Section 401 — Asphalt Concrete Pavement By Gyratory Mix Design Method
BY GYRATORY MIX DESIGN METHOD
Description
401.01This work consists of constructing asphalt concrete pavement using HMA or WMA.
Material
401.02Conform to the following Subsections: Antistrip additive 702.05 Asphalt binder 702.01 Asphalt concrete aggregate 703.07 Mineral filler 725.05
Construction Requirements
401.03Composition of Mix (Job -Mix Formula). Provide asphalt concrete mixes of aggregate, asphalt binder, RAP, and additives that meet the applicable material requirements and the appropriate design parameters shown in Table 401-1 and can be placed and compacted as specified . Volumetric mix properties will be determined at N design according to AASHTO T 312 and AASHTO R 35. Short- term condition samples according to AASHTO R 30 at the manufacturer ’s recommended compaction temperature. Include the material finer than the No. 200 sieve when determining the AASHTO T 84 fine aggregate specific gravity and absorption. Apply asphalt concrete mix design requirements for HMA to the development of the WMA mix design. Provide modifications to the process required for WMA technology. Submit modifications to the asphalt concrete mix design process for WMA according to Appendix X.2 of AASHTO R 35 for approval. (a)RAP. Limit the quantity of RAP by mass in the JMF to 20 percent. (b)Baghouse fines. If used, document how baghouse fines are reintroduced and measured. Submit target values for the percent of baghouse fines reintroduced to the JMF if they are a separate stockpile. Table 401-1 Gyratory Asphalt Concrete Mix Design Requirements, AASHTO R 35
Design
ESAL
(Million) Gyratory Compaction Level (Percent Theoretical Maximum Specific Gravity, G mm) AASHTO T 312 Minimum Voids in the Mineral Aggregate (VMA) , percent(1)(4) Voids Filled with
Asphalt
(VFA), percent Dust -to-Binder Ratio(3) Minimum
Tensile
Strength
Ratio
(TSR)
AASHTO
T 283 Nominal Maximum Size Aggregate(2) Ninitial Ndesign Nmax 1 inch ¾ inch ½ inch ⅜ inch No. 4 sieve < 0.3 6 (≤91.5%) 50 (96.0%) 75 (≤98.0%) 12.0 13.0 14.0 15.0 − 70.0 to 80.0 0.8 to 1.6 0.80 0.3 to < 3 7 (≤90.5%) 75 (96.0%) 115 (≤98.0%) 65.0 to 78.0 3 to 30 8 (≤89.0%) 100 (96.0%) 160 (≤98.0%) 65.0 to 78.0 − 6 (≤91.5%) 50 (96.0%) 75 (≤98.0%) − − − − 16.0 76.0 to 80.0 0.6 to 2.0 (1)If mineral filler or hydrated lime is used, include in the calculation for compliance with the VMA. (2)The NMSA is one size greater than the first sieve to retain more than 10 percent of the combined aggregate. (3)Dust -to-binder ratio is the total percent of material passing the No. 200 sieve divided by the effective asphalt content . Dust includes lime, bag house fines, and other mineral matter. (4)Provide historical reference of satisfactory construction of mixtures submitted with VMA exceeding the minimum value by m ore tha n 3 percent, for approval. 309 (c)Antistrip additive. Use at least 1 percent Type 3 (lime) of the total weight of aggregates including RAP. Type 1 (liquid) antistrip additive may be used instead of Type 3 (lime) antistrip additiv e if the requirements shown in Table 401-2 are met. Table 401-2 Antistrip Requirements Using Hamburg Wheel -Track Testing, AASHTO T 324(1),(2)
PG Binder
Grade Testing
Temperature Maximum Allowable
Rut Depth Number of Passes Stripping Inflection
Point
PG 58 & lower 45 °C 12.5 mm 20,000 None Greater than PG 58 & less than PG 76 50 °C PG 76 & higher 55 °C (1)Report the plot of the rut depth versus number of passes for each test for each deformation location. Report the number of passes at maximum rut depth, the maximum rut depth, creep and strip slopes, the stripping inflection point, testing temperature, compaction method (slab or Superpave gyratory compactor cylindrical specimen), and air voidsof the specim ens. (2)Perform two tests at each additive rate and perform one set of control specimens with no additive. (d)Submittals . Submit written JMFs and associated material with Form FHWA 1641, Worksheet for Superpave Asphalt Concrete Mix Design , for verification at least 30 days before the control strip. Include a signed statement prepared by the testing laboratory that certifies the proposed JMF meetsrequirements and can be compacted in the field during production. For each proposed JMF, submitthe following: (1)Aggregate and mineral filler. (a)Target values: (1)Target value for percent passing each specified sieve size for the aggregate blend; and (2)Designate target values within the gradation band specified for the NMSA grading shown in Table 703-3. Allowable deviations are shown in Table 703-2 ; (b)Source and percentage of each stockpile to be used; (c)Average gradation of each stockpile; (d)Representative samples from each stockpile. Use split samples of material taken at the same time samples are taken for testing by the Contractor’s laboratory. (1)600 pounds of aggregates proportioned by each stockpile according to the JMF; (2)2 pounds of mineral filler, if proposed for the JMF; and (e)Results of aggregate quality tests performed within 1 year of use. (2)Asphalt binder. (a)Target asphalt binder content; (b)Five 1 -gallon samples of the asphalt binder; 310 (c)Test results fro m the manufacturer according to AASHTO M 320 for the asphalt binder including a temperature- viscosity curve; (d)Mixing temperature range and minimum compaction temperature for the asphalt binder; and (e)Laboratory mixing and compaction temperatures used for mix design. (3)Antistrip additives. If part of the JMF: (a)Type 1 (liquid) antistrip additive: (1)Target liquid antistrip additive dosage rate by weight of total binder; (2)Test results according to AASHTO T 324 and Table 401-2; (3)1 pint of liquid antistrip additive; (4)Name of product; (5)Manufacturer; and (6)Manufacturer’s SDS and product data sheets. (b)Type 3 (lime) antistrip additive: (1)1 pound of lime additive; (2)Name of product; (3)Manufacturer; (4)Manufacturer’s SDS and product data sheets; and (5)Dosage rate. (4)RAP. If part of the JMF: (a)Source and percentage of RAP; (b)Gradation of the RAP; (c)Effective specific gravities of each stockpile; (d)Percent asphalt binder in RAP by total mass according to AASHTO T 308; (e)100-p ound representative sample of each RAP stockpile; and (f)RAP data sheet of Form FHWA 1641.
