401HOT MIX ASPHALT PAVEMENT

121 ALASKA 2020 DIVISION 400 –ASPHAL T PAVEMENTS AND SURFACE TREATMENTS HOT MIX ASPHALT PAVEMENT

401-1.01DESCRIPTION . Construct one or more courses of plant -produced Hot Mix Asphalt

MATERIALS

401-2.01ASPHALT BI NDER . Conform to Subsection 702- 2.01. Asphalt binder may be

conditionally accepted at the source providing a manufacturers certificati on of compliance according to Subsection 106- 1.05, and test results of the applicable requirements of Section 702. Use PG 52 -28 if no Grade is specified.

401-2.02LIQUID ANT I-STRIP ADDITIVE. Use anti -strip agents in the proportions determined

by ATM 414 and included in the approved Job Mix Design (JMD). At least 90 percent of the aggregate must remain coated when tested according to ATM 414. The following minimum dose

401-2.03JOINT ADHE SIVE. Conform to Subsection 702- 2.05

401-2.04JOINT SEAL ANT. Conform to Subsection 702- 2.06

401-2.05WARM MIX ASPHALT . Conform to Subsection 702- 2.07

401-2.06ASPHALT RE LEASE AGENT . Conform to Subsection 702- 2.08

401-2.07AGGREGATES . Conform to Subsection 703- 2.04. Use a minimum of three stockpiles

of crushed aggregate (coarse, intermediate, and fine). Place blend material, if any, in a fourth pile.

401-2.08RECYCLED A SPHALT PAVEMENT . Recycled asphalt pavement (RAP) may be used

in the production of HMA. The RAP may be from pavements removed under the Contract, or from an existing stockpile. Conform to Subsection 703 -2.16.

401-2.09JOB MIX DES IGN. Provide target values for gradation that satisfy both the broad band

gradation limits shown in Table 703- 4 and the requirements of Table 401- 1, for the Type and Class of HMA specified. TABLE 401 -1 HMA MARSHALL DESIGN REQUIREMENTS DESIGN PARAMETER CLASS “A” CLASS “B” HMA (Including Asphalt Binder) Stability, Pounds 1800 Min. 1200 Min. Flow, 0.01 Inch 8 – 14 8 - 16 Voids in Total Mix (VTM), % 3.0 – 5.0 3.0 – 5.0 Compaction, Number of Blows Ea ch Side of 75 50 Liquid Anti -strip Type Minimum Dose by Weight of Asphalt Binder, % Amines based 0.30 Phosphate Ester based 0.30 Organo -Silane based 0.05 122 ALASKA 2020 DESIGN PARAMETER CLASS “A” CLASS “B” Test Specimen Asphalt Binder Voids Filled with Asphalt (VFA), % 65 - 75 65 - 78 Asphalt Content, Min. % 5.0 5.0 Dust-Asphalt Ratio* 0.6 - 1.4 0.6 - 1.4 Voids in the Mineral Aggregate (VMA), %, Min. Type I 12.0 11.0 Type II 13.0 12.0 Type III, IV 14.0 13.0 Liquid Anti -Strip Additive**,%, Min. 0.30 0.30 RAP, %, Max. 15.0 25.0 *Dust -Asphalt ratio is the percent of material passing the No. 200 sieve divided by the percent of effective asphalt binder (calculated by weight). ** By Weight of Asphalt Binder The approved JMD will specify the Target Values (TV) for gradation, the TV for asphalt binder content, the Maximum Specific Gravity (MSG) of the HMA, the additives, and the recommended mixing temperature range. Submit the followi ng to the Engineer at least 15 days before the production of HMA:

JMD, gradations for individual stockpiles, and the blend ratio of each aggregate stockpile.

mineral filler, if any) in the proposed mix design. Furnish a total of 500 po unds of material in the proportional amounts in the proposed JMD.

name of product, manufacturer, test results of the applicable quality requirements of Subsection 702- 2.01, manufacturer's certificate of compliance according to Subsection 106- 1.05, a temperature- viscosity curve for the asphalt binder or manufacturer's recommended mixing and compaction temperatures, and current Material Safety Data Sheet.

product, manufacturer, and manufacturer's data sheet, and current Material Safety Data Sheet.

where additive will be introduced and manufacturer’s recommended usage rate for each type of HMA. Supply a minimum of 2- pint samples for each proposed additive.

