6 3.9 — VMA (%) 14.5 14.1 13.8 — VFA (%) 72.0 74.7 71.9 — Dust/Binder 0.9 1.23 1.29 — Pba (%) 1.65 1.88 2.04 — Pbe (%) 4.80 4.80 4.50 — Figure A-45. Layout of test sections in Jacksonville, Florida.

A-33 Figure A-46. Location of plant and paving site in Jacksonville, Florida.

A-34 the paver with a handheld temperature gun . Tables A-28 and A-29 show the temperatures of the mixture in the auger and behind the screed, respectively . Both granite mixtures were compacted using two break- down rollers in tandem operating in static mode . The rolling pattern used was seven passes on each side of the mat in the static mode . A finishing roller was not used for the granite mixtures . For both limestone mixtures, the same breakdown rollers were used, but only five passes in the static mode were needed to achieve density . A rubber tire roller was used to roll each joint once on the limestone mixtures . This was done an hour or more after placement, once the mix- ture had cooled significantly, and according to the contrac- tor, it was done mainly for aesthetic purposes . Figure A-48 shows one of the breakdown rollers compacting the granite HMA mixture . Figures A-49 and A-50 show examples of the compacted mat for the granite and limestone mixtures, respectively . Weather data were collected hourly at the paving location using a handheld weather station . There was no rain dur- ing the construction of either mixture . Table A-30 shows the ambient temperatures, wind speed, and humidity for both mixtures produced . Field Cores for Further Testing After construction, ten 6-in . (150-mm) cores were obtained from each test section . These cores were taken back to the laboratory, and the density of the surface layer was deter- mined after trimming from the underlying layers . The densi- ties were determined in accordance with AASHTO T 166 . If the water absorption was higher than 2 percent, the samples Figure A-47. RoadTec paver used in Jacksonville, Florida. Table A-28. Temperatures of mixture in the auger in Jacksonville, Florida. Mixture Type HMA Granite WMA Granite HMA Limestone WMA Limestone Temperature, °F. Avg. 278.6 251.8 278.6 241.4 Std. Dev. 8.1 9.0 8.1 8.0 Minimum 253.5 233.5 253.5 226.0 Maximum 297.0 266.5 297.0 255.5 Table A-29. Temperatures of mixture behind screed in Jacksonville, Florida. Mixture Type HMA Granite WMA Granite HMA Limestone WMA Limestone Temperature, °F. Avg. 276.6 251.6 276.6 242.9 Std. Dev. 9.9 6.4 9.9 9.0 Minimum 260.5 241.5 260.5 227.0 Maximum 296.5 259.5 296.5 258.5 Figure A-48. Breakdown roller compacting granite HMA.

A-35 were then tested according to AASHTO T 331 . Average test results are shown in Table A-31 . Average core densities were virtually the same for both mixtures, with the WMA aver- aging just slightly denser results . This was expected since it has often been observed that WMA technologies can provide increased compactability compared to HMA, even at lower temperatures . City of Indianapolis, Residential Streets (IN Residential) General Description This report documents the production, construction, and materials properties for a field evaluation site in Indianap- olis, Indiana . The test site consisted of four test sections constructed with four mixtures based on the same mix design but produced at hot and warm mix temperatures by two plants, a modified batch plant and a modified counter- flow drum plant . The four test sections were constructed on several residential city streets on the west side of India- napolis beginning at the intersection of North Tibbs Avenue and West 21st Street from August 19 through 22, 2013 . The contractor was Rieth-Riley Construction, Inc ., and its two plants were located at Rieth-Riley’s Kentucky Avenue facility in Indianapolis . In the first 2 days of production, the batch plant and then the drum plant were used to produce two HMA mixtures . On the third day of production, the modified batch plant was used to produce a WMA mixture using WMA additive Advera at a rate of 0 .25 percent by weight of total mixture (5 lb/ton) . On the fourth day of production, the Astec single counter-flow barrel drum plant was used to produce another Figure A-49. Example of compacted granite mixture mat. Figure A-50. Example of compacted limestone mixture mat. Table A-30. Weather conditions during construction in Jacksonville, Florida. Mixture HMA Granite WMA Granite HMA Limestone WMA Limestone Ambient Avg. Temp. (°F) 92.6 96.4 92.4 90.9 Range 84.6–98.7 93.1–100.0 89.9–95.1 90.5–91.2 Wind Speed (mph) 1.7 2.13 1.3 1.3 Range 1.0–3.0 1.5–3.4 1.0–2.1 0.6–1.7 Humidity, % 55.0 48.2 52.6 52.4 Range 46.0–92.6 41.3–52.9 49.4–56.4 52.0–52.6 Table A-31. In-place density from cores in Jacksonville, Florida Test Statistic HMA Granite WMA Granite HMA Limestone WMA Limestone In-place Density (%) Average 93.4 93.1 92.1 91.7 Standard Deviation 1.0 0.8 1.1 0.9