(5)WMA technology and additive information.
(a)1-gallon WMA additive sample with method for incorporating it in the asphalt concrete mix design process;
(b)WMA manufacturer’s usage recommendations including additive target rates;
(c)Documentation of past WMA technology field applications including project type, project owner, tonnage placed, asphalt concrete mix design, mixture volumetrics, and performance;
(d)Laboratory mixing and compacting temperature;
(e)Asphalt binder performanc e grade test data over the range of WMA additive percentages proposed for use if applicable; (f) Compatibility of WMA additive with asphalt binder and antistrip additive; and
(g)Temperature range for field asphalt concrete mix production, delivery, lay- down and compaction.
(e)Verification. The verification process starts when required documentation and material are received. After the JMF is verified, start asphalt concrete mix production for the control strip.
(1)Aggregate gradations. The Contractor’s aggregate gradati on is verified if the CO’s gradation on the JMF design aggregate structure using the Contractor’s aggregate and RAP stockpile percentage recommendations is within the Contractor’s target value gradation plus or minus the tolerance shown in Table 401-3. Table 401-3 Aggregate Gradation Verification Tolerances
Sieve Size Tolerance,
percent (±) 1 in 3.0 ¾ in 3.0 ½ in 3.0 ⅜ in 3.0 No. 4 3.0 No. 8 3.0 No. 16 2.0 No. 30 2.0 No. 50 2.0 No. 200 1.0
(2)RAP asphalt binder content and gradation. The RAP asphalt binder content results are verified if the CO’s result for each stockpile is within ± 0.75 percent by total mass using AASHTO T 308. Submit the RAP dry gradation, burned gradation, asphalt content, and specific gravity information as shown on the RAP data sheet of Form FHWA 1641.
(3)Bulk specific gravity of aggregate (G sb). The coarse and fine G sb are verified if the CO’s results are within 0.013 for AASHTO T 85 and 0.030 for AASHTO T 84. 312 (4) VMA. The VMA result is verified if the CO’s result is above the specification limit in Table 401-1. Do not exceed 3 percent above the minimum VMA requirement without approval.
(5)VFA. The VFA result is verified if the CO’s result is within the specification limit in Table 401-1.
(6)Air voids (V a). The V a result is verified if the CO’s result at the same design asphalt binder content is between 3.0 and 5.0 percent.
(7)TSR. The TSR result is verified if the CO’s result meets the requirements shown in Table 401-1.
(f)Changes and resubmissions. If a JMF is rejected or the source of material is changed, submit a new JMF for verification. Allow up to 30 days for the CO to evaluate a change after receipt of required documentation and material. Approved changes in target values will not be applied retroactively for payment. The CO will deduct JMF evaluation costs resulting from the following:
(1)Contractor- requested changes to the approved JMF;
(2)Contractor requests for more than one JMF evaluation; and
(3)Additional testing necessary due to the failure of a submitted JMF.
401.04Mi xing Plant. Use mixing plants conforming to AASHTO M 156.
(a)Drum dryer- mixer plants.
(1)Bins. Provide a separate bin in the cold aggregate feeder for each individual aggregate stockpile in the asphalt concrete mix. Use bins of sufficient size to keep the plant in continuous operation and of proper design to prevent overflow of material from one bin to another.
(2)Stockpiling procedures. Separate aggregate into at least three stockpiles with different gradations.
(b)Batch plants.
(1)Hot aggregate bin. Provide a bin with three or more separate compartments for storage of the screened aggregate fractions to be combined for the asphalt concrete mix. Make the partitions between the compartments tight and of sufficient height to prevent spillage of aggregate from one compartment into another.
(2)Load cells. Calibrated load cells may be used in batch plants instead of scales.
(3)RAP. Modify batch plants so RAP is introduced into the asphalt concrete mix after bypassing the dryer. Design the cold feed bin, conveyor system, and special bin adjacent to the weigh hopper, if used, to avoid segregation and sticking of the recycled asphalt pavement material. Heat aggregate to a temperature that will transfer sufficient heat to the recycled asphalt pavement material to produce an asphalt concrete mix of uniform temperature within the range specified in the approved JMF.
(c)WMA plant modifications.
(1)Modify the mixing plant as required by the manufacturer to introduce the WMA technology. Interlock the WMA additive delivery system with the automated proportioning system.
(2)Incorporate additives and WMA technologies into the asphalt concrete mix according to the manufacturer’ s recommendations. Deliver and store of additives according to the manufacturer ’s recommendations.
(3)Modify the plant burner and drum flights to operate at lower production temperatures.
401.05Equipment.