200-pound sample of proposed RAP. The Engineer will evaluate the material and the proposed gradation using ATM 417 and the requirements of Table 401- 1 for the appropriate Ty pe and Class of HMA specified, and establish the approved JMD which will become a part of the Contract. Anti-strip evaluation (ATM 414) of HMA mix designs that include RAP will be completed without the inclusion of the RAP. 123 ALASKA 2020 Obtain an approved JMD prior to shipment of aggregates to an asphalt plant site or producing HMA for payment.

approves a request from the Contractor to perform the JMD at no cost to the Department , provide a JMD following the requirements specified in this section. Submit the JMD to the Engineer at least 15 working days before HMA production. Submit samples to the Engineer upon request for JMD verification testing. All Contractor -furnished JMDs m ust be sealed by a professional Engineer registered in the State of Alaska. The Professional Engineer shall certify that the JMD was performed according to the specified procedures, and meets all project specifications.

the original JMD submittal when:

Table 401- 1

Changes to the JMD apply only to HMA produced after the approval of changes. CONSTRUCTION REQUIREMENTS

401-3.01PRE -PAVING MEETING. Meet with the Engineer for a pre- paving meeting in the

presence of project superintendent and paving foreman at least five (5) working days before beginning paving operations. Submit a paving plan and pavement inspection plan (per 401- 3.20) at the meeting. Include the following elements in the paving plan and address these elements at the meeting:

and compaction

tolerance requirements

binder content, and density, and

meets the contract requirements 124 ALASKA 2020 Include the following elements in t he pavement inspection plan and address these elements at the meeting:

401-3.02CONTRACTOR QUALITY CONTROL . Perform quality control (QC) of HMA materials

in accordance with Subsection 106- 1.03.

401-3.03WEATHER LI MITATIONS . Place HMA on a stable/non- yielding roadbed. Do not place

HMA when the base material is wet or frozen, or when weather conditions prevent proper handling or finishing of the mix. Do not place H MA leveling course when the roadway surface temperature is colder than 40° F.

401-3.04EQUIPMENT, GENERAL . Use equipment in good working order and free of HMA

buildup. Make all equipment available for inspection and demonstration of operation a minimum of 24 hours before placement of HMA.

401-3.05ASPHALT MI XING PLANT . Meet AASHTO M 156. Use an HMA plant capable of

producing at least 150 tons of HMA per hour noted on posted DEC air quality permit, designed to dry aggregates, maintain consistent and acc urate temperature control, and accurately proportion asphalt binder and aggregates. Calibrate the HMA plant and furnish copies of the calibration data to the Engineer at least 24 hours before HMA production. Provide a scalping screen at the asphalt plant to prevent oversize material or debris from being incorporated into the HMA. Provide a tap on the asphalt binder supply line just before it enters the plant (after the 3- way valve) for sampling asphalt binder. Provide aggregate and asphalt binder sampli ng locations meeting OSHA safety requirements. You may use belt conveyor scales to proportion plant blends and mixtures if the scales meet the general requirements for weighing equipment and are calibrated according to the manufacturer’s instructions. If WMA is approved by the Engineer, modify the mixing plant as required by the manufacturer and WMA additive manufacturer.

401-3.06HAULING EQ UIPMENT . Haul HMA in trucks with tight, clean, smooth metal beds

Keep beds free of petroleum oils, solvents, or ot her materials that would adversely affect the mixture. Apply a thin coat of approved asphalt release agent to beds as necessary to prevent mixture adherence. Provide trucks with covers attached and available for use. Do not haul HMA on barges.

401-3.07AS PHALT PAVERS . Use self -propelled asphalt pavers with heated vibratory screed

assemblies to spread and finish HMA to the specified section widths and thicknesses without introducing thermal or material segregation. Equip the paver with a receiving hopper having sufficient capacity for a uniform spreading operation and a distribution system to place the HMA uniformly in front of screed. Use a screed assembly that produces a finished surface of the required smoothness, thickness and texture without tearing, shoving or displacing the HMA. Heat and vibrate screed extensions. Place auger extensions within 20 inches of the screed extensions or per written manufacturer’s recommendations. 125 ALASKA 2020 Equip the paver with a means of preventing segregation of the coarse aggregate particles from the remainder of the HMA when carried from the paver hopper back to the augers. Equip the paver with automatic screed controls capable of operating from a reference line or a ski from either or both sides of the paver. The use of a “La yton Box” or equivalent towed paver is allowed on bike paths, sidewalks, and driveways.

401-3.08ROLLERS . Use rollers designed to compact HMA and capable of reversing without

shoving or tearing the mixture. Select rollers that will not crush the aggregate or displace the HMA. Equip vibratory rollers with separate vibration and propulsion controls. Equip the rollers with an infrared thermometer that measures and displays the surface temperature to the operator. Infrared thermometer may be hand- held or fixed to the roller. Utilize a pneumatic roller in the complement of rollers to compact the leveling course. Use fully skirted pneumatic -tire roller having a minimum operating weight of 3000 pounds per tire.

401-3.09RESERVED.

401-3.10PREPARATIO N OF EXISTI NG SURFACE . Prepare existing surfaces according to the

Contract. Prior to placing HMA, clean existing surfaces of loose material and uniformly coat contact surfaces of curbing, gutters, manholes and other structures with tack coat material meeting Section 402. Treat cold joint surfaces according to 401- 3.17. Before applying tack coat to an existing paved surface, clean and patch the surface. Remove irregularities to provide a reasonably smooth and uniform surface. Remove and replace unstable areas wit h HMA. Clean the edges of existing pavements, which are to be adjacent to new pavement, to permit the adhesion of asphalt materials. Clean loose material from cracks. Fill the cleaned cracks, wider than 1 inch, with HMA tamped in place. Wash and/or sweep the paved surface clean and free of loose materials. Preparation of a milled surface:

creates thin or unstable pavement areas, or where it breaks through existing pavement, remove thin and unstable pavement, and 2 inches of existing base material, compact and replace with an approved HMA.