A-36 WMA using the foaming technology AquaFoam® at 2 per- cent by weight of the binder . All the mixtures were produced based on the same mix design . Mix Designs The asphalt mixtures were produced based on a 0 .37 in . (9 .5 mm) NMAS Superpave mix design, with a design compac- tion effort of 75 gyrations . The mix design contained 25 percent RAP crushed to 0 .5 in . (12 .7 mm) . The base binder used for all mixtures was a PG 64-22 supplied by Interstate Asphalt out of Chicago and Peoria, Illinois . No anti-strip agent was used for any of the mixtures produced . The aggregate consisted of lime- stone and natural sand from the Martin Marietta quarry next to Rieth-Riley’s facility . The same material percentages were used throughout production of all four mixtures . Table A-32 shows the design and production percentages . The design aggregate gradation, optimum asphalt content, design volumetrics, speci- fications, and allowable tolerances are shown in Table A-33 . Production Two different plants were used to produce the four mixtures evaluated in this project, a modified batch plant and a counter- flow drum plant . Both of them were located at Rieth-Riley’s Kentucky Avenue facility in Indianapolis, Indiana . The distance to the site was approximately 7 mi . The batch and drum plants can be seen in Figures A-51 and A-52, respectively . Production of the HMA mix using the batch plant began on August 19, 2013, at about 6:40 a .m . and lasted until approximately 6:00 p .m . The total production was approxi- mately 1,250 tons . Production of the HMA using the drum plant started on August 20 at approximately 7:00 a .m . and lasted until 4:00 p .m . The total mixture production this day was approximately 760 tons . Aggregate Type Mix Design, % Production, % #11 Limestone 33.0 33.5 Manufactured Sand 30.5 30.9 Natural Sand 10.0 10.1 Crushed RAP 25.0 25.5 Baghouse Fines 1.5 Return 100% Total AC 5.8 5.8 Table A-32. Aggregate and binder percentages used in mix design and production for Indianapolis field site. Sieve Size JMF Control Points 19.0 mm (3/4") 100 100 12.5 mm (1/2") 100 100 9.5 mm (3/8") 96.8 100 4.75 mm (#4) 68.3 <90 2.36 mm (#8) 46.3 32–67 1.18 mm (#16) 29.7 — 0.6 mm (#30) 19.2 — 0.3 mm (#50) 10.5 — 0.15 mm (#100) 6.4 — 0.075 mm (#200) 5.1 2–10 AC, % 5.8 — AV, % 4 — VMA, % 15.8 — VFA, % 74.7 — D/A Ratio 1.0 — Pbe 5.2 — Table A-33. Design gradation, asphalt content, and volumetrics for Indianapolis mix design. Figure A-51. Rieth-Riley’s modified batch plant in Indianapolis, Indiana.

A-37 On the third day of production, August 21, a WMA mix was produced using the modified batch plant with the WMA additive Advera . Mixture production started at approxi- mately 7:20 a .m . and lasted until 11:00 a .m . The total mix- ture production that day was approximately 770 tons . On the last day of production, August 22, the mixture was produced using the Astec single counter-flow barrel drum plant with the WMA foaming technology AquaFoam . The production started at approximately 7:20 a .m . and ended at about 4:30 p .m . A total of 1,000 tons was produced that day . Table A-34 summarizes the production temperature data for the four mixtures . Mixture Properties Each mixture was sampled during production and then used to fabricate a variety of specimens for determining moisture, volumetric, and performance properties in both the NCAT mobile laboratory and main laboratory . AASHTO T 329, “Moisture Content of HMA by Oven Method,” was followed to evaluate the moisture content of loose plant-produced mix (two samples per mixture) . Each sample was approximately 1000 g . The samples were heated to a constant mass (less than 0 .05 percent change), as defined by AASHTO T 329 . The average moisture contents were 0 .11 percent and 0 .10 percent for the HMA and WMA that were produced using the batch plant and 0 .08 percent for the HMA and WMA mix- tures produced by the drum plant . Figure A-52. Rieth-Riley’s counter-flow drum plant in Indianapolis, Indiana. Temperature Batch HMA Batch WMA Drum HMA Drum WMA Average, °F 305.4 273.2 300.4 271.4 Standard Deviation, °F 8.6 15.9 9.3 5.5 Table A-34. Production temperatures for Indianapolis field site. Volumetric specimens were PMLC on site in the NCAT mobile laboratory (Figure A-53) so that the mixtures would not have to be reheated, which has been shown to affect asphalt absorption and other volumetric properties . The specimens were compacted to 75 gyrations in the Superpave gyratory compactor . The samples were placed in an oven for a short time after sampling only to get back up to the compaction tempera- ture . Water absorption levels were low (<2 percent), therefore bulk specific gravity (Gmb) was determined in accordance with AASHTO T 166 . The mixtures were also brought back to the main NCAT laboratory where the asphalt content and grada- tion of each mixture were tested according to AASHTO T 308 and AASHTO T 30, respectively . The results from this testing are shown in Table A-35 . Construction The HMA and WMA mixtures were placed in several residential city streets on the west side of Indianapolis beginning at the intersection of North Tibbs Avenue and West 21st Street . The paving site was approximately 7 mi from the plant . With traffic, the haul distance was approxi- mately 15 to 25 minutes . Figure A-54 shows the test section layout and Figure A-55 shows the paving site in relation to the plant . The paver used for this project was a RoadTec RP175, as shown in Figure A-56 . The target pavement thickness was 1 .5 to 2 .0 in . (38 to 50 mm) . The temperature of the mixture was Figure A-53. NCAT mobile laboratory on site in Indianapolis, Indiana.

