409.06 Basis of Payment.
The length shall be the actual length measured along the surface of the treatment. The width shall be the designated width of completed su rface. Where the pay item specifies a prime coat plus an overlying treatment, the measurement will not include the additional width of the prime coat.
409.06 Basis of Payment.
a.Unit Price Coverage. Payment for accepted triple layer bituminous surface t reatment , Pay Item No. 409 -A Triple Layer Bituminous Treatment, measured as provided above, will be paid for at the contract unit price per square yard {square meter} complete in place; except that adjustments in the contract unit price shall be made as fo llows: When changes in amounts of treatment materials are ordered as provided in Article 409.01, the contract unit price will be adjusted upward or downward accordingly. Adjustment will be based on the increase or decrease in amounts per square yard {square meter}, at the verified cost, f.o.b. delivery point plus 2 cents per gallon {0.5 cent per liter} for the bitumen, and the verified cost per square yard {cubic meter} for the aggregate delivered to the spreader. The contract unit price or adjusted contrac t unit price for the accepted area complete in place shall be payment in full for furnishing all material, placement of materials, maintenance thereof and for all equipment, tools, labor, and incidentals necessary to complete the work.
b.Payment will be made under Item No.: 409-A Triple Layer Bituminous Treatment , - per square yard {square meter} ASPHALT PAVEMENTS
410.01 Description.
The work under this Section covers the general requirements that are applicable to all types of hot and warm mix asphalt pavements of the plant mix type. Deviations from these general requirements will be indicated in the specific requirements for various types of mixes noted in the following sections of these Specifications. This work shall consist of one or more courses of hot and warm mix asphalt plant mix constructed in accordance with these specifications and the specific requirements of the type of mixture required and in reasonably close conformity with the lines, grades, thicknesses, and typical c ross sections shown on the plans or established by the Engineer. The Contractor may use either hot mix or warm mix for all Superpave ESAL Range mixes in Section 424. Warm mix asphalt shall be defined as the use of an approved warm mix technology in the pla nt mix at the time of production. This work shall also include the preparation of the underlying surface on which the plant mix is to be placed, including patching and/or leveling as shown on the plans or directed by the Engineer . In addition, this work shall also include the placing of widening at locations shown on the plans and/or directed by the Engineer. In general, widening shall consist of (1) narrow width build -ups, three feet or less {one meter or less}, required for widening existing pavement, (2) paving for turn -outs beyond three feet {one meter} from the edge of pavement, (3) pavement crossovers, and (4) turning lanes of less than 200 feet {60 m} for crossovers. Paving used on turn -outs for intersecting paved roads and shoulder paving will not be considered as widening unless shown on the plans. Surface layers and wearing layers are defined as those layers where the pay item contains the wording “Wearing Surface”. All ALDOT procedures referenced are applicable to both hot and warm mix aspha lt.
410.02 Materials.
a.Applicable Sections of Specifications . Materials shall conform to requirements given in Sections 327, 420, 423 and 424.
b.Products and Processes for the production of Warm Mix Asphalt . Warm Mix Asphalt products and processes sh all be selected from List II -27, “Warm Mix Asphalt Products and Processes” of the Department's manual titled "Materials, Sources, and Devices with Special Acceptance Requirements". Information concerning this list is given in Subarticle 106.01(f) and ALDOT - 355.
410.02 Materials.
c.Anti-Stripping Agents . All warm mix asphalt mixtures , 327E mixes, and 420 mixes shall include an anti -stripping agent. The warm mix additive supplier may certify that an anti -stripping agent is an integral part of the warm mix additive. All hot mix asphalt mixtures except 327 E and 420 shall be tested during design to determine if an anti-stripping agent is needed. During design and production, all other mixes shall have a tensile strength ratio (TSR) of at least 0.80 when tested in accordance with AASHTO T 283 as modified by ALDOT -361. If any TSR value falls below the minimum specified above, plant operations shall cease until corrective measures are taken. However, if any visual stripping occurs in the design or field production, an anti -stripping agent shall be required if deemed necessary by the Engineer. Should it become necessary for the Contractor to include an anti -strip agent in the mix due to the occurrence of visual stripping during field production of the mix after the design tests indica ted that the same mix met the above listed TSR requirement, such work will be paid for as Extra Work as defined by Article 104.03. Additional payment for the anti -strip agent will not be made in cases where the same mix has been previously used in field pr oduction and visual stripping occurred.
1.Amines. For amine based materials, t he amount of anti -stripping agent, when required, shall be 0.25 to 1.0 % by weight {mass} of the liquid asphalt binder content for liquid agents and 0.5 to 2.0 % by weight {mass} of the total aggregate for powdered agents. Liquid anti -stripping agent shall be added to the liquid asphalt binder within ±10% of the specified rate, either at the refinery or the Contractor's mixing plant, using approved on -line blending equipment.
2.Hydrated Lime. For hydrated lime materials the amount of anti -stripping agent, when required, shall be 0.5 to 2.0 % by weight {mass} of the total aggregate for powdered agents. Hydrated lime materials shall meet the requirements as given in Section 805.