401-3.11PREPARATIO N OF ASPHALT . Provide a continuous supply of asphalt binder to the

asphalt mixing plant at a uniform temperature, within the recommended mixing temperature range.

401-3.12PREPARATIO N OF AGGREGATES . Dry the aggregate so the moistur e content of the

HMA, sampled at the point of acceptance for asphalt binder content, does not exceed 0.5 percent (by total weight of mix), as determined by ATM 407. Heat the aggregate for the HMA to a temperature compatible with the mix requirements specif ied. Adjust the burner on the dryer to avoid damage to the aggregate and to prevent the presence of unburned fuel on the aggregate. HMA containing soot or fuel is unacceptable per Subsection 105-1.11. 126 ALASKA 2020 401-3.13 MIXING. Combine the aggregate, asphalt bin der, and additives in the mixer in the amounts required by the JMD. Mix to obtain at least 98 percent coated particles when tested according to AASHTO T195. For batch plants, put the dry aggregate in motion before addition of asphalt binder. Mix the HMA wi thin the temperature range determined by the JMD. Upon the Engineer’s request, provide daily burner charts showing start/stop times and temperatures.

401-3.14TEMPORARY STORAGE OF HMA . Silo type storage bins may be used, provided the

characteristics of the HMA remain unaltered. Signs of visible segregation, heat loss, changes from the JMD, change in the characteristics of asphalt binder, lumpiness, and stiffness of the mixture, are causes for rejection. Do not store HMA on barges.

401-3.15PLACING AN D SPREADING . Use asphalt pavers to distribute HMA, including leveling

course and temporary HMA. Place the HMA upon the approved surface, spread, strike off, and adjust surface irregularities. The maximum compacted lift thickness allowed is 3 inches. When multiple lifts are specified in the Contract, do not place the final lift until all lower lifts throughout that section, are placed and accepted. Do not place HMA abutting curb and gutter until curb and gutter are installed, except as approved by the Eng ineer. Do not pave against new Portland cement concrete curbing until it has cured for at least 72 hours. When practicable, adjust elevation of metal fixtures before paving the final lift, so they will be between 1/4 and 1/2 inch below the top surface of the final lift. Metal fixtures include, but are not limited to manholes, valve boxes, monument cases, hand holes, and drains. Use hand tools to spread, rake, and lute the HMA in areas where irregularities or unavoidable obstacles make mechanical spreadin g and finishing equipment impracticable. Place HMA over bridge deck membranes according to Section 508 and the membrane manufacturer's recommendations. Do not mix HMA produced from different plants for testing or paving.

401-3.16COMPACTION . Thoroughly and uniformly, compact the HMA by rolling. In areas not

accessible to large rollers, compact with mechanical tampers or trench rollers. The Lower Specification Limit for density is 92.0 percent of the Maximum Specific Gravity (MSG) as determined by ATM 409. The MSG from the approved JMD is used for the first lot of each type of HMA. The MSG for additional lots is determined from the first sublot of each lot.

401-3.17JOINTS . Place and compact the HMA to provide a continuous bond, texture, and

smoothness between adjacent sections of the HMA. Minimize the number of joints. Do not construct longitudinal joints in the driving lanes unless approved by the Engineer in writing at the pre- paving meeting. Offset the longitudinal joints in one layer from the joint in the layer immediately below by at least 6 inches. Align the joints of the top layer at the centerline or lane lines. Where preformed marking tape striping is required, offset the longitudinal joint in the top layer not more than 6 inches from the edge of the stripe. 127 ALASKA 2020 Form transverse joints by saw -cutting back on the previous run to expose the full depth of the course or by using a removable bulkhead. Skew transverse joints 15 to 25 degrees. For all joints below the top lift, uniformly coat joint surfaces with tack coat material meeting When Item 401.0014.____ appears in the bid schedule, uniformly coat the joint face of all top lift joints with a joint adhesive. Otherwise use tack coat material meeting Section 402. Follow joint adhesive manufacturer’s recommendations for temperatures and application method. Remove joint adhesive applied to the top of pavement surface. If infrared joint heaters are used and passing joint densities are achieved in each of the first three joint densities taken, then joint adhesive is not required. The Lower Specification Limit for top lift longitudinal joint density is 91.0 percent of the MSG of the panel completing the joint. MSG will be determined according to ATM 409. When the longitudinal joint density test result for a top lift panel sublot is less than 91.0 percent, seal the surface of all longitudinal joints within that sublot using a joint sealant meeting Subsection 702- 2.06.Apply joint sealant according to the manufacturer’s recommendations while the HMA is clean, free of moisture and prior to final traffic marking. Place the sealant at a maximum application rate of 0.15 gallons per square yard, and at least 12 inches wide centered on the longitudinal joint. After surface sealing, inlay by gri nding pavement striping into the sealed HMA. Use grooving equipment that grinds a dry cut to groove the width, length, and thickness of the striping within the specified striping tolerances. Correct improperly formed joints that result in surface irregular ities according to a corrective action plan. Joints formed by paving in echelon while the mat temperature is over 200°F, as measured by the Engineer, within three inches of the joint are considered hot lapped and do not require tack coat or joint adhesiv e. When Item 401.0009.____ appears in the Bid Schedule:

incentive without testing for joint density.