Property JMF HMA Batch WMA Batch HMA Drum WMA Drum Control Points Sieve Size % Passing 19.0 mm (3/4") 100.0 100.0 100.0 100.0 100.0 100 12.5 mm (1/2") 100.0 100.0 100.0 100.0 100.0 100 9.5 mm (3/8") 96.8 97.0 96.8 97.7 97.0 100 4.75 mm (#4) 68.3 66.1 66.3 73.3 69.3 <90 2.36 mm (#8) 46.3 44.7 45.9 49.2 43.8 32–67 1.18 mm (#16) 29.7 29.9 31.5 31.1 27.6 — 0.60 mm (#30) 19.2 20.3 21.8 19.8 17.5 — 0.30 mm (#50) 10.5 12.1 13.4 11.7 10.2 — 0.15 mm (#100) 6.4 8.2 9.2 8.3 7.1 — 0.075 mm (#200) 5.1 5.9 6.8 6.1 5.1 2–10 Asphalt Content (%) 5.8 6.00 6.05 6.39 6.07 — Gmm 2.452 2.451 2.448 2.446 2.455 — Gmb 2.354 2.390 2.406 2.368 2.348 — AV (%) 4.0 2.5 1.7 3.2 4.4 — VMA (%) 15.8 13.3 12.8 14.5 14.9 — VFA (%) 74.7 81.2 86.5 78.0 70.8 — Dust/Binder 1.0 1.26 1.43 1.24 1.10 — Pba (%) 0.69 1.41 1.39 1.58 1.53 — Pbe (%) 5.15 4.67 4.74 4.91 4.63 — Table A-35. Gradation, asphalt content, and volumetrics for plant-produced mixtures in Indianapolis, Indiana. Figure A-54. Layout of test sections in Indianapolis, Indiana.

A-39 Figure A-55. Locations of plant and paving site in Indianapolis, Indiana.

A-40 Figure A-56. RoadTec paver used in Indianapolis, Indiana. Temperature Batch HMA Batch WMA Drum HMA Drum WMA Average, °F 287.3 246.0 269.5 251.5 Standard Deviation, °F 12.8 9.2 8.5 5.7 Table A-36. Temperatures of mixture in the auger in Indianapolis, Indiana. Temperature Batch HMA Batch WMA Drum HMA Drum WMA Average, °F 283.9 243.1 265.5 250.1 Standard Deviation, °F 10.9 9.9 8.5 5.9 Table A-37. Temperatures behind the screed in Indianapolis, Indiana. Figure A-57. Breakdown and finishing rollers compacting the HMA drum mix. Figure A-58. Example of compacted HMA (batch plant). measured every 10 to 30 minutes both in the auger and behind the paver with a handheld temperature gun . Tables A-36 and A-37 show the temperatures of the mixture in the auger and behind the screed, respectively . All the mixtures were compacted using both a breakdown and finishing roller . Figure A-57 shows the two rollers com- pacting the HMA mixture produced by the drum plant . Fig- ures A-58 and A-59 show examples of the compacted mat for the HMA and WMA mixtures produced using the batch plant . Weather data were collected hourly at the paving loca- tion using a handheld weather station . Table A-38 shows the ambient temperatures, wind speed, and humidity for both mixtures produced . Field Cores for Further Testing After construction, ten 6-in . (150-mm) cores were obtained from each mixture section . These cores were taken back to the laboratory and the density of the surface layer was deter- mined after trimming from the underlying layers . The densi- ties were determined in accordance with AASHTO T 166 . If

