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D-1 A P P E N D I X D Wisconsin Construction Report The rehabilitation of the pavement surface for Wisconsin State Highway 36 (SH36) was done in the fall of 2016. SH36 is a two-way divided road located near Muskego, Wisconsin. Muskego itself is located in the southeastern portion of Wisconsin, about 20 miles west from Lake Michigan (Milwaukee area). The south bound (SB) is surfaced with concrete pavement while the north bound (NB) is surfaced with asphalt concrete (AC). The typical road bed for the NB was 38-feet including two 12-feet travel lanes with a structure that consists primarily of Portland cement concrete (PCC) with asphalt overlays of variable thickness constructed over the years. In addition, the 8-feet asphalt paved shoulder sits over a granular base. The SH36 rehabilitation project included localized repairs on jointed Portland cement concrete (JPCC) pavement in the SB and milling 2â of existing AC pavement and replacement with a 2â overlay in the north bound (NB). The contractorâs rehabilitation activities relevant to this project included approximately 3 miles of AC pavement on the NB outer lane and shoulder of SH36. The project overview is presented in Figure D.1 with details of the test section locations provided in Table D.1. Figure D.1: Project Overview.
D-2 Evaluating the Effects of Recycling Agents on Asphalt Mixtures with High RAS and RAP Binder Ratios replacement) satisfied all WisDOT mixture requirements (Design HR_250-0316-2016) including volumetrics and Tensile Strength Ratio (TSR). Project sections 1 through 4 specified in Table D.1 are considered plausible alternatives to the contractorâs design 250-0052-2016 (Section 5). In this project sections 1, 3, 4, and 5 were evaluated. Table D.1: Description of Experimental Sections Constructed in SH36 Section 1 Section 2 Section 3 Section 4 Section 5 Label HR 52-34 HR 58-28 3% HR 58-28 V2 HR 58-28 Control 58-28 DOT Control Description 36% RAP Binder PG 52-34 36% RAP Binder PG 58-28 Regressed AV 3% 36% RAP Binder PG 58-28 + 1.2% V2 36% RAP Binder PG 58-28 - Control 27% RAP Binder PG 58-28 â DOT Control Design HR_250-0316-2016 50-0316- 2016_3.0 HR_250- 0316-2016 HR_250- 0316-2016 WisDOT #250-0052- 2016 Additive NA NA 1.2% V2 1815 NA NA Paving Date 9-19-2016 9-19-2016 9-26-2016 9-26-2016 9-26-2016 Coord. Start 42.882070, - 88.046489 42.882534, - 88.045854 42.854431, - 88.111383 42.857861, - 88.101445 42.860935, - 88.092682 Coord. End 42.873548, - 88.057185 42.888704, - 88.038507 42.857178, - 88.103563 42.860563, - 88.093735 42.864691, - 88.081787 Cores NB Outer lane NB Outer lane NB Outer lane NB Outer lane NB Outer lane Current Wisconsin DOT (WisDOT) specifications allow up to 25% binder replacement for upper AC layers (Section 460 Hot Mix Asphalt Pavement). Binder replacement can be achieved by incorporation of reclaimed asphalt pavement (RAP), fractionated RAP (FRAP), or recycled asphalt shingles (RAS) that cannot exceed 5% by weight of the aggregate blend. The contractorâs approved RAP inclusive mix design (Design 250-0052-2016) consists of a 12.5mm Nominal Maximum Aggregate Size (NMAS) E-3 (WisDOT specifications) that considers 22.8% binder replacement. The contractor demonstrated that an alternative design with higher percentage of RAP (31% binder
Wisconsin Construction Report D-3 Figure D.2: Existing Pavement Condition. The asphalt mixtures were produced at an asphalt plant in Muskego (Figure D.3). Most of the area was paved, including the location of the aggregate stockpiles. The stockpiles were not covered (except for the RAS, which was not used in this field project). The paved surface helped control the moisture content in the stockpiles. The aggregates were extracted and crushed locally. The natural sand was extracted from the same quarry. The existing pavement (outer lane and shoulder as shown in Figure D.2) exhibited severe transverse cracking throughout. Cracks were mostly evenly spaced, and the 2 inch milling operation did not remove the entire cracked pavement. During the coring process described subsequently, a core was found cracked all through the old layers. The pavement cracking is attributed to joint reflection and/or thermal cracking. The paving operation proceeded as a 2â overlay without full depth structural repair. The pavement structure on the NB lanes of SH36 consisted of AC over JPCC constructed on top of a granular base as indicated in the project plans. During the coring process, the thickness of AC layers was found to be variable across the project. Sections 1 and 2 had AC layers adding up to around 8 to 10 inches (including the 2 inch overlay) while AC layers in sections 3, 4, and 5 added up to about 4 to 6 inches.