401-3.18SURFACE RE QUIREMENTS AND TOLER ANCES. The finished surface of all HMA

paving must match dimensions shown in the contract for horizontal alignment and width, profile grade and elevation, crown slope, and pavement thickness. Water must drain across the pavement surface without ponding. The surface must have a uniform texture, without ridges, puddles, humps, depressions, and roller marks. The surface must not exhibit raveling, cracking, tearing, asphal t bleeding, or aggregate segregation. Leave no foreign material, uncoated aggregate or oversize aggregate on the HMA surface. The Engineer will test the finished surface after final rolling at selected locations using a 10- foot straightedge. Measurements will include spanning joints. The Engineer will identify pavement areas that deviate more than 3/16 inch from the straightedge, including joints, as defective work. Perform corrective work by removing and replacing, grinding, cold milling or infrared heating such areas as required. Do not surface patch. After the Contractor performs corrective work, the Engineer will retest the area. When Item 401.0010.____ appears in the Bid Schedule: 128 ALASKA 2020 1. Pavement smoothness will be evaluated for price adjustment according to Subsection 401- 4.03.3.

lanes for surface smoothness within 21 days after paving is complete and driving lanes are delineated. Profiler measurements will be taken on through lanes identified in the contract. Profiler measurements will not be taken in turn lanes, intersections, ramps, lane transitions, or within 25 feet of bridge abutments and transverse joints with pre- existing pavement. The Engineer will measure the pavement smoothness in both wheel paths of each lane. The smoothness is measured as International Roughness Index (IRI), reported as inches/mile, at 0.1 mile increments. Pavement smoothness is the average of all IRI measurements for the project. The Engineer will identify areas requiring corrective action in accordance with Table 401- 4. Perform full -width corrective action in those areas. The Engineer may waive corrective work for localized roughness for deficiencies resulting from manholes or other similar appurtenances near the wheel path. Perform Corrective Actions according to one of the following or by a method approved by the Engineer:

grind to the required surface tolerance and cross section. Remove and dispose of all materials resulting from the grinding process. Apply joint sealant and sand to exposed aggregates per the manufacturer’s recommendations.

match the overlay to the existing pavement. Apply tack coat on the milled surface and joint adhesive to all vertical joints and overlay the full width of the underlying pavement surface. Use the same approve d HMA for overlays. Place a minimum overlay thickness of 2.0 inches.

coat to the milled surface and joint adhesive to all vertical joints prior to inlay new HMA to match the existing pavement. Use the same approved HMA. Place a minimum thickness of 2.0 inches. After completion of corrective work, the Engineer will measure the pavement surface with an inertial profiler for a smoothness price adjustment.

401-3.19REPAIRING DEFEC TIVE AREAS . Remove HMA that is contaminated with foreign

material, is segregated (determined visually or by testing), flushing, or bleeding asphalt. Remove and dispose defective HMA for the full thickness of the course. Cut the pavement so that edges are vertical and the sides are parallel to the direction of traffic. Coat edges with a tack coat according to Section 402. Place and compact fresh HMA so that compaction, grade and smoothness requirements are met.

401-3.20ROADWAY MA INTENANCE . Inspect daily according to pavement inspection plan

Remove, and dispose of project materials incorrectly deposited on existing and new pavement surfaces(s) inside and outside the project area including haul routes. The Contractor is responsible f or damage caused by not removing these materials and any damage to the roadway from the removal method(s). Repair damage to the existing roadway that results from fugitive materials or their removal.

401-4.01METHOD OF MEASUREMENT . See Section 109 and th e following:

129 ALASKA 2020 1. Hot Mix Asphalt .

additive or cutting back joints. If the use of WMA is approved by the Engineer, WMA additives will not be measured and are considered subsidiary to the HMA pay item.

2 Asphalt Binder . By weight, as follows: Method 1 will be used for determining asphalt binder quantity unless otherwise directed in writing. The procedure initially used will be the one used for the duration of the project. No payment is made for any asphalt binder more than 0.4 percent above the optimum asphalt binder content specified in the JMD.

represented by tha t sublot. The Engineer will use either ATM 405 or ATM 406 to determine the percent of asphalt binder. The same test method used for the acceptance testing of the sublot will be used for computation of the asphalt binder quantity. In the absence of testi ng, the percent of asphalt binder is the target value for asphalt binder in the JMD.