(a)Pavers. Provide pavers that are:
(1)Self-contained, power -propelled units with adjustable vibratory screeds with full -width screw augers;
(2)Heated for the full width of the screed;
(3)Capable of spreading and finishing courses of asphalt concrete mix in widths at least 12 inches more than the width of one lane; (4) Equipped with a receiving hopper having sufficient capacity to ensure a uniform spreading operation; (5) Equipped with automatic feed controls, which are properly adjusted to maintain a uniform depth of material ahead of the screed;
(6)Operable at forward speeds consistent with satisfactory asphalt concrete mix lay down;
(7)Capable of producing a smooth- finished surface without segregating, tearing, shoving, or gouging; (8) Equipped with automatic screed controls with sensors that can sense grade from an outside reference line, sensing the transverse slope of the screed, and providing the automatic signals that operate the screed to maintain grade and transverse slope; and
(9)If required, provide a screed mounted safety edge device that can :
(a)Maintain contact with the road shoulder surface;
(b)Allow automatic transition to intersections and obstructions; and
(c)Constrain and reduc e the volume of the asphalt concrete material head to increase the density of the extruded profile. Do not use conventional single plate strike- off. 314 (b) Material transfer vehicle (MTV). If required, provide an MTV with the following:
(1)Independently operated with its own operator;
(2)Independent from the paver;
(3)A loading system with the ability to receive mixtures from the hauling equipment;
(4)A minimum storage capacity of 13 tons with a remixing system in the MTV storage bin;
(5)A discharge conveyor to deliver the mixture to the paver hopper; and
(6)A mass no more than the maximum legal loadings on structures. Pick-up machines, hopper inserts, and material transfer devices are not considered MTVs.
401.06Surface Preparation. Clean the existing surface of loose material, dirt, or other deleterious material by approved methods. Apply an asphalt tack coat to contact surfaces of pavements, curbs, gutters, manholes, and other structures according to Section 412.
401.07Weather Limitations. Place asphalt concrete mix on a dry, unfrozen surface when the air temperature in the shade is above 35 °F and rising. For HMA, conform to Table 401 -4. For WMA, adjust Table 401-4 minimum lay -down temperatures according to the manufacturer’s recommendations. Table 401-4 Asphalt Concrete Mix Placement Temperature
Compacted Lift
Thickness < 2 Inches 2 to 3 Inches > 3 Inches
Road Surface
Temperature, °F Minimum Lay -Down Temperature, °F(1) < 35 (2) (2) (2) 35 to 39.9 (2) (2) 280 40 to 49.9 (2) 285 275 50 to 59.9 295 280 270 60 to 69.9 285 275 265 70 to 79.9 280 270 265 80 to 89.9 270 265 260 ≥ 90 265 260 255
(1)Do not heat the asphalt concrete mix above the temperature specified in the approved asphalt concrete mix design.
(2)Do not pave.
401.08Asphalt Preparation. Uniformly heat the asphalt binder to provide a continuous supply of heated asphalt binder from storage to the mixer. Do not heat asphalt binder above 365 °F. If a liquid heat stable antistrip additive is used, meter it into the asphalt binder transfer lines at a bulk terminal or mixing plant. Inject the additive for at least 80 percent of the transfer or mixing time to obtain uniformity.
401.09Aggregate Preparation. If lime is used as an antistrip, adjust the aggregate moisture to at least 4 percent by mass of aggregate. Mix the lime uniformly with the aggregate before introducing the aggregate into the dryer or dryer drum. Use calibrated weighing or metering devices to measure the quantity of lime added to the aggregate. For batch plants, heat, dry, and deliver aggregate for pugmill mixing at a temperature sufficient to produce an asphalt concrete mix temperature within the approved range. Adjust flames used for drying and heating to prevent damage to and contamination of the aggregate. Additional plant adjustments may be required to provide dry aggregate at the reduced mixing temperatures of WMA. Control plant operations so the moisture content of the asphalt concrete mix behind the paver is no more than 0.5 percent according to AASHTO T 329. Before starting asphalt concrete mix production, obtain approval of synchronized metering and weighing devices used to introduce a constant rate of lime and water. Add lime to the aggregate by one of the following methods:
(a)Method A. Add lime to the combined cold feed aggregate using an enclosed in -line cold feed mechanical pugmill mixer. Use a twin -shaft, continuous m ixing pugmill with adjustable mixing paddles. Adjust the retention time of the mixture in the pugmill so no unmixed lime is visible after the lime and aggregate exit the pugmill.
(b)Method B. Add lime to the produced aggregates during stockpiling using a pugm ill. Distribute the lime according to the stockpile ratios stated in the asphalt concrete mix design. A minimum moisture content of 2 percent by dry weight for coarse aggregate and 4 percent by dry weight for fine aggregate is required at the time the aggr egates and lime are mixed. Marinate treated aggregate in stockpiles from 24 hours to 60 days before using in asphalt concrete mix. Do not use aggregate marinated longer than 60 days.
(c)Method C. Add lime to the combined cold feed aggregate as the aggregate f lows from the cold feed bins. Mix the lime and aggregate on the conveyor belt by placing at least six paddles over the conveyor belt. Make the paddles protrude into the aggregate flow and direct the aggregate to fold over itself causing the material to mig rate from one side of the conveyor belt to the other. Space the paddles to provide complete mixing. Provide a water spray over the conveyor belt as necessary to control dust and to maintain minimum moisture content.
401.10Mixing. Measure the aggregate an d asphalt into the mixer according to the JMF. Mix until particles are completely and uniformly coated with asphalt according to AASHTO M 156. Maintain the discharge temperature according to the JMF.
401.11Hauling. Use vehicles with clean and smooth metal beds free of holes for hauling asphalt concrete mixes. Coat the beds with an approved material to prevent the asphalt concrete mix from adhering to the beds. Do not use petroleum derivatives or other coating material that contaminates or alters the chara cteristics of the mix. Drain the bed before loading. 316 Equip each truck with a canvas cover or other suitable material of sufficient size to protect the asphalt concrete mix from the weather. If necessary to maintain temperature, use insulated truck beds and securely fastened covers. Provide access ports or holes for checking temperature of asphalt concrete mix in the truck.