3.OrganoSilanes. For organosilane based materials the amount of anti -stripping agent, when required, shall be 0.05 to 0.1 % by weight {mass} of the liquid asphalt binder content for liquid agents. Liquid anti-stripping agent shall be added to the liquid a sphalt binder by approved on -line blending equipment either at the refinery or the Contractor's mixing plant within ± 10% of the specified rate.
4.Silicone Silicone may be used in liquid asphalt binder, not to exceed 2 ounces per 5000 gallons {3 ml per 1000 L}. Except when producing Warm Mix Asphalt, other additives shall not be added to the liquid asphalt binder unless expressly authorized in writing by the Materials and Tests Engineer. The use of any unauthorized additive will be cause for rejection of t he mixture.
5.Warm Mix Asphalt Additives Approved Warm Mix Asphalt Additives from ALDOT list II -27 May be used in liquid Asphalt Binder as an anti -striping agent when used as directed by the Manufacturer. The use of any unauthorized additive will be cause for rejection of the mixture.
d.Composition of Mixtures .
1.Adjustments to Rate of Placement. The project designated rate per square yard {square meter} of the plant mix layers are designed assuming a compacted mix unit weight {mass} of not greater than 158 pounds per cubic foot {2530 kg/m 3} for dense graded mixes (light weight aggregates excepted.) Hence, a correction to the plan designated rate per square yard {square meter} will be made in accordance with the following: • If the compacted mi x density as determined in the job mix formula design exceeds 158 , or is below 130, pounds per cubic foot, {2530 kg/m3, or is below 2080 kg/m3}, the correction will be based on the formula: x = ab/158 {x = ab/2530} , where x = corrected rate per square yard {square meter}, a = laboratory compacted mix unit weight in pounds per cubic foot {density in kilograms per cubic meter} as shown in the job mix formula, and b = project designated rate per square yard {square meter} of plant mix as shown on the job plans. • If the laboratory compacted density is between 130 pounds per cubic foot and 158 pounds per cubic foot {2080 kg/m3 and 2530 kg/m3}, no correction will be made to
410.02 Materials.
the pounds per square yard {kilograms per square meter} designated by the plans or proposal. • If the plans provide for the use of lightweight aggregate (expanded clay or shale), the pounds per square yard {kilograms per square meter} of the layer shown by the plans or proposal will not be adjusted. • If the plans provide for the use of a n "Open Graded" plant mix layer, the pounds per square yard {kilograms per square meter} of the layer shown by the plans or proposal will not be adjusted.
2.Requirement for Approved Job Mix Formula (JMF). Work shall not be started under this Section on a specific project until the Contractor has submitted and received approval of a job mix formula from the Materials and Tests Engineer and the job mix formula has been checked by the Area Materials Engineer for use on the project. A change in aggregate sourc es will require a new job mix formula before the new material is used. A change in liquid asphalt binder source and anti -stripping agent will be allowed without a new job mix formula provided the design criteria is met by a one- point check of the mixture. The one -point check shall include the Air Void content , VMA, Stability, Flow, and TSR (Tensile Strength Ratio) and may be determined during the production of the mix. However, no change in the grade of liquid asphalt binder will be allowed without the wri tten approval of the Materials and Tests Engineer.
3.Contractor's Responsibility for Job M ix Formula. Designs for all mixes shall be the responsibility of the Contractor and shall be submitted by the Contractor for approval. Refer to applicable Sections ( 420, 424, etc.) for design criteria. The submitted formula shall have been designed by a certified technician (Level III - Designer) in a laboratory that has been certified by the Department.
4.Approval of Job Mix Formula by Materials and Tests Engineer. The Contractor shall submit to the Materials and Tests Engineer, for approval, a Job Mix Formula (JMF) for each mixture to be supplied from a specific plant. The Contractor shall allow at least four weeks for the evaluation and approval of the job mix form ula. The submitted formula shall include any additive by type and trade name and be accompanied by samples from the material sources the Contractor proposes to use in producing the mix. The job mix formula for each mixture shall establish a single percent age of aggregate passing each required sieve size, a single percentage of liquid asphalt binder to be added to the aggregate, a single percentage of any additive, and a mixing temperature range suitable for the type, grade, etc. of liquid asphalt binder to be used in the mix. Each job mix formula shall be accompanied by a test report from an approved laboratory certifying that all current Departmental design test parameters have been met (copies of the Departmental current design test parameters may be obta ined from the office of the Materials and Tests Engineer). There will be no charge for the Department's checking of the Contractor's job mix formula. The approved j ob mix formula for each mixture shall be in effect for a maximum of two years from the approval date on the job mix formula or until the Materials and Tests Engineer withdraws approval by written order.