Engineer’s option for projects where deliveries are made in tankers and the asphalt plant is producing HMA for one project only. The Engineer may direct, at any time that tankers are weighed in the Engineer’s presence before and after unloading. If the weight determined at the project varies more than 1 percent from the invoice amount, p ayment is based on the weight determined at the project. Any remnant or diversion will be calculated based on tank stickings or weighing the remaining asphalt binder. The Engineer will determine the method. The weight of asphalt binder in disposed HMA is c alculated using the target value for asphalt binder as specified in the JMD.

to the HMA class and type.

strip additive.

weight of asphalt binder or anti -strip additive.

under Subsection 401- 4.03.2.

FHWA’s ProVAL software under Subsection 401- 4.03.3.

additive. 130 ALASKA 2020 12. Crack Repair. From end to end of the crack repaired according to 401- 3.10, measured horizontally along the centerline of the crack. Cleaning loose material from cracks, asphalt binder, and HMA to fill cracks will not be measured separ ately but are subsidiary.

placed according to 401- 3.10(1), measured according to Section 109. Asphalt binder, HMA, and cleaning loose material, will not be measured separately but are subsidiary.

3.10(2), measured according to Section 109. Asphalt binder, HMA, and removal of pavement and base course will not be measured separately but are subsidiary.

401-4.02ACCEPTANCE SAMPLING AND TESTING . The bid quantity of each type of HMA

produced and placed will be divided into lots and the lots evaluated individually for acceptance. A lot is normally 5,000 tons. The lot is divided into sublots of 500 tons, each randomly sampled and tested for asphalt binder content, density, and gradation according to this Subsection. The lot is evaluated for price adjustment according to Subsection 401- 4.03.1. Seasonal startup or a new JMD requires starting a new lot. If less than 8 sublots have been placed at the time a lot is terminated, the material in the shortened lot will be included as part of the prior lot. The price adjustment computed for the prior lot will include the samples from the shortened lot . Density test results from material in the shortened lot will be based on the MSG of the shortened lot. If there is no prior lot, and there are at least 3 sublots, the material in the shortened lot will be considered as a lot and the price adjustment wi ll be based on the actual number of test results in the shortened lot. If there are less than 3 sublots, the HMA will be accepted for payment based on the Engineer’s approval of the JMD, and placement and compaction of the HMA to the specified depth, finis hed surface requirements and tolerances. The Engineer reserves the right to perform any testing required in order to determine acceptance. If 8 or 9 sublots have been placed at the time a lot is terminated, they will be considered as a lot and the price adjustment will be based on the actual number of test results in the shortened lot. If the bid quantity is between 1,500 to 4,999 tons, the quantity is considered one lot. The lot is divided into sublots of 500 tons, each randomly sampled and tested for as phalt binder content, density, and gradation according to this Subsection. The lot is evaluated for price adjustment according to Subsection 401- 4.03.1. For bid quantity less than 1,500 tons, HMA will be accepted for payment based on the Engineer’s approval of the JMD, and placement and compaction of the HMA to the specified depth, finished surface requirements and tolerances. The Engineer reserves the right to perform any testing required in order to determine acceptance. Sampling and testing include the following:

presence of the Engineer from behind the paver screed before initial compaction, or will be taken randomly by the Engineer from the windrow, according to ATM 402 or ATM 403, at the discretion of the Engineer. The location (behind the paver screed or windrow) will be determined at the pre- paving meeting. Random sampling locations will be determined by the Engineer. Two separate samples will be taken, one for acc eptance testing and one held in reserve for retesting if requested. Asphalt binder content will be determined according to ATM 405 or ATM 406, at the discretion of the Engineer. 131 ALASKA 2020 2. Aggregate Gradation. Aggregates tested for gradation acceptance will have the full tolerances from Table 401- 2 applied.

conveyor via a diverter device, from the stopped conveyor belt or from the same location as samples for determination of asphalt binder content, at the discretion of the Engineer. Two separate samples will be taken, one for acceptance testing and one held in reserve for retesting if requested. The aggregate gradation for samples from the conveyer system will be determined according to ATM 304. For HMA samples, the gradation will be determined according to ATM 408 from the aggregate remaining after the ignition oven (ATM 406) has burned off the asphalt binder. Locate diverter devices for obtaining aggregate samples from drum mix plants on the conveyor system delivering combined aggregates into the drum. Divert aggregate from the full width of the conveyor system and maintain the diverter device to provide a representative sample of aggregate incorporated into the HMA.

or from the same location as samples for determination of asphalt binder content, at the discretion of the Engineer. Two separate samples will be taken, one for acceptance testing and one held in reserve for retesting if requested. The aggregate gradation for dry batch samples will be determined according to ATM 304. For HMA samples, the gradation will be determined according to ATM 408 from the aggregate remaining after the ignition ov en (ATM 406) has burned off the asphalt binder.

each core sample.

and the Engineer's judgment. Take no mat cores within 1 foot of a joint or edge. Core samples are not taken on bridge decks.