D-4 Evaluating the Effects of Recycling Agents on Asphalt Mixtures with High RAS and RAP Binder Ratios were used in this field project. The aggregate bins, point of aggregate inclusion, and point of inclusion of DEG (baghouse filler) are shown in Figure D.4. Two bins were used for RAP inclusion (Figure D.5), one with crushed RAP passing the Â½-inch sieve while the second RAP fraction had up to 3 inch RAP agglomerates. The total 36% RAP was achieved by adding 20% of passing 3- inch RAP and 16% passing Â½-inch RAP. The combined RAP passed through an in-line Â¾-inch screening system. All the RAP agglomerates larger than the screening size were transferred to an in-line crushing system, thus the entire RAP added to the mixtures passed the required Â¾-inch screening. Both fractionated RAP sources were reported to have 4.65% asphalt content. The inclusion of asphalt binder is shown in Figure D.6. Section 3 included a recycling agent (V2) which was blended in-line with the PG 58-28 asphalt binder at a dosage of 1.2% by weight of binder. The âGreen Machineâ, a system commonly used for warm-mix additive and inclusion of anti-stripping agents, was used for dosing the recycling agent. V2 is a modified vegetable oil. Figure D.4: Production Details â Aggregates. Figure D.3: Asphalt Plant Overview. A drum plant was used to produce the hot mix asphalt (HMA), and production details are given in Figure D.4, Figure D.5, and Figure D.6. The plant had nine bins for aggregate inclusion, and four
Wisconsin Construction Report D-5 Figure D.5: Production Details - Recycled Materials. Figure D.6: Production Details â Binder and Recycling Agent (V2). The construction process is shown in Figure D.7. A tack coat was applied over the milled pavement surface prior to placement of the overlay. Two pavers were operating simultaneously, one paving the traffic lane (operating with a material transfer device) and the second paving the shoulder V2
D-6 Evaluating the Effects of Recycling Agents on Asphalt Mixtures with High RAS and RAP Binder Ratios (without a material transfer device). The rolling pattern included first a steel roller with vibration (hot), followed by a pneumatic roller (intermediate), and finally a steel roller with no vibration (cold). The time between production and placement was estimated to be about one hour for sections 1, 2, and 5. The silo storage time was about 20 to 30 min and hauling time was 30 min. The trucks had a minimum waiting time before transferring the asphalt mixture to the paver (or material transfer device for the traffic lane). The paving process was significantly slowed down during the last 400ft of section 3 (HR 58-28 + V2) due to the work required at the intersection with Thode Dr. The waiting time for the trucks at the paving site was about one hour for that last portion of section 3 and the starting of section 4 (HR 58-28 control). By the time section 5 was being paved, the process resumed normal pace. Figure D.7: Construction Process. Production and placement temperatures were monitored at the plant drum discharge, in the truck before leaving the asphalt plant, and during placement between the paver and roller 1 as shown in Figure D.8. The plant supervisor reported that production temperature was 320Â°F for all the mixtures throughout the project. The temperature readings and weather information are summarized in Table D.2. Measurements were primarily taken with a heat gun at the surface.
Wisconsin Construction Report D-7 Figure D.8: Temperature Readings. Table D.2: Production and Placement Temperatures (Â°F). Section 1 Section 2 Section 3 Section 4 Section 5 High temperature (Weather.com) 84 84 65 65 65 Ground temperature (Heat gun) 100 100 74 74 74 Pavement temperature (Heat gun) 108-110 108-110 92 92 92 Truck (QC/QA) 313 316 313 308 313 Paver to roller 1 (Heat gun) 270-280 255-260 270-275 255-280 260-280 Raw materials (i.e. aggregates, RAP, binders, recycling agent) and plant mix were collected as described in Figure D.1. All aggregates and RAP were in outdoor stockpiles, and a front loader assisted in preparing sampling piles from which materials were collected as shown in Figure D.1 a. Binders were sampled in line, right before injection into the plant drum (Figure D.1 b). Plant mixtures were sampled by dumping a small sampling pile on a clean paved surface as shown in Figure D.1 c. Mixture samples were taken for the contractor, WisDOT, and TTI simultaneously.