5.Approval of Job Mix Formula by Area Materials Engineer. At least two full working days prior to beginning the production of asphalt mix for a specific project, the Contractor shall submit a mix design (approved by the Materials and Tests Engineer) to the Area Materials Engineer. The project number shall be inserted on the approved job mix formula. The Area Materials Engineer will review the mix design to determine if the job mix formula is appropriate for the specific project. If the job mix formula is appropriate for the project, the Area Materials Engineer will sign the mix design as being approved, will note the date of approval, and will distribute copies for inspection of the asphalt production. A copy of this approved job mix formula with the Materials and Tests Engineer's approval and the Area Materials Engineer's approval (with the date of approval) shall be available at the plant any ti me material is being delivered to the State.
6.Establishment of Delivery Temperature. The Engineer will check and record the temperature of the mixture upon delivery to the project site. The minimum delivery temperature for warm mix asphalt shall be 220 ° F {104 °C}. The minimum delivery temperature for hot mix asphalt shall be 250 °F {121 °C}. The Engineer should monitor the work to ensure that there is not high variability in the delivery temperatures or isolated loads of temperature differentials that appear extreme. For pay items that do not require density as a pay
410.02 Materials.
factor (patching, widening, etc.) and for mixes that do not require density as a pay factor (OGFC, PATB, etc) the Contractor shall provide a +/ - 25 oF {11 oC} delivery temperature range. No loads will be accepted at a temperature greater than 350 °F {177 °C} for hot mix or warm mix asphalt.
7.Conformance to Approved Job Mix Formula. All mixtures furnished for use on the project shall conform to the approved j ob mix formulas within the following ranges of tolerances: • All liquid asphalt binders used shall meet the requirements given in Section 804. See appropriate pay factor table for liquid asphalt binder content requirements. • The mixing temperature shall not exceed 350 ° F {177 °C}. • Tolerances for 327, 420 and 424 mixes: - Plus or minus 7 % for the #4 {4.75 mm} and larger sieve requirements. - Plus or minus 4 % for the #8 through #100 {2.36 mm through 150 µm} sieve requirements. - Plus or minus 2.0 % for the #200 {75 µ m} sieve requirement. See Section 423 for gradation requirements for 423 mixes. The initial setting of the controls for all materials shall be those amounts shown on the job mix formula. The above tolerances are provided for slight variations inherent in job control applications. The Contractor shall make changes as necessary to ensure that the mixture produced is as close as practical to the job mix formula.
8.Consistency of Mix Design in Placement of Wearing Layer. More than one job mix formula may be submitted and approved for a layer of pavement. The placement of the entire wearing layer shall be from the same job mix unless otherwise approved in writing by the Engineer. For layers other than the wearing layer, the Con tractor shall notify the Engineer in writing of the mix design change prior to changing production.
e.Recycled Asphalt Plant Mix (RAP) and Reclaimed Asphalt Shingles (RAS).
1.Compliance with ALDOT -372. On all projects utilizing recycled/reclaimed material in the mixture, the Contractor's paving operation and RAP and RAS processing shall conform to the requirements given in ALDOT -372. The recycled hot and warm mix asphalt shall be a homogeneous mixture of reclaimed material, new aggregate (fine or coars e aggregate, or a mixture of fine and coarse aggregate) and new liquid asphalt binder material.
2.Allowable Usage of RAP and RAS. The Contractor shall have the option to use RAP and RAS in accordance with the requirements given in the following table unle ss shown otherwise on the plans:
410.02 Materials.
ALLOWABLE USE OF RAP AND RAS Maximum Allowable Percent of RAP and RAS by mass of Total Aggregate Content Type of Mix Maximum RAP Content # Maximum RAP and RAS Content ** 327, Plant Mix Bituminous Base 25 % RAS Not Allowed 327-E, Permeable Asphalt Treated Base RAP Not Allowed RAS Not Allowed 420, Open Graded Friction Course RAP Not Allowed RAS Not Allowed 423, Stone Matrix Asphalt 424, Superpave (Maximum Aggregate Size ½”, ¾”, 1”, 1 ½”) Surface Layers: 20 % with no more than 15 % containing chert *; All Other Layers: 35 % Surface Layers: 20 % *; All Other Layers: 35 % 424, Superpave (Maximum Aggregate Size 3/8”) Surface Layers: 20% All Other Layers: 35% RAS Not Allowed *** * This limitation applies even if the surface layer is to be covered by an Open Graded Friction Course (Section 420). If the aggregate is chert gravel with a bulk specific gravity that is less than 2.550, a maximum of 15 % of the RAP will be allowed. RAP c ontaining chert gravel shall be crushed so that 100 % of the RAP passes the 1/2 inch {12.5 mm} sieve. Additional RAP that does not contain chert gravel may be added to the mixture through a separate feeder. ** RAS shall be limited to 3% by mass of the t otal aggregate content for surface layers and 5 % by mass of the total aggregate content for all other layers. *** For projects where the ADT is less than 100 or the surface to be paved is non-trafficked, RAS may be allowed at the contents given for the o ther 424 Superpave maximum aggregate sizes.