centered on the visible surface joint, and adjacent to the mat core sample taken in the panel completing the joint. Take core samples according to ATM 413 in the presence of the Engineer. Cut full depth core samples, centered on the marks and as noted above, from the finished HMA within 24 hours after final rolling. Neatly core drill one six inch diameter sample at each marked location. Use a core extractor to remove the core - do not damage the core. The Engineer will immediately take possession of the samples. Backfill and compact voids left by coring according to ATM 413. The Engineer will determine density of samples according to ATM 410.

for asphalt binder content, gradation, and density may be requested provided the quality control requirements of Subsection 401- 3.02 are met. Deliver this request in writing to the Engineer within 7 days of receipt of the final test of the lot. The Engineer will mark the sample location for the density retest within a 2 foot radius of the original core. The original test results are discarded and the retest result is used in the price adjustment calculation regardless of whether the retest result gives a higher or lower pay factor. Only one retest per sample is allowed. When gradation and asphalt binder content are determined from the same sample, a request for a retest of either gradation or asphalt binder content results in a retest of both. Both gradation and asphalt binder content retest results are used in the price adjustment calculation. Retesting will be performed by a department laboratory. 132 ALASKA 2020 5. Asphalt Binder Grade. The lot size for asphalt binder is 200 tons. If a project has m ore than one lot and the remaining asphalt binder quantity is less than 150 tons, it is added to the previous lot and that total quantity will be evaluated as one lot. If the remaining asphalt binder quantity is 150 tons or greater, it is sampled, tested and evaluated as a separate lot. If the bid quantity of asphalt binder is between 85 – 200 tons, the contract quantity is considered as one lot and sampled, tested, and evaluated according to this subsection. Quantities of asphalt binder less than 85 tons will be accepted based on manufacturer’s certified test reports and certification of compliance. Sample asphalt binder at the plant from the supply line in the presence of the Engineer according to ATM 401. The Engineer will take immediate possession of the samples. Take three samples from each lot, one for acceptance testing, one for Contractor requested retesting, and one held in reserve for referee testing if requested. Meet Subsection 702 requirements for asphalt binder quality.

the quality control requirements of Subsection 401- 3.02 are met. Deliver the request in writing to the Engineer within 7 days of receipt of notice of failing test. The original test results are discarded and the retest result is used for acceptance. Only one retest per sample is allowed. If the contractor challenges the result of the retest, the referee sample held by the Engineer will be sent to a mutually agreed upon independent AAS HTO accredited laboratory for testing. The original acceptance test result, the retest acceptance test result, and the referee sample test result will be evaluated according to ASTM D3244 to obtain an Assigned Test Value (ATV). The ATV value will be used to determine if the asphalt binder conforms to the contract. The Contractor shall pay for the referee sample test if the ATV confirms the asphalt binder does not meet contract requirements.

401-4.03EVALUATION OF MATERIALS FOR ACC EPTANCE

The Engineer m ay reject material which appears to be defective based on visual inspection. If a test of rejected material is requested, a minimum of two samples are collected from the rejected material and tested. If all test resul ts are within specification limits, p ayment for the material is made. The following methods are applied to each type of HMA when Price Adjustment Pay Items are included in the Bid Schedule. These methods describe how price adjustments are determined based on the quality of the HMA, longitudi nal joint density and pavement smoothness.

and mat density are used in HMA price adjustment. These test results for a lot are analyzed collectively and statistically by the Quality Level Analysis (QLA) method as specified in Subsection 106- 1.03.3 to determine the total estimated percentage of the lot that is within specification limits. The values for percent passing the #200 sieve, asphalt binder content and density t est results are reported to the nearest 0.1 percent. All other sieves used in QLA are reported to the nearest whole number. The HMA price adjustment is based on the lower of two pay factors. The first factor is a composite pay factor (CPF) for HMA that i ncludes gradation and asphalt binder content. The second is the density pay factor (DPF). A lot containing material with less than a 1.000 pay factor is accepted at an adjusted price, provided that pay factor is at least 0.800 and there are no isolated defects identified by the Engineer. A lot containing material that fails to obtain the minimum pay factor is considered unacceptable and rejected under Subsection 105- 1.11. 133 ALASKA 2020 HMA pay factors are computed as follows:

Adjustment programs.

tolerances in Table 401- 2, or as shown below. The TV is the specification value shown in the approved Job Mix Desi gn. TABLE 401 -2 HMA LOWER SPECIFICATION LIMIT ( LSL) & UPPER SPECIFICATION LIMIT ( USL)