401.12Production Start- Up Procedures. (a)Preparatory phase meeting. Conduct a pre -paving preparatory phase meeting according to Subsection 153.06(a) at least 3 days before the start of paving operations . Be prepared to discuss and provide the following: (1)Calibration certification for the gyratory compactor. If gyratory compactor is moved, recalibrate;(2)Asphalt and a ggregate correction factors according to AASHTO T 308 and AASHTO T 30 on Form FHWA 1640, Worksheet for Ig nition Furnace Binder Correction Factor AASHTO T 308. If RAP is included as part of the JMF, provide the asphalt and aggregate correction factors according to AASHTO T 30 and the FLH Addendum to AASHTO T 308 on Form FHWA 1648, WorksheetFor Ignition Furnace Binder Correction Factor And Aggregate Gradation Correction Factor ForMixes Including RAP ; and (3)Plant mixing temperature. (b)Control strip. Provide at least 7 days’ notice before starting production of an asphalt concrete mix. Produce sufficient asphalt concrete mix to construct a 1000- foot-long control strip, one -lane wide, and at the designated lift thickness. Construct the control strip on the project at an approved location. Construct the control strip using asphalt concrete mix production, lay- down, and compaction procedures intended for the entire mix. Construct a control strip for each equipment combination and each plant from which production is intended. Stop production after construction of the control strip until the asphalt concrete mix and the control strip are accepted. Acceptance will be based on the following: (1)Mixture. Take at least three control strip asphalt concrete mix sample s and test samples as shown in Table 401 -10. The asphalt concrete mix is acceptable if all test results are within specification limits for asphalt content, VMA, and VFA; and the calculated pay factor for asphaltcontent, VMA, VFA, and gradation is 0.90 or greater. (2)Compaction. Compact according to Subsection 401.14. Take nuclear gauge density readings behind each roller pass to determine the roller pattern necessary to achieve required density. Use Form FHWA 1646, Asphalt Control Strip Worksheet . Document if roller wa s operated in vibratory or static mode. Provide frequency and amplitude settings if operated in vibratory mode. Providedocumentation after completion of the control strip. Take nuclear gauge density readings and cut and test core samples as shown in Table 401-10. Density is acceptable if the core density pay factor is 0.90 or greater. Provide the CO with documented nuclear gauge readings correlated to core specific gravities. 317 (3)Control strip mat defects. Control strips that exhibit physical or visual defects may be rejected. Defects include tearing, cracking, rutting, shoving, segregation, bleeding, excessive pavement roughness, and poor joints. Repeat the control strip process until an acceptable control strip is produced. Conform to Subsection 106.01 for the disposition of material in rejected control strips. Accepted control strips may remain in place and will be accepted and measured as a part of the completed pavement. Tests used for the control strip will not be included in the evaluation for payment according to Subsection 106.05. Start full production only after the control strip is verified and accepted. Use start -up procedures if resuming production after a te rmination of production due to unsatisfactory quality according to Subsection 106.05.
401.13Placing and Finishing. Do not use mixes produced from different plants unless the mixes are produced according to the same JMF, use material from the same sources, and are approved. Place HMA and WMA at temperatures according to Subsection 401.07 . Measure temperature of the asphalt concrete mix in the hauling vehicle immediately before dumping into the spreader or measure it in the windrow immediately before pickup. Suspend paving if the MTV malfunctions during paving operations. Do not resume mix placement until the MTV is operational. Do not use diesel fuel or products that cause stripping as a release agent on equipment used with the asphalt concrete mix. Place the asphalt concrete mix as continuously as possible. Control horizontal alignment usi ng a reference line. Automatically control the grade and slope from reference lines, a ski and slope control device, or dual skis. Use skis having a length of at least 20 feet. In areas where mechanical spreading and finishing are impractical, place and fi nish the asphalt concrete mix with alternate equipment to produce a uniform surface closely matching the surface obtained when using a mechanical paver. Offset the longitudinal joint of one lift at least 6 inches from the joint in the lift immediately belo w. Make the longitudinal joint in the top lift along the striped centerline of two -lane roadways or at the lane lines of roadways with more than two lanes.
401.14Compacting. Provide at least three rollers, with at least one being a pne umatic -tire roller with rubber tires in the front and rear. Provide one roller each for breakdown, intermediate, and finish rolling. Size the rollers to achieve the required results. Operate rollers according to the manufacturer’s recommendations. Do not cause cracking, shoving, or undue displacement. Do not pass rollers over an unsupported edge of freshly laid asphalt concrete mix. Continue rolling until roller marks are eliminated, cracks are sealed, and the required density is obtained. For HMA, do not roll the mix after the surface cools below 175 °F. Monitor the compaction process with nuclear density gauges calibrated to the control strip core density test results and evaluate according to Subsection 401.18(c) . 318 Take nuclear gauge density readings and cut and test core samples as shown in Table 401-10. Compact the asphalt concrete mix with alternate equipment to obtain the required compaction along forms, curbs, headers, walls, and other places inaccessible to rollers.
401.15Joints, Trimming Edges, and Cleanup. Complete pavement construction of adjacent traffic lanes to the same elevation within 24 hours. If elevation differences more than 3 inches between adjacent lanes are left overnight, sig n with " Uneven Lanes " warning signs and provide a 1V:3H fillet. Make transverse joints vertical to the depth of the new pavement at connections to existing pavements and previously placed lifts. Form vertical and clean transverse joints by cutting back the previous run to expose the full -depth course. Protect saw cut edge from equipment and traffic. Repair damaged joints by sawcutting before placement of adjoining asphalt concrete pavement. Apply an asphalt tack coat to the edge of both transverse and longi tudinal joints according to Section 412. Dispose of material trimmed from the edges and other discarded asphalt concrete mix according to Subsection 203.07.