3.Processing and Restrictions for Aggregate in RAP. RAP used in 3/8 inch {9.5 mm} Section 424 "Superpave" maximum aggregate size mix shall be processed so that 100 % of the RAP passes the 1/2 inch {12.5 mm} sieve. For all other mixes, the maximum size of the aggregate in the RAP shall meet the maximum size for the mix specified. The aggregate in the RAP shall meet the aggregat e requirements of the mix it is used in and the requirements given in Sections 801 and 802 (no gravel in Section 327 PATB, Section 420 and Section 423 mixes). RAP used in Section 327 PATB and Section 420 mixes shall be processed so that 100 % of the RAP i s retained on the No. 4 {4.75 mm} sieve.
4.Reclaimed Asphalt Shingles (RAS). Reclaimed Asphalt Shingles (RAS) shall be handled, stored, and used in accordance with the requirements given in ALDOT 372 and the following requirements. The RAS shall be materi als produced as a by -product of the manufacturing process for roofing shingles and/or scrap shingle (from roofing materials). The RAS shall be free from foreign materials such as paper, nails, wood, and metal flashing. The RAS shall be shredded or groun d prior to being incorporated into the mixture. The shredded RAS shall have 100% passing the 1/2 inch {12.5 mm } sieve in any dimension and a minimum of 95% passing the 3/8 inch sieve. In addition to the requirements set forth in ALDOT -372, RAP stockpiles u tilized for job mix formula ’s with RAP content greater than 25 % shall also meet the following requirements. ADDITIONAL RAP STOCKPILE REQUIREMENTS FOR RAP USED IN A JOB MIX FORMULA WITH INCREASED RAP CONTENT Control Parameter Standard Deviation* Asphalt Content 0.5 % % Passing #200 Sieve 1.5 % Sieve with 50 % RAP Passing 5.0 % *Based on a minimum of 10 tests Testing for RAP stockpile shall be included as part of the design JMF submittal.
410.02 Materials.
f.Liquid Asphalt Binder Draindown .
1.Fiber Stabilizer . A fiber stabilizer is required for some mix types (Section 420, 423, etc). For section 420 mixes the warm mix additive Evotherm 3G may be used in lieu of fibers. A fiber stabilizer may be used on other mix types where asphalt binder cement draindown is a problem. Where RAS is included in the job mix formula , fiber stabilizer shall not be required provided the draindown requirements of 0.30% or less are met when tested at 325°F {163°C} and 350°F {176°C} in accordance with AASHTO T305. When fiber or Evotherm 3G is used, the dosage rate shall produce a maximum liquid asphalt binder cement draindown of 0.30 % or less when tested at 325°F {163°C} and 350°F {176°C} in accordance with AASHTO T305. When fiber is used, t he sampling and testing frequency for all mixes for both Contractor and Department testing during production shall be one test for each 5000 tons {metric tons} or portion thereof. The fiber shall be listed on List II -23, Fibers for use in Hot Mix Asphalt (from the Materials, Sources, and Devices with Special Acceptance Requirements (MSDSAR) manual). If pelletized fibers are used, the fiber within the pellet shall be listed on List II -23. All fibers listed on List II -23 shall meet the requirements of either Item 2, 3, or 4 of this Subarticle.
2.Cellulose Fibers. The maximum length of the fiber shall be 0.25 inches {6.35 mm}. A representative 3 gram sample, when heated in a crucible between 1100 and 1200 ° F {595 and 650 ° C} for at least 2 hours, sh all show between 13 % and 23 % non- volatiles. A representative 5 gram sample, when stirred into 100 ml of distilled water, shall have a pH between 6.5 and 8.5 after sitting for 30 minutes. A representative 5 gram sample, when saturated with mineral spirits for 5 minutes and then sieved for 10 minutes on a No. 40 {425 µm} sieve, shall absorb between 4 % and 6 % its own weight of mineral spirits. A representative 10 gram sample, when weighed and placed into a 250 ° F {121 ° C} oven for two hours, shall lose less than 5 % by weight when weighed immediately upon removal from the oven. Sieve analysis of the cellulose fiber shall be either of the following methods: • Using an Alpine Air Jet Sieve (Type LS), a representative 5 gram sample of the fiber is sieved for 14 minutes at a controlled vacuum of 11 psi {75.8 kPa}. The fibers remaining on the screen are weighed. The results of this analysis shall indicate that 60 % to 80 % of the fiber passes the No. 100 {150 µm} sieve. Or: • Using a Mesh Screen Analysis, a representative 10 gram sample of the fiber is sieved using a shaker with two nylon brushes on each screen. The results of this analysis shall indicate that the fi ber has the following amounts passing the specified screens: 75 % to 95 % on the No. 20 {850 µm} sieve, 55 % to 75 % on the No. 40 {425 µm} sieve, and 20 % to 40 % on the No. 140 {100 µm} sieve.
3.Mineral Fibers. When tested in accordance with the Bauer -McNett Classifier (BCM) fractionation method process procedure , the fiber length shall have a maximum mean test value of 0.25 inches {6.35 mm}. By using a phase contrast microscope, and a representative test sample of at least 200 fibers, the fiber diameter shall have a maximum mean test value of 0.0002 inches {5.1 µm}. The shot content passing the No. 60 {285 µm} sieve shall be 85% to 95%. The shot content passing the No. 230 {65 µm} sieve shall be 60 % to 80 %. This is a measure of non -fibrous material det ermined on vibrating sieves (for further information see ASTM C 612).