A-41 Figure A-59. Example of compacted WMA (batch plant). Mixture Batch HMA Batch WMA Drum HMA Drum WMA Ambient Avg. Temp. (°F) 87.0 87.3 88.3 87 Range 72–93 77.5–94.8 78.5–95.7 74.2–93.7 Wind Speed (mph) 0.4 0.6 1.03 0.5 Range 0–1.8 0–1.3 0–2.7 0–1.2 Humidity, % 42.3 52.9 44.1 53.9 Range 30–68.5 37.7–71.1 36.5–63.8 44.2–75.8 Table A-38. Weather conditions during construction in Indianapolis, Indiana. Test Statistic Batch HMA Batch WMA Drum HMA Drum WMA In-place Density (%) Average 90.1 91.3 90.9 90.3 Standard Deviation 1.77 1.50 2.16 0.66 Table A-39. In-place density from cores in Indianapolis, Indiana. the water absorption was higher than 2 percent, the samples were then tested according to AASHTO T 331 . Average test results are shown in Table A-39 . Average core densities were virtually the same for both mixtures, with the WMA aver- aging just slightly denser results . This was expected since it has often been observed that WMA technologies can provide increased compactability compared to HMA, even at lower temperatures . Midland–Odessa City Street (TX II Local) General Description Midland–Odessa, Texas, test sections were designed to exam- ine the effects of binder sources and plant types on the aging of HMA . This section was located on a recently built city street for a new subdivision in Odessa, Texas . Reece Albert, Inc ., a general construction contractor, produced the mixtures and paved the street . At researchers’ request, the contractor agreed to use asphalt from two different binder sources and two dif- ferent HMA plants . The street was paved in the middle of April 2014 . This curb-and-gutter type city street has two lanes in each direction with a turn lane at the center . Including the shoulder, the total width of paving was 61 ft (18 .6 m) . Four subsections (two binders × two plants), each with approximately 1200 ft (366 m) in length, were laid side by side . Figure A-60 shows the layout of the test sections . Mixtures and Materials Only one type of aggregate gradation was used for all four mixtures . This project used TxDOT’s Type D (equivalent to 0 .37-in . [9 .5-mm] NMAS aggregate size) mixture designed with limestone aggregate from nearby Parks Bell quarry . The contractor laid mixtures with this same design for several other projects in the past . Figure A-61 presents the summary of mix design . The mixture was designed using Texas gyratory Figure A-60. Midland–Odessa test sections.

Figure A-61. Mix design used in Midland–Odessa field site.

A-43 compactor . The design asphalt content was 6 .2 percent . The mixture did not use hydrated lime or any other admixture . The project used PG 64-22 unmodified binder from two different sources . The sources were Binder A refinery located at Big Spring in West Texas and Binder V refinery located at Sunray, Texas . Binder A refinery is approximately 60 miles from the project site and uses crude oil from a west Texas source . Binder V refinery at Sunray is located in the northwest Texas panhandle area . Plants Description As part of the experimental design, the contractor used two HMA plants and two different aggregate sources, keeping other variables same . Albert Reece, Inc . owns both plants . Figures A-62 and A-63 show the batch plant and drum plant, respectively . Batch Plant The batch plant was located approximately 25 mi from the job site . The hauling time was between 30 and 35 minutes . The batch plant was older—manufactured in 1957 . The production capacity of this plant is 100 tons/hour with a 2 .5-ton batch size . It had a 200-ton capacity silo . The plant also had two horizon- tal binder tans . It has a draft type emission-control system . Drum Plant Figure 63 shows the portable drum plant used in this proj- ect . This plant was located only 7 mi or 12 minutes from the project site . It was a counter-flow drum with a production capacity of 400 tons/hour . The model of the plant is CMI STD 400 triple drum . This 20-year-old plant had a 9-ft-diameter and 44-ft-long drum . The drum’s mixing zone was 12 ft long . This plant had a conventional bag house emission-control sys- tem . A partial amount of fines were returned back to the drum during production . It ran about 175 tons/hour production rate . Instead of a silo, the plant had a 50-ton capacity surge bin . Mixture Production For a given binder source, each plant produced approximately 200 to 225 tons . Production started at slightly higher tempera- tures at the beginning . The silo storage time of batch plant- produced mixture was about 30 to 40 minutes . The silo (surge bin) storage time of the drum plant was approximately 10 to 15 minutes . Each of the 2 days of mixture production began with the batch plant followed by the drum plant . Belly dump trucks used for hauling mixtures had tarp to cover the mixtures . Table A-40 presents the mixtures production summary . Construction This asphalt mixture layer was placed directly on top of a freshly constructed flexible base layer . The 6- to 8-in . (15- to 20-cm) thick flexible base layer was prime-coated a few days before the HMA was placed . Once the belly dump trucks released the mixtures on the road, a windrow elevator picked up the mixtures and dropped them into the paver chute as shown in Figure A-64 . The paving width and thickness of the sections Figure A-62. Midland–Odessa batch plant. Figure A-63. Midland–Odessa drum plant. Mixture Binder Source Plant Type Date of Production Plant Mix Temp, F Paving Temp, F Ambient Temp, F BPA Binder A Batch 04/16/14 325–330 270–280 52–60 DPA Binder A Drum 04/16/14 325–330 270–280 60–65 BPV Binder V Batch 04/17/14 325–330 280–290 70–75 DPV Binder V Drum 04/17/14 325–330 280–285 75–78 Table A-40. Production, paving, and ambient temperatures at the Midland–Odessa field site.