determined by the Engineer for each Lot in accordance with Subsection 106- 1.03.3. The Composite Pay Factor (CPF) for the lot is determined from gradation and asphalt binder content (ac) acceptance t est results using the following example formula: [f 3/4 inch (PF 3/4 inch ) + f 1/2 inch (PF 1/2 inch ) +....f ac (PF ac)] CPF = Σf Table 401- 3 gives the weight factor (f) for each test property considered. TABLE 401 -3 WEIGHT FACTORS Property Type I Factor “ f” Type II Factor “f” Type III Factor “f” 1 inch sieve 4 - - ¾ inch sieve 4 4 - ½ inch sieve 4 5 4 3/8 inch sieve 4 5 5 No. 4 sieve 4 4 5 No. 8 sieve 4 4 5 No. 16 sieve 4 4 5 No. 30 sieve 4 5 6 No. 50 sieve 4 5 6 No. 100 sieve 4 4 4 No. 200 sie ve 20 20 20 Asphalt Content, % 40 40 40 Measured Characteristics LSL USL ¾” or largest sieve size 99 100 ½ inch sieve or first sieve retaining aggregate TV-6 TV+6 3/8 inch sieve TV-6 TV+6 No. 4 sieve TV-6 TV+6 No. 8 sieve TV-6 TV+6 No. 16 sieve TV-5 TV+5 No. 30 sieve TV-4 TV+4 No. 50 sieve TV-4 TV+4 No. 100 sieve TV-3 TV+3 No. 200 sieve TV-2.0 TV+2.0 Asphalt Binder Content, % TV-0.4 TV+0.4 Mat Density, % 92.0 100.0 134 ALASKA 2020 The Density Pay Factor (DPF) is computed using HMA mat core compaction acceptance test results. The CPF and DPF are rounded to the nearest 0.001. The price adjustment for each individual lot is calculated as fol lows: HMA Price Adjustment = [(CPF or DPF)* - 1.00] x (tons in lot) x (PAB) * CPF or DPF, whichever is lower PAB = Price Adjustment Base = [Bid Unit Price for 401.0001.___ + (n/100) x Bid Unit Price for 401.0004.____], Where n = Optimum asphalt binder content percent, established by the JMD. The HMA Price Adjustment is the sum of the price adjustments for each lot and paid for under Item 401.0008.____.

be based on the project average of all top lift joint densities and determined as follows:

disincentive: Longitudinal joint density price adjustment equal to $3.00 per lineal foot is deducted.

following incentive: Longitudinal joint density price adjustment equal to $1.50 per linear foot is added. The Longitudinal Joint Density Price Adjus tment is the total price adjustment paid for under Item 401.000 9.____ .

Engineer and reported as IRI (inches/mile), according to Subsection 401- 3.18. Incentive for pavement smoothness shall apply only if both the project average CPF and DPF are greater than or equal to 1.000. Disincentive for pavement smoothness shall apply regardless of the project average CPF or DPF. The Engineer will calculate the pavement smoothness price adjustment according to Method 1 or Method 2 below, as identified in the bid schedule. Method 1: SPA = PAB x PQ x SF, Where: SPA = Pavement Smoothness Price Adjustment PAB = Price Adjustment Base PAB = [Bid Unit Price for 401.0001.____ + (n/100) x Bi d Unit Price for

401.0004.____],

n = optimum asphalt binder content, percent, established by the JMD PQ = Top layer HMA quantity, tons SF = Smoothness Factor (Table 401- 4) TABLE 401 -4 SMOOTHNESS FACTOR (SF) IRI (in./mile) SF Less than 40 0.05 135 ALASKA 2020 IRI (in./mile) SF 40 to 70 0.05 – (IRI - 40)/600 70 to 90 0.00 90 to 120 (90 – IRI)/120 Greater than 120* - * Corrective Work required, see Subsection 401- 3.18 Method 2: SPA = PAB x PQ x SF, Where: SPA = Pavement Smoothness Price Adjustment PAB = Price Adjustment Base PAB = [Bi d Unit Price for 401.0001.____ + (n/100) x Bid Unit Price for

0 4.____],

n = optimum asphalt binder content, percent, established by the JMD PQ = Top layer HMA quantity, tons SF = Smoothness Factor = 0.12 x RR – 0.02; SF not to exceed 0.05 RR = Roug hness Reduction = (Initial IRI – Final IRI) / Initial IRI Initial IRI = Pre-project average IRI as measured and reported by the Engineer. The Initial IRI will either be included in the bid documents or the timeline for when the Initial IRI will be measured will be identified in the bid documents. Final IRI = Top layer HMA average IRI as measured and reported by the Engineer according to Subsection 401- 3.18. The Pavement Smoothness Price Adjustment is the total price adjustment paid for under Item 401.0010 .____.

401-4.04ASPHALT MA TERIAL PRICE ADJUSTM ENT

Asphalt Material Price Adjustment. This subsection provides a price adjustment for asphalt material by: (1) additional compensation to the contractor or (2) a deduction from the contract amount.

date on the certified bill of lading from the asphalt material refiner/producer.

of lading from the asphalt refiner/producer.

remain in effect f rom the day of calculation until the next bimonthly calculation. The AAMPI is posted on the Department’s Statewide Materials website at and calculated according to the formula posted there. http://www.dot.state.ak.us/stwddes/desmaterials/aprice_index.shtml