4.Synthetic Fibers. Synthetic fibers shall include but are not limited to one or a combination of the following: polyolefins (such as polyethylene and polypropylene) and aramids (such a s Kevlar, Twaron and Nomex). Fibers shall be twisted fibrillated, flat fibrillated or monofilament with a maximum fiber length of 0.75 inches {19 mm}
5.Placing Fiber in Mix .
a.Manual Method. Provided it can be demonstrated to the satisfaction of the Engi neer that the proper dosage of the fibers is uniformly distributed into the mix, manual introduction of fibers is acceptable when a batch plant is used to make the mix. When the fibers are available in prepackaged (weighed) containers, proper dosage may be pre-determined per batch. A device is required to interrupt mixture production and warn the plant operator if the operator manually feeding the fiber fails to introduce it properly. Dry mixing time shall be increased at least five seconds to insure adequ ate
410.03 Construction Requirements.
blending. Wet mixing time shall be increased at least five seconds for cellulose fibers and up to five seconds for mineral fibers. Manual introduction of fibers shall not be used in drum plants.
b.Automatic Method. Methodology and equipment for meter ing bulk loose and pelletized fiber into asphalt plants has been developed by the fiber suppliers. Whenever the fiber supplier’s recommendations are more stringent than this specification, the fiber supplier’s recommendations are controlling. This specific ation requires specialized equipment that can accurately proportion and meter, by weight {mass}, the proper amount per batch (for batch plants) or continuously, in a steady uniform manner (for drum plants). Fiber, pelletized or loose, shall not be fed thro ugh the cold feed bins or through the rap bin. These proportioning devices shall be interlocked with the plant system and controlled to +/ - 10% of the weight of the fibers required so as to maintain the correct proportions for all production rates and batch sizes. During the test strip, an equipment calibration check which shows the fiber is being accurately metered and uniformly distributed into the mix shall be performed to the satisfaction of the Engineer. These metering devices shall provide in process high flow (+ 10% or more) and low flow (- 10% or less) plant operator notification and interrupt the mix production where the fiber rate is not properly controlled. The fiber metering system shall also provide a record of feed rate (weight or mass per time) and include a section of translucent pipe for visual confirmation of consistent flow rates. Care shall be taken to insure that the fibers are not entrained in the plant’s exhaust system. If there is any evidence of fiber in the bag -house or wet -washer fin es, the liquid asphalt binder line and/or the fiber line shall be relocated so that the fiber is captured by liquid asphalt binder spray and incorporated into the mix. If there is any evidence of clumps of fibers or pellets at the discharge chute, the cont ractor shall increase the mixing time and/or intensity. This may entail extending the liquid asphalt binder and fiber feeding lines further into the drum.
g.Sampling and Inspection . Aggregates will be accepted in stockpiles in accordance with the Departm ent's Testing Manual provided there is no segregation or contamination, but production of required gradation in the mix shall be the Contractor's responsibility. Liquid asphalt binder will be accepted in accordance with the requirements given in ALDOT -243. The right is reserved to take samples, including aggregates from stockpiles, plant mix from the hot elevator, plant mix from the spreader, liquid asphalt binder from storage tanks at the plant, etc., and to make further tests as needed as a basis for con tinued acceptance of the materials. Samples of the mixture in use will be taken and tested in accordance with Subarticle 106.09(b). When directed, the Contractor shall use mechanical equipment to cut samples for testing from the compacted pavement. Samples not smaller than 4 inches {100 mm} square or 4 inches {100 mm} in diameter for the full depth of the course to be tested shall be taken at the locations directed by the Engineer. Furnishing of suitable approved cutting equipment, the cutting of the samples, and the immediate repair of the sample holes with similar type of material shall be performed by the Contractor without extra compensation. A laboratory shall be furnished for the control of each hot and warm mix asphalt plant in accordance with the pro visions of Section 601.
410.03 Construction Requirements.
a.Equipment . In general, the choice of equipment will be left to the Contractor. It is the Contractor’s responsibility to provide proper sized and amounts of equipment that will produce, deliver t o the roadbed, spread, and compact the plant mixed material in sufficient quantities for the continuous movement of the spreaders under normal operating conditions. The mixing plant, hauling, spreading, and compaction equipment shall meet the requirements listed below; however, other equipment that will produce equally satisfactory results, such as electronically or automatically controlled devices of proven performance, will be considered for use in lieu thereof. The Contractor shall secure the Engineer’s approval of all equipment prior to beginning work and any equipment determined by the Engineer to be unsatisfactory shall be promptly replaced or supplemented.