D-8 Evaluating the Effects of Recycling Agents on Asphalt Mixtures with High RAS and RAP Binder Ratios (a) Aggregates (b) Binder
Wisconsin Construction Report D-9 (c) Mixtures Figure D.9: Sampling Materials. Coring was performed during the same day of paving, and density gauge readings were taken a priori. Six cores were obtained per pavement section, all from the outer traffic lane of SH36. The coring process is illustrated in Figure D.10 with a bag of ice placed for about 15 min to ensure the asphalt mixture had cooled down. Cores were taken along the length of the entire asphalt pavement thickness, until the mixtures detached from the underlying Portland cement concrete (PCC) or granular base. Detailed locations, approximate core thickness, density gauge readings, and notes taken during the coring process are presented in Table D.3. Figure D.10: Coring.
D-10 Evaluating the Effects of Recycling Agents on Asphalt Mixtures with High RAS and RAP Binder Ratios Table D.3: Cores Description Section Core # Density (%Gmm) Reference Thickness (in) Notes 1 1 94.3 9.25 8-10" AC, probably on top of base. Rough aggregate surface observed 1 2 94.2 8.5 8-10" AC on top of PCC 1 3 NA 996+00 9.25 8-10" AC, probably on top of base. Rough aggregate surface observed 1 4 94.8 999+00 9.75 8-10" AC on top of PCC 1 5 94.4 1004+00 9.75 8-10" AC on top of PCC 1 6 95.3 1009+00 8 8-10" AC, probably on top of base. Rough aggregate surface observed 2 1 94.5 1019+00 NA 8-10" AC, probably on top of base. Rough aggregate surface observed 2 2 92.2 1021+00 NA 8-10" AC, probably on top of base. Rough aggregate surface observed 2 3 94.4 1026+00 NA 8-10" AC, probably on top of base. Rough aggregate surface observed 2 4 94 1030+00 NA 8-10" AC on top of PCC 2 5 95.5 1034+00 NA 8-10" AC on top of PCC 2 6 95.9 1038+00 NA Specimen broke during coring. 3 1 93 811+30 4.5 4" AC on top of PCC (10") 3 2 92.2 817+00 Broke 4" AC on top of PCC 3 3 95.5 819+00 4.5 5" AC on top of PCC 3 4 95.9 823+00 4.75 5" AC on top of PCC 3 5 93.2 827+00 4.75 5" AC on top of PCC 3 6 94.5 830+00 4 4" AC on top of PCC 4 1 93 839+00 5.25 6" AC on top of PCC 4 2 93.9 841+00 5 6" AC on top of PCC 4 3 96.3 844+00 4.5 5" AC on top of PCC 4 4 94.1 847+00 4.75 5" AC on top of PCC 4 5 93.8 mailbox 14650 4.75 5" AC on top of PCC 4 6 96 859+00 5.75 6" AC on top of PCC 5 1 96.1 865+00 5 6" AC on top of PCC 5 2 94.9 871+00 9 8+" AC on top of base 5 3 94.5 country club 5.75 6" AC on top of PCC 5 4 95.9 880+00 4.5 5" AC on top of PCC 5 5 95.7 885+00 4.5 5" AC on top of PCC 5 6 95.2 893+00 5 5" AC on top of PCC Mix design and quality control reports provided by the contractor are shown next.
Figure D.11: Mix Design â DOT Control (0-250-0052-2016)
Figure D.11: Mix Design â High RAP (0-250-0316-2016)
Wisconsin Construction Report D-13 Figure D.12: Section 1 â High RAP PG 52-34
D-14 Evaluating the Effects of Recycling Agents on Asphalt Mixtures with High RAS and RAP Binder Ratios 43-25 GP PAR hgiH â 1 noitceS :31.D erugiF
Wisconsin Construction Report D-15 Figure D.14: Section 2 - HR PG 58-28 Regressed AV 3%
D-16 Evaluating the Effects of Recycling Agents on Asphalt Mixtures with High RAS and RAP Binder Ratios Figure D.14: Section 2 - HR PG 58-28 Regressed AV 3%
Wisconsin Construction Report D-17 Figure D.15: Section 3 â HR PG 58-28 with 1.2% V2
D-18 Evaluating the Effects of Recycling Agents on Asphalt Mixtures with High RAS and RAP Binder Ratios lortnoC 82-85 GP RH â 4 noitceS :61.D erugiF
Wisconsin Construction Report D-19 Figure D.17: Section 5 â DOT Control PG 58-28