401.16Pavement Roughness. Measu re the profile of the pavement surface according to the designated pavement roughness type. If no roughness type is designated, use Type IV. In addition, construct pavement surfaces to meet the requirements of Subsection 401.16(d) . Provide flaggers, pilot car operations, or other temporary traffic control during profile measurement according to Section 635. (a)Profile measurement. The CO will use profile measurements to determine the Mean Roughness Index (MRI) values for the traveled way according to FLH T 401 and using the current version ofProfile Viewer and Analysis (ProVAL) software. The CO will determine areas of localized roughness.The MRI and areas of localized roughness will be used to determine payment for the designatedpavement roughness type and pavement areas requiring surface corrections. The CO will identify the starting and ending points of the profile measurements. The CO will identify excluded areas. Cattle guards, bridges not being overlaid, and turning lanes, passing lanes, side roads, and ramps less than 1000 feet in length will be excluded from profile measurement, the calculation of MRI, and the determination of localized roughness. Measure excluded areas with a strai ghtedge according to Subsection 401.16(d) . Areas for which the ProVAL continuous report exceeds the threshold MRI value for the specified roughness type will be considered a defective area requiring correction. If corrections ar e not allowed, a reduction in payment will be applied according to Subsection 401.20(b). No deduction will be made for areas of localized roughness identified within 12.5 feet of the starting or end of a profile section or within 12.5 feet of excluded areas. Measure these areas with a straightedge according to Subsection 401.16(d) . (b)Type I and II pavement roughness. Measure the profile of the initial pavement surface before construction activities distu rb the existing pavement surface. The initial pavement surface is defined as the existing pavement surface before construction activities start. 319 Do not proceed with work that will disturb the initial pavement surface until the CO’s analysis is complete. Measure the profile of the final pavement surface before placing a surface treatment and within 21 days of completing roadway paving. The original overall surface MRI will be used in conjunction with the final overall MRI to determine an overall percent improvement for the entire traveled way. (c)Type III pavement roughness. Measure the profile of the final pavement surface before placing a surface treatment and within 21 days of completing roadway paving. (d)Type IV straightedge measurement. Measure the pavement surface using a 10- foot metal straightedge at right angles and parallel to the centerline. Defective areas are deviations between thesurface and the bottom of the straightedge more than ¼ inch measured between two contacts of thestraightedge or deviations more than ¼ inch measured at the end of the straightedge.
401.17Defective Area Correction. Obtain approval before starting corrective work. Allow 7 days for review and approval of correction method proposal. Do not correct defective areas on the final pavement surface unless approved. Evaluate and correct defective areas, including localized roughness, on lower lifts by one of the following: (a)Milling. Replace the defective area by milling at least one- half of the pavement depth and repaving with the approved asphalt concrete mix. Extend defective area corrections beyond the wheel path. Millthe defective area according to Section 413.
(b)Sawcutting. Replace the defective area by sawcutting and removing the defective area and repaving with the approved asphalt concrete mix. Saw cut and remove the defective area according toSection 203. Extend defective area corrections beyond the wheel path. (c)Grinding. Use a diamond blade machine to grind off the defective surface area. Submit the manufacturer and model of the equipment to be used. Identify the starting and ending station of eachgrind location, the grinding depth, and lateral extent of grinding. Optimize the endpoints of the areaswhere a grinder is to be applied using ProVAL’s Smoothness Assurance function in conjunction with the grinding simulation function. Submit the type of seal to be placed after grinding is comple ted for approval. Place seals according to Section 409 or 410. Limit the grinding depth to 12.5 percent of the design pavement thickness. If grinding more than this depth, provide a minimu m 1-inch overlay. (d)Other. Submit a proposal for approval for other correction methods not listed above. After corrections are made, re- measure the pavement profile according to Subsection 401.16(a ). Data from the re -measurement will be analyzed to determine the MRI or percent improvement, areas of localized roughness, and the final PF rough. If correction and re -measurement of the surface is required, the maximum allowable pay factor under Subsection 401.20 is 1.00. If corrections are not allowed, no adjustment will be made to the final PF rough or localized roughness pay deductions.
401.18Acceptance. See Table 401- 10 for sampling, testing, and acceptance requirements. Aggregate quality properties will be evaluated under Subsections 106.02 and 106.04. 320 Mineral filler, antistrip additives, and WMA additive s will be evaluated under Subsections 106.02 and 106.03. Asphalt content, VMA, and core density will be evaluated under Subsection 106.05. Pavement roughness will be evaluated under Subsection 106.04. Asphalt binder will be evaluated under Subsections 106.03 and 106.04. Evaluations will consider the following: (a)Asphalt content. The upper and lower specification limits are the approved JMF target value ±0.4 percent; (b)VMA. The lower specification limits are shown in Table 401 -1. Use the Contractor’s combined coarse and fine bulk specific gravity of aggregate G sb values to calculate VMA on field produced asphalt concrete mix samples;(c)Density (core). The lower specification limit is 91.0 percent of the maximum specific gravity (density) determined according to AASHTO T 166 and AASHTO T 209.The percent compaction will be determined using the average maximum specific gravity (AASHTO T 209) from all samples tested the day the core was obtained; (d)Pavement roughness. The evaluation for p ayment will be made after defective areas are addressed. The pay factor is determined from Table 401-6, Table 401-7, Table 401-8, and Table 401-9; and(e)Asphalt binder. The pay factor is determined from Table 401-5. Construction of the HMA or WMA pavement course will be evaluated under Subsections 106.02 and 106.04. Asphalt tack coat will be evaluated under Section 412.
Measurement
401.19Measure the Section 401 pay items listed in the bid schedule according to Subsection 109.02 .
Payment
401.20The accepted quantities will be paid at the contract price per unit of measurement for the Section 401 pay items listed in the bid schedule, except the asphalt concrete pavement contract price will be adjusted according to Subsections 106.05, 401.18(d) and (e). Payment w ill be full compensation for the work prescribed in this Section. See Subsection 109.05. Payment will be adjusted according to the following: (a)Asphalt concrete pavement. Payment for asphalt concrete pavement will be made at a price determined by multiplying the contract price by the material pay factor for each lot. The material pay factor is calculated as follows: PFmaterial = 1 + [(PF Volumetric – 1) + (PF PG – 1)] where: PFmaterial = Material pay factor. PFVolumetric = Pay factor for asphalt concrete pavement. PF Volumetric is the lowest single pay factor determined for asphalt binder content, VMA, and core density. PFPG = Pay factor for asphalt binder. The PF PG formula is as follows: 𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃 =(𝑃𝑃𝑃𝑃1 + 𝑃𝑃𝑃𝑃2 + 𝑃𝑃𝑃𝑃3 + … .𝑃𝑃𝑃𝑃𝑛𝑛) 𝑛𝑛 where: PF# = For each sample, the lowest pay factor determined from any test in Table 401-5. If the lowest pay factor for a sample is in reject, the sample’s pay factor is zero. n = Number of samples tested. If either the pay factor for the asphalt binder (PF PG) or the pay factor for asphalt concrete pavement (PF Volumetric ) is below 0.75, the lot for asphalt concrete pavement is in reject.