410.03 Construction R equirements.
1.Requirements for all Plants. Mixing plants shall comply with the requirements of AASHTO M 156 as modified by ALDOT -324, Mixing Plant Requirements for Hot -Mixed, Hot -Laid Asphalt Paving Mixtures . In addition to the above, if a recycled/reclaimed mix is used, the mixing plant shall be modified as necessary to accommodate the use of the reclaimed material and necessary additives. Mixing plants shall be inspected at least annually to insure compliance with the requirements of AASHTO M 156 and ALDOT -324. The Contractor/Vendor will be charged a fee as specified by ALDOT -355, General Information Concerning Materials, Sources, and Devices with Special Acceptance Requirements. If the plant is relocated or substantially modified in any way within a year of the last inspection, an additional inspection and related fee will be required. The plant shall be equipped with a dust collector constructed to waste or store and later return uniformly to the aggregate mixture all or any part of the material collected.
2.Scales . A digital recorder shall be installed as part of the platform truck scales. The recorder shall produce a printed digital record on a ticket of the gross and tare weights {masses} of the delivery trucks along with a time and date print for each ticket. Provisions shall be made so that scales may not be manually manipulated during the printing process, and so interlocked as to allow printing only when the scale has come to rest. The scales and recorder shall be of sufficient capacity and size to accurately determine the weight {mass} of the heaviest loaded truck or tractor trailers that are used for the delivery of the hot and warm mix asphalt from that plant. In lieu of plant and truck scales, th e Contractor may provide either (1) an approved automatic printer system which will print the weights {masses} of the material delivered (evidenced by a weight {mass} ticket for each load), provided the system is used in conjunction with an approved automa tic batching and control system, or (2) an electronic load cell weight {mass} determination system with associated computer hardware and automated printing system. The Contractor may provide a "weigh {mass} batcher" system utilizing a weigh {mass} hopper equipped with load cells that determine the net amount of mix delivered from the weight {mass} hopper. An automated weigh {mass} printing system shall be provided to accurately print the weight {mass} of material delivered, the time, and the date for each t icket. All scales which determine the weight {mass} of the mix for pay purposes shall meet the requirements of Subarticle 109.01(h).
3.Hauling and Remixing Equipment.
a.Load Limitations. Reference is made to Article 105.12 concerning load limitations on hauling equipment. Wherever a Material Remixing Device is used, the following restrictions shall apply: • The device shall be empty while on a bridge. • The device shall be moved across a bridge without any other vehicles or equipment being on the bridge. • The device shall be moved on a bridge only within the limits of a lane and shall not be moved on the shoulder of a bridge. • The device shall move at a speed no greater than 5 miles {8 km} per hour without acceleration or deceleration.
b.Trucks. Each truck shall have a hole approximately 5/16 of an inch {8 mm} in diameter suitably placed in the side of the body , to allow for temperature measurement of the asphalt mix. Trucks used for hauling hot and warm mix asphalt mixtures shall have tight, clean, smooth metal beds that have been thinly coated with a minimum amount of approved asphalt release agent (List II -6, Hot Mix Asphalt Release Coating for Truck Beds, in the MSDSAR manual) to prevent the mixture from adhering to the beds. The use of gasoline, kerosen e, diesel or other volatile material is prohibited. Each truck shall be equipped with a tarpaulin that shall be used as needed to protect the mixture from adverse conditions. The tarpaulin shall be made of water repellent material, be of sufficient weight and strength to resist tearing and be in good condition with no holes or tears. The tarpaulin shall be large enough to cover the load. Mixture shall not leave the plant unless the load is covered when the following conditions exist: • when the air temperatu re is below 60 ° F {15 ° C}; • when hauling time exceeds 30 minutes; or
410.03 Construction Requirements.
• when threatening weather is present .
c.Material Remixing Device. When Pay Item 410 -H is included in the contract, a material remixing device shall be used for the placement of all asphalt layers except the following: • 327-E, Permeable Asphalt Treated Base (PATB); • A layer placed directly on top of PATB if the placement must be accomplished by operating the remixing device on the PATB. If a pay item is not shown on the Plans, the Contractor may use a material remixing device without compensation. A material remixing device shall not be placed on a Permeable Asphalt Treated Base. The material remixing device shall be capable of remixing plant mix between the trucks and the finished ma t. Plant mix shall be remixed in the device prior to being laid by the paver or spreader. The plant mix delivered by the material remixing device shall be a homogeneous, non - segregated mixture. Equipment known to accomplish this remixing operation and currently approved by ALDOT are listed below: Manufacturer Model Astec SB 3000 Blaw-Knox MC-330/TWIN PUG TUB ROADTEC Shuttlebuggy SB -1500, SB -2500 MTV-1000D, MTV -1000E Terex/Cedarapids CR 662 RM Weiler E1250, E1650, E2850 A material remixing device will not be required for the following situations: • temporary work of short duration, • bridge replacements having less than 1000 feet {300 m} of pavement at each end of a bridge, • acceleration and deceleration lanes less than 1000 feet {300 m} in length, • tapered sections, widening, patching, spot leveling, shoulders, crossovers, side street returns and other areas designated by the Engineer. • when placing a continuous leveling layer where the thickness of the layer is required to be transversely tapered (i .e. to correct cross slope) to a thickness less than twice the maximum aggregate size of the layer being placed. The Contractor shall use a hopper insert with a material remixing device if Pay Item 410 -H is included in the contract. On projects where Pay Item 410 -H is not included in the contract, use of a hopper insert is preferred, but not required.