AAMPI in effect on the date of the certified bill of lading from the asphalt material refiner/producer, to calculate the price adjustment for asphalt material The Department will 136 ALASKA 2020 increase or decrease payment under this contract by the amount determined with the following asphalt material price adjustment formula: For an increase exceeding 7.5 percent, additional compensation = [(IPP – IB) – (0.075 x IB)] x Q For a decrease exceeding 7.5 percent, deduction from contract = [(IB – IPP) – (0.075 x IB)] x Q Where: Q = Quantity of Asphalt Material incorporated into project during the pay period , in tons as measured by the Engineer IB = Index at Bid: the Bi -monthly AAMPI in effect on date of bid, in dollars per ton IPP = Index at Pay Period: The bi -monthly AAMPI in effect on the date shown on the certified bill of lading from the asphalt refiner /producer, in dollars per ton

meets the criteria of this subsection and is incorporated into the project. The quantity does not include aggregate, mineral filler, blo tter material, thinning agents added after material qualification, or water for emulsified asphalt. The quantity for emulsified asphalts will be based on the asphalt residue material only and will be calculated using the percent residue from testing, or i f not tested, from the manufacturer’s certificate of compliance.

401-5.01BASIS OF PA YMENT

Asphalt binder, liquid anti -strip additives and tack coat are subsidiary to HMA Item 401.0001.____ and 401.0006.____ unless specified as Pay Items. Asphalt binder and liquid anti -strip are subsidiary to HMA for Items 401.0002.____, 401.0003.____, 401.0005.____, 401.0011.____, and

12.____

Item 401.0008 .____ HMA price adjustment is the sum of the price adjustments for each material lot and for deductions and f ees assessed. Deductions and fees assessed include:

subsequent evaluations required to obtain an approved JMD will be assessed a fee of $6,000 per evaluation. Failed retest will result in a fee of $2,500.

sample per day.

$100 per hole per day.

not meet contract requirements, a fee of $500 will be assessed. Item 401.0008.____ HMA price adjustment does not apply to:

137 ALASKA 2020 Payment will be made under: PAY ITEM Item Number Item Description Unit

01.____ HMA, T ype ___; Class ___ TON

02.____ HMA, Leveling Course, Type ___; Class ___ LnSt

03.____ HMA, Leveling Course, Type ___; Class ___ TON

04.____ Asphalt Binder, Grade ____ TON

05.____ HMA, Temporary, Type ___; Class ___ TON

06 .____ HMA, Type ___; Class ___ SY

07.____ Liquid Anti -Strip Additive CS

08.____ HMA Price Adjustment, Type ___; Class ___ CS

09.____ Longitudinal Joint Density Price Adjustment CS

10.____ Pavement Smoothness Price Adjustment, Me thod ___ CS

11.____ HMA, Driveway, Type ___; Class ___ LS

12.____ HMA, Driveway, Type ___; Class ___ TON

13.____ Job Mix Design EACH

14.____ Joint Adhesive LF

15.____ Asphalt Material Price Adjustment CS

16.____ Crack Repair LF

17.____ Prelevel for Ruts, Delaminations, and Depressions SY

18.____ Repair Unstable Pavement SY

138 ALASKA 2020 SECTION 402 TACK COAT

402-1.01DESCRIPTION . Apply an asphalt tack coat on an approved surface

402-2.01MATERIALS. Use mater ials that conform to the following:

Asphalt Section 702 (STE -1) CONSTRUCTION REQUIREMENTS

402-3.01WEATHER LIM ITATIONS. Do not apply tack coat to a wet surface or when the

roadway surface temperature is below 40 °F.

402-3.02EQUIPMENT. Furnish, maintain, and operate asphalt distributor to apply asphalt

material uniformly at even heat on variable widths of surface up to 15 feet at readily determined and controlled rates from 0.01 to 0.11 gallon per square yard, with uniform pressure, and with an allowable va riation from any specified application rate not to exceed 0.02 gallon per square yard. Equip with a heater, tachometer, pressure gauges, calibrated tank, thermometer for measuring temperatures of tank contents, power unit for the pump and full circulation spray bars adjustable laterally and vertically.

402-3.03PREPARATION OF SURFACE TO BE TR EATED. Clean and patch the existing

surface to receive the treatment. Remove irregularities to provide a reasonably smooth and uniform surface. Remove and replace unstable corrugated areas with suitable patching materials. Clean the edges of existing pavements, which are to be adjacent to new pavement, to permit the adhesion of asphalt materials.

402-3.04APPLICATION OF ASPHALT MATERIAL . Apply tack coat uniformly with a pressure

distributor at a rate of 0.04 to 0.10 gallon per square yard, as directed. Apply the tack coat in such a manner as to offer the least inconvenience to traffic and to permit one-way traffic without pickup or tracking of the asphalt material. Limit application of tack coat so it will be covered by paving within one day.

402-4.01METHOD OF M EASUREMENT. See Section 109

402-5.01BASIS OF PA YMENT. Payment for patching existing surfaces will be made at the

contract unit price for the various items used unless a reconditioning item is included in the Contract. Payment will be made under: PAY ITEM Item Number Item Description Unit

402.0001. ____ STE-1 Asphalt for Tack Coat TON

02. ____ STE-1 Asphalt for Tack Coat LS