(b)Pavement roughness. If the contract specifies a pavement roughness Type I, Type II, or Type III, a separate pay adjustment will be made for pavement roughness calculated as follows: Type I, Type II, or Type III Pay Adjustment = (RF)(PF rough - 1.00)(L) – (LRPR) where: PFrough = Pay factor from Tables 401-6, 401-7, or 401-8. L = Total project length in lane miles. LRPR = Localized roughness pay reduction. Each area of localized roughness more than the localized roughness threshold MRI specified for the designated pavement roughness type will receive a reduction in payment according to Table 401-9. RF = Roughness factor: 100,000. For Type I and Type II pavement roughness, the localized roughness threshold computed to the nearest whole number is equal to the following: Type I Localized Roughness Threshold = Initial Overall MRI + 1.881(S 25) Type II Localized Roughness Threshold = Initial Overall MRI + 1.282(S 25) where: Initial Overall MRI = MRI obtained before construction activities start. S25 = sample standard deviation of the 25- foot fixed interval MRI values. 322 The overall percent improvement in MRI will be determined to one decimal place for the traveled way according to the following formula: 𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑛𝑛𝑓𝑓 𝐼𝐼𝐼𝐼𝐼𝐼𝑃𝑃𝑇𝑇𝐼𝐼𝑃𝑃𝐼𝐼𝑃𝑃𝑛𝑛𝑓𝑓 = �(𝐼𝐼𝑛𝑛𝐼𝐼𝑓𝑓𝐼𝐼𝐼𝐼𝐼𝐼 𝑂𝑂𝐼𝐼𝑃𝑃𝑃𝑃𝐼𝐼𝐼𝐼𝐼𝐼 𝑀𝑀𝑅𝑅𝐼𝐼 – 𝑃𝑃𝐼𝐼𝑛𝑛𝐼𝐼𝐼𝐼 𝑂𝑂𝐼𝐼𝑃𝑃𝑃𝑃𝐼𝐼𝐼𝐼𝐼𝐼 𝑀𝑀𝑅𝑅𝐼𝐼 ) 𝐼𝐼𝑛𝑛𝐼𝐼𝑓𝑓𝐼𝐼𝐼𝐼𝐼𝐼 𝑂𝑂𝐼𝐼𝑃𝑃𝑃𝑃𝐼𝐼𝐼𝐼𝐼𝐼 𝑀𝑀𝑅𝑅𝐼𝐼�× 100 For Type I pavement roughness, Table 401-6 will be used to determine the fina l pay factor (PF rough) for the traveled way to two decimal places. If the percent improvement is less than 25.0 percent and the final overall MRI value is less than or equal to 70.0 inches per mile, Type III -A from Table 401 -8 will be used to determine the final PF rough. For Type II pavement roughness, Table 401 -7 will be used to determine the final PF rough for the traveled way to two decimal places. If the percent improvement is less than 49.0 percent and the final overall MRI value is less than or equal to 70.0 inches per mile, Type III -A from Table 401-8 will be used to determine the final PF rough. For Type III pavement roughness, pay factors from Table 401-8 will be used in conjunction with the long continuous histogram printout from ProVAL’s Smoothness Assurance Analysis function and by utilizing a long continuous 528- foot segment length for analysis. The localized roughness threshold for Type III pavement roughness is 140 inches per mile. The final PF rough is equal to the sum of the products of the individual pay factors shown in Table 401 -8 multiplied by the ratio of individual lane miles to the overall project lane mile s and by ProVAL’s corresponding histogram percentages, divided by 100. The final PF rough will be determined to three decimal places. For Type IV pavement roughness, each defective area as determined by a 10- foot metal straightedge will receive a reduction in payment according to Table 401-9. Table 401-5
Asphalt Binder Pay Factor Table
Property Specifications(1) Pay Factor 1.01 1.00 0.95 0.90 0.75 Reject
Tests on Original
Dynamic shear
rheometer, kPa ≥ 1.00 ≥ 1.17 1.16 to 1.00 0.99 to 0.89 0.88 to 0.77 0.76 to 0.50 < 0.50 Tests after Rolling Thin Film Oven (RTFO)
Dynamic shear
rheometer, kPa ≥ 2.20 ≥ 2.69 2.68 to 2.20 2.19 to 1.96 1.95 to 1.43 1.42 to 1.10 < 1.10 Tests on Pressure Aging Vessel (PAV)
Dynamic shear
rheometer, kPa(2) < 5000 ≤ 4711 4712 to 5000 5001 to 5289 5290 to 5578 5579 to 6000 > 6000
Bending beam
rheometer, s, MPa ≤ 300 ≤ 247 248 to 300 301 to 338 339 to 388 389 to 449 ≥ 450
Bending beam
rheometer, m -value ≥ 0.300 ≥ 0.320 0.319 to 0.300 0.299 to 0.294 0.293 to 0.278 0.277 to 0.261 < 0.261 (1)Conform to Subsection 702.01. (2)If dynamic shear rheometer (PAV) value is between 5000 kPa and 6000 kPa, and the phase angle is equal to or greater than 42 degrees , the pay factor is 1.00 Table 401-6
Type I Pavement Roughness Pay Factors
Type I -A Type I -B – Percent Improvement (%) Percent Improvement (%) Pay Factor (PFrough) Greater than 50.0 Greater than 45.0 1.05 47.6 to 50.0 44.0 to 45.0 1.04 45.1 to 47.5 43.0 to 43.9 1.03 43.6 to 45.0 41.6 to 42.9 1.02 42.1 to 43.5 40.1 to 41.5 1.01 25.0 to 42.0 20.0 to 40.0 1.00 24.0 to 24.9 19.0 to 19.9 0.99 23.0 to 23.9 18.0 to 18.9 0.98 22.0 to 22.9 17.0 to 17.9 0.97 21.0 to 21.9 16.0 to 16.9 0.96 20.0 to 20.9 15.0 to 15.9 0.95 19.0 to 19.9 14.0 to 14.9 0.94 18.0 to 18.9 13.0 to 13.9 0.93 17.0 to 17.9 12.0 to 12.9 0.92 16.0 to 16.9 11.0 to 11.9 0.91 15.0 to 15.9 10.0 to 10.9 0.90 14.0 to 14.9 9.0 to 9.9 0.89 13.0 to 13.9 8.0 to 8.9 0.88 12.0 to 12.9 7.0 to 7.9 0.87 11.0 to 11.9 6.0 to 6.9 0.86 10.0 to 10.9 5.0 to 5.9 0.85 5.0 to 9.9 4.0 to 4.9 0.80 0.0 to 4.9 0.0 to 3.9 0.70 Negative Improvement Negative Improvement Correct & overlay Table 401-7