4.Asphalt Pavers or Spreaders . Asphalt pavers or spreaders shall be self -contained and of sufficient size, power, and stability to receive, distribute, and strike off the asphalt material at rates and widths consistent with the specified typical section requirements and details shown on the plans and noted in Item 410.03(f)2. All asphalt pavers or spreaders used for mainline paving, including shoulders and in terchange ramps, shall be equipped with a full width vibratory, or other compactive type, screed. The augers used to move the material across the width of the screed shall extend within 1.5 feet {450 mm} of the edge of the screed. It will be permissible to use a hydraulically extendable strikeoff for paving turnouts and short sections of pavement including variable width sections and crossovers. When laying mixtures, the paver shall be capable of being operated at forward speeds consistent with satisfactor y laying of the mixture, providing a finished surface of the required evenness and texture without tearing, gouging, or shoving of the mixture. All asphalt paving machines shall be operated with automatic grade and slope controls unless otherwise directed by the Engineer. The automatic grade controls shall be a contact ski, a mobile stringline, or non -contact sonic averaging sensors. The effective length of these controls shall be a minimum of 24 feet {7.3 m}. In the event of a malfunction of the automatic control system, the spreading operation shall be discontinued after one hour until the equipment is repaired. If shown to be required on the plans, special attachments to the pavers and spreaders will be required to shape and finish the pavement.
410.03 Construction Requirements.
5.Compa ction Equipment. Compaction equipment shall be capable of compacting the mixture to the required density throughout the depth of the layer while it is still in a workable condition without damage to the material. The Contractor shall be responsible for the selection of the types and number of rollers to be used.
b.Daylight, Wet Weather, and Temperature Limitations .
1.Operations in Daylight. Placement and compaction operations shall be performed during daylight hours unless noted otherwise on the plans or directed otherwise by the Engineer. (The requirements for lighting for nighttime work are given in Suba rticle 104.04(a)).
2.Wet Weather. The mixture shall be laid only upon an approved underlying course, which is dry, and only when weather conditions are suitable. The Engineer may, however, permit work of this character to continue when overtaken by sudden rains, up to the amount which may be in transit from the plant at the time, provided the surface just ahead of the plac ement is swept clear of water an d the mixture is within the allowable temperature tolerances. The layer placed under such conditions shall be at the Contractor's risk and shall be removed and replaced by the Contractor without extra compensation should it prove unsatisfactory.
3.Cold We ather Restrictions. Hot mix asphalt (HMA) layers of 200 pounds per square yard {110 kg/m 2} or less shall not be placed when the surface or air temperature is below 40 ºF {4 ºC}; air temperature shall be 40 ºF {4 ºC} before the spreading operation is started. Spreading operations shall be stopped when the air temperature is below 45 ºF {7 ºC} and falling. For HMA layers over 200 pounds per square yard {110 kg/m 2}, the above temperature may be lowered 5 ° F {2 °C}. Unless otherwise stated in the plans and specifications, polymer modified HMA layers of 200 pounds per square yard {110 kg/m2} or less shall not be placed when the surface or air temperature is below 60 oF {15 oC}; for layers over 200 pounds per square yard {110 kg/m2}, the above temperature may be lowered 10 ° F {5 °C}. Warm mix asphalt (WMA) layers of 200 pounds per square yard {110 kg/m2} or less shall not be placed when the surface or air temperature is below 32 ºF {0 ºC}; air temperature shall be 32 ºF {0 ºC} before the spreading operation is started. Spreading operations shall be stopped when the air temperature is below 35 ºF {2 ºC} and falling. For WMA layers over 200 pounds per square yard {110 kg/m2}, the above temperature may be lowered 5 ° F {2 ° C}. Unless otherwise stated in the plans and specifications, polymer modified WMA layers of 200 pounds per square yard {110 kg/m2} or less shall not be placed when the surface or air temperature is below 50 oF {10 oC}; for layers over 200 pounds per square yard {110 kg/m2}, the above temperature may be lowered 10 ° F {5 °C}. With the exception of Section 420 "Polymer Modified Open Graded Friction Course" layers and any asphalt mixes containing RAS , the Contractor may place HMA and WMA layers at temperatures lower than the cold weather limits. The Contractor is warned that other factors such as wind speed and percent humidity may increase the heat loss from the HMA and WMA layers. All other requirements for the installation and quality of the HMA and WMA layers shall be applicable to th e work even when the restrictions against placement of the HMA and WMA during cold weather are not followed. The layers placed under such conditions shall be at the Contractor's risk and shall be removed and replaced without extra compensation if they are unacceptable. There will be no direct payment for additional costs associated with the placement of HMA and WMA during cold weather.
c.Preparation of Underlying Surface .