A-44 Figure A-64. Paving with windrow operation at the Midland–Odessa field site. Equipment Type Manufacturer Model Windrow Elevator Lincoln 660 AXL Paver Vogel (Wirtgen) 5203-2i Vibratory Steel-Wheeled Roller HAMM AG HD + 140 VO Pneumatic Roller Caterpillar CAT 5378 Steel-Wheel Finish Roller (4 ft) Table A-41. Paving equipment used at the Midland–Odessa field site. Figure A-65. Loose mix sampling from truck in Midland–Odessa batch plant. were 15 ft (4 .6 m) and 2 in . (50 mm), respectively . Table A-41 provides the list of paving equipment used during HMA layer construction . The vibratory steel-wheeled roller immediately followed the paver . The pneumatic roller followed the vibratory roller once the mat temperature was approximately 180°F (82°C) . The contractor used a small 4-ft (1 .2-m) wide steel-wheel fin- ish roller at the end . Typically, the vibratory roller made two vibratory passes followed by one static pass . The pneumatic roller made five passes . Sample Collection Plant mix was collected from the trucks at plants by climb- ing on scaffolding . Figures A-65 and A-66 show the sample collection at batch and drum plant, respectively . Samples were collected usually from the fifth or sixth truck when the plant temperatures become stable . In each case, loose samples were split as shown in Figure A-65 . The materials sampling scheme is presented in Table A-42 . The mixture sample collected from the plant was immedi- ately brought back to the FHWA mobile laboratory located within the drum plant facility for compaction into two speci- mens of two sizes (6 .0 × 2 .4 in . [150 × 61 mm], 6 .0 × 7 .0 in . [150 × 175 mm]) . The FHWA mobile laboratory crew helped the research team by collecting both binders from the trans- port truck while they were delivering binders at the drum plant facility . With the help of the paving contractor, the research team also collected thirty-two 6-in . (150-mm) diameter road cores from four test sections . Road cores were obtained from the

A-45 Sample Type Material Point of Sampling Lab Mixed, Lab Compacted Fine Aggregate Stockpile Coarse Aggregate Stockpile PG 64-22 Asphalt Transport Truck PG 76-22 Asphalt Transport Truck Plant Mixed, Lab Compacted Loose Mix Windrow Plant Mixed, Field Compacted Road Cores Center of the Paving Width Table A-42. Materials sampling scheme for the Midland–Odessa field site. Figure A-66. Loose mix sampling from truck in Midland–Odessa drum plant. center of the 15-ft . (4 .6-m) wide paving mat at 80-ft . (24 .4-m) intervals excluding the first 400 ft . (122 m) of paving . Field Specimen Compaction Forty-four 6-in . (150-mm) diameter specimens were com- pacted on site using plant mix at the FHWA mobile laboratory located within the drum plant premises . Thirty-two of them were 2 .4 in . (61 mm) and 12 of them were 7 .0 in . (175 mm) tall . The taller specimens were cored and saw cut to conform to E* testing . Plant loose mix collected at the plants was quickly brought to the mobile laboratory and placed in the oven 1 to 2 hours to achieve respective compaction temperature for that particular mixture . The FHWA mobile laboratory crew com- pacted these specimens with an IPC Servopac Superpave gyra- tory compactor to 7 .0 ± 1 .0 percent AV content .