Type II Pavement Roughness Pay Factors
Type II -A Type II -B – Percent Improvement (%) Percent Improvement (%) Pay Factor (PFrough) Greater than 60.0 Greater than 50.0 1.05 58.6 to 60.0 49.0 to 50.0 1.04 57.6 to 58.5 48.0 to 48.9 1.03 56.6 to 57.5 47.0 to 47.9 1.02 55.1 to 56.5 45.0 to 46.9 1.01 49.0 to 55.0 35.0 to 44.9 1.00 48.0 to 48.9 34.0 to 34.9 0.99 47.0 to 47.9 33.0 to 33.9 0.98 46.0 to 46.9 32.0 to 32.9 0.97 45.0 to 45.9 31.0 to 31.9 0.96 44.0 to 44.9 30.0 to 30.9 0.95 43.0 to 43.9 29.0 to 29.9 0.94 42.0 to 42.9 28.0 to 28.9 0.93 41.0 to 41.9 27.0 to 27.9 0.92 40.0 to 40.9 26.0 to 26.9 0.91 38.0 to 39.9 25.0 to 25.9 0.90 36.0 to 37.9 24.0 to 24.9 0.89 35.0 to 35.9 23.0 to 23.9 0.88 34.0 to 34.9 22.0 to 22.9 0.87 33.0 to 33.9 21.0 to 21.9 0.86 31.0 to 32.9 20.0 to 20.9 0.85 25.0 to 30.9 16.0 to 19.9 0.80 10.0 to 24.9 7.5 to 15.9 0.70 Less than 10.0 Less than 7.5 Correct & overlay Table 401-8
Type III Pavement Roughness Pay Factors
Type III -A, inch/mile Type III -B, inch/mile Pay Factor (PF rough) Mean Roughness Index (MRI) Mean Roughness Index (MRI)
If MRI of entire roadway is
greater than 125 in/mi If MRI of entire roadway is greater than 135 in/mi REJECT Greater than 95.0 Greater than 110.0 0.700 95.0 to 90.0 110.0 to 105.0 0.800 90.0 to 85.0 105.0 to 100.0 0.850 85.0 to 80.0 100.0 to 95.0 0.900 80.0 to 75.0 95.0 to 90.0 0.960 75.0 to 70.0 90.0 to 85.0 0.980 70.0 to 65.0 85.0 to 80.0 1.000 65.0 to 60.0 80.0 to 75.0 1.010 60.0 to 55.0 75.0 to 70.0 1.020 55.0 to 50.0 70.0 to 65.0 1.025 50.0 to 45.0 65.0 to 60.0 1.030 45.0 to 40.0 60.0 to 55.0 1.035 40.0 to 35.0 55.0 to 50.0 1.040 35.0 to 30.0 50.0 to 45.0 1.045 Less than 30.0 Less than 45.0 1.050 Table 401-9 Localized Roughness and Straightedge Measurement Pay Reductions
Type I Type II & IV
Localized
Roughness Limit
MRI Type III
Deduction
per
Occurrence Deduction
per
Occurrence Localized
Roughness
Limit
MRI, inch/mile Deduction per
Occurrence
$200 $300 Computed MRI value according to Subsection:
401.16(b) for Type I 401.16(b) for Type II 401.16(c) for Type III 140.0 to 169.9 $300 170.0 to 179.9 $450 180.0 to 189.9 $600 190.0 to 199.9 $750 200.0 to 209.9 $900 210.0 to 219.9 $1,200 220.0 to 229.9 $1,500 230.0 to 239.9 $2,000 > 240.0 $4,000 Table 401-10 Sampling, Testing, and Acceptance Requirements
Material or
Product
(Subsection) Type of
Acceptance
(Subsection) Characteristic Category Test Methods
Specifications Sampling
Frequency Point of
Sampling Split
Sample Reporting
Time Remarks
Source
Asphalt
concrete aggregate (703.07 ) Measured & tested for conformance (106.04 & 105) Aggregate quality − Subsection
703.071 per type & source of material Source of material Yes Before production Not required if using
Government-
furnished source
Asphalt binder
(702.01) Measured & tested for conformance (106.04 & 105) Quality − AASHTO M 320 1 per type & source of material Asphalt supplier or mixing plant Yes Before production −
Asphalt
concrete aggregate (703.07 ) Process control (153.03 ) Gradation − AASHTO T 27 & T 11 2 per day per stockpile Crusher belt (during production) No 24 hours Not required if using a pre -crushed commercial source Table 401- 10 (continued) Sampling, Testing, and Acceptance Requirements
Material or
Product
(Subsection) Type of
Acceptance
(Subsection) Characteristic Category Test Methods
Specifications Sampling
Frequency Point of
Sampling Split
Sample Reporting
Time Remarks
Mix Design
Asphalt
concrete mixture Measured & tested for conformance (106.04 ) Gradation − AASHTO T 27 & T 11 1 per submitted mix design Stockpiles Yes 30 days before producing −
RAP asphalt
binder content − AASHTO T 308 " " " " −
Bulk specific
gravity of aggregate (coarse & fine) − AASHTO T 84 & T 85 " " " " − VMA − AASHTO R 35 " − " " − VFA − " " − " " − Air voids − " " − " " −
Tensile strength
ratio − AASHTO T 283 " − " " − Table 401- 10 (continued) Sampling, Testing, and Acceptance Requirements
Material or
Product
(Subsection) Type of
Acceptance
(Subsection) Characteristic Category Test Methods
Specifications Sampling
Frequency Point of
Sampling Split
Sample Reporting
Time Remarks
Production Start -up (control strip)
Asphalt
concrete pavement Statistical (106.05 ) Gradation
AASHTO
T 30 3 minimum Behind the paver before compaction Yes 6 hours − No. 4 I No. 30 I No. 200 I
Other specified
sieves II
Asphalt
content(1) I AASHTO T 308 " " " " −
VMA I AASHTO
R 35 " " " " − VFA II " " " " " − Density(2) I AASHTO T 166 5 minimum
In-place
after compaction " 24 hours Deliver cores to CO after testing is completed Table 401- 10 (continued) Sampling, Testing, and Acceptance Requirements
Material or
Product
(Subsection) Type of
Acceptance
(Subsection) Characteristic Category Test Methods
Specifications Sampling
Frequency Point of
Sampling Split
Sample Reporting
Time Remarks
Production Start -up (control strip) (continued)
Asphalt
concrete pavement Measured & tested for conformance (106.04 ) Mix temperature − − First load & as directed thereafter Hauling vehicle before dumping or windrow before pickup No Immediately upon completion of test −
Maximum
specific gravity(4) − AASHTO T 209 3 minimum Behind the paver before compaction Yes 24 hours −
Process
control (153.03 ) Density − ASTM D2950 5 minimum At core location before coring No 24 hours See
Subsection
401.12 Table 401- 10 (continued) Sampling, Testing, and Acceptance Requirements
Material or
Product
(Subsection) Type of
Acceptance
(Subsection) Characteristic Category Test Methods
Specifications Sampling
Frequency Point of
Sampling Split
Sample Reporting
Time Remarks
Production
Asphalt
concrete pavement Statistical (106.05 ) Asphalt content(1) I AASHTO T 308 1 per 700 tons
Behind the
paver before compaction Yes 6 hours −
VMA I AASHTO
R 35 " " " " − Density(2) I AASHTO T 166 " In-place after compacting " 24 hours Deliver cores to CO after testing is completed
Measured
& tested for conformance (106.04 ) Placement temperature − − First load & as determined by the CO thereafter Hauling vehicle before dumping, or windrow before pickup No Immediately upon completion of measurement −
Maximum
specific gravity(3),(4) − AASHTO T 209 1 per day minimum Behind the paver before compaction Yes 24 hours −
Asphalt
binder (702.01 ) Measured & tested for conformance (106.04) Quality See Table 401-5 AASHTO M 320 1 per 2000 tons of mix In line between tank and mixing plant Yes, 2 1-quart samples − Tested by the
Government
Table 401- 10 (continued) Sampling, Testing, and Acceptance Requirements
Material or
Product
(Subsection) Type of
Acceptance
(Subsection) Characteristic Category Test Methods
Specifications Sampling
Frequency Point of
Sampling Split
Sample Reporting
Time Remarks
Production (continued)
Asphalt
concrete pavement Process control (153.03 ) Gradation at plant − AASHTO T 27 & T 11 Contractor determined Cold feed or hot bins as applicable No 24 hours −
Moisture
content of aggregates − AASHTO T 255 Contractor determined Stockpile " " −
Gradation
at paver − AASHTO T 30 1 per 700 tons of mix Behind the paver before compaction " " − Air voids − AASHTO T 312 & T 166 " " " " − VFA − AASHTO R 35 " " " " − Density − ASTM D2950 1 per 500 ft In-place after compacting " " − Table 401- 10 (continued) Sampling, Testing, and Acceptance Requirements
Material or
Product
(Subsection) Type of
Acceptance
(Subsection) Characteristic Category Test Methods
Specifications Sampling
Frequency Point of
Sampling Split
Sample Reporting
Time Remarks
Finished Product
Asphalt
concrete pavement Measured & tested for conformance (106.04 ) Type I & II roughness, before construction (Initial MRI) − FLH T 401 See
Subsection
401.16Left and right wheel paths No Within 21days before ground disturbing work Original surface before construction
Type I, II & III
roughness, after construction (Final MRI) − " " " " Within 21 days after completing paving −
Process
control (153.03 ) Surface tolerance − Straightedge measurements
Subsection
401.16(d) Contractor determined See
Subsection
401.16(d) " 24 hours −
(1)Use AASHTO T 308, Method A. Calculate the asphalt binder content by weighing the sample before and after the burn using a calibrated external balance.
(2)Cut two 6 -inch diameter side by side cores. Obtain cores according to AASHTO R 67 as soon as the pavement has cooled sufficiently to allow coring, but not later than 12 hours after final rolling. Remove them with a core retriever and fill and compact the core holes with asphalt concrete mixture. Label the cores and protect them from damage due to handling and temperature. Submit one core for verification testi ng. Dry the other core to constant mass at 125±5 °F or vacuum dry it according to ASTM D7227 before performing the core density and measuring the thickness according to ASTM D3549. Use 62.245 pounds per cubic foot to convert specific gravity to density.
(3)After production paving has begun, use the average maximum specific gravity value (AASHTO T 209) for each day to adjust t he perce nt compaction for the cores that represent that day’s paving.
(4)Do not use the supplemental procedure for mixtures containing porous aggregate (dry back method of AASHTO T 209).