1.General . The underlying surface must be approved by the Engineer before the pla cement of a plant mix application will be allowed. The underlying surface, whether an old surface or a new surface, shall be thoroughly cleaned of all foreign or loose material and maintained in such condition in advance of the placement operations . Failur es in existing pavement or base shall be corrected, as noted in Item 410.03(c)2, in advance of the placement of an overlying layer. A prime coat, when required, shall be placed in accordance with Section 401. T ack coat shall be placed in accordance with Section 405.
410.03 Construction Requirements.
2.Patching . When patching of an existing surface is provided by the plans, the Engineer will examine the pavement surface and designate the area to be patched. The designated areas shall be trimmed to the depth of the unstable material as directed. The loose faulty material shall be picked up and removed from the area. The newly exposed patch area shall be cleaned and treated with prime or tack material as directed before placement of patching material. The hot and/or warm mix asphalt patch ing material shall be placed and compacted by methods approved by the Engineer until the patch area is filled to the elevation of the surrounding surface. Compaction of the patching material shall be to the degree that further consolidation of the patching material is not anticipated and is acceptable to the Engineer.
3.Leveling . When leveling of an existing pavement or base is provided by the plans, the surface shall be brought to required grade and cross section with plant mix material. The surface to be treated shall be prepared as noted herein and approved before placing the new material. The plant mix material shall be spread in accordance with the provisions of Item 410.03(f)2 and shall be compacted to the satisfaction of the Engineer . Leveling shall include the placement of asphalt plant mix layers to correct superevelation when directed.
4.Widening . When widening is provided by the plans, the widening shall be placed at the locations designated by the plans and/or as directed by the Engineer. The requirements for placing the widening shall be the same, as far as practical, as for the placing of the normal roadway. Compaction of the widening material shall be to the degree that further consolidation of the widening material is not anti cipated and is acceptable to the Engineer.
d.Preparation of Mixtures .
1.Liquid Asphalt Binder. The liquid asphalt binder material shall be heated in a manner that insures the even heating of the entire mass under efficient and positive control at all ti mes. Any liquid asphalt binder material which, in the opinion of the Engineer, has been damaged shall be rejected.
2.Aggregate .
a.Aggregate Used for Batch Mixing and Continuous Mixing Operations. All aggregates shall be dried so that the moisture content of the hot and warm mix asphalt at the point of sampling is less than 0.20 % by weight {mass} in accordance with ALDOT -130. The temperature of the aggregate at the dryer shall not exceed 600 ºF {315 ºC}. When more than two ingredients enter into the com position of the mineral aggregate, they shall be combined as directed. The aggregate, immediately after being heated, shall be screened into three or more sizes and conveyed into separate bins, ready for batching and mixing with liquid asphalt binder material. However, for mixes using aggregate of 1/2 inch {12.5 mm} maximum size, the number of bins may be reduced to two.
b.Aggregates for Dryer Drum Mixing Operations. Maintenance of a uniform aggregate gradation is essential for a dryer drum operation; henc e, caution and care shall be exercised in stockpiling of materials to avoid segregation.
3.Mixing.
a.Mixing Temperature. The mixing temperature of HMA and WMA shall be in accordance with the refineries’ recommendations, based upon the temperature- viscosity curve, and shall be adequate to produce a mixture in accordance with the specification requirements. The mixing temperature shall not exceed 350 ° F {177 °C}. The mixing temperature for HMA and WMA shall be continuously recorded and delivered to the Engineer on the next working day.
b.Batch Mixing. The dried mineral aggregate, and measured mineral filler when used, prepared as prescribed above, shall be combined in uniform batches by determining the weight {mass} of and conveying into the mixer the proportionate amounts of each aggregate required to meet the j ob mix formula.
410.03 Construction Requirements.
The largest size aggregate shall be introduced first, then smaller sizes progressively, with mineral filler last, or all mineral components may be added simultaneously. The mineral c omponents shall be thoroughly mixed. The required quantity of liquid asphalt binder material for each batch shall be measured by weight {mass} using scales or a liquid asphalt binder material metering device attached to the liquid asphalt binder material b ucket. After the mineral components have been mixed, the liquid asphalt binder material shall be added and the mixing continued for a period of at least 45 seconds, or longer if necessary to produce a homogeneous mixture. However, if a check by ASTM D 2489 (Ross Method) shows that 95% plus coating is obtained, a shorter mixing time will suffice. The Engineer may then give written permission for a change. Each batch must be kept separate throughout the weight {mass} determining and mixing operations. The mix ture shall be uniform in composition, free from lumps or balls of material containing an excess quantity of asphalt, or from pockets deficient in asphalt.
c.Continuous Mixing. Components shall be introduced and proportioned volumetrically by continuous methods utilizing equipment specified herein for continuous plants. Amounts of aggregate and liquid asphalt binder material entering the mixer, and the rate of travel through the mixer, shall be so coordinated that a uniform mixture of specified gradation and liquid asphalt binder content will be produced.
d.Dryer- Drum Mixing. Components shall be proportioned by weight {mass} as noted herein in Item 410.03(a)1 for this method of mixing. Amounts of aggregate and liquid asphalt binder material ent ering the mixer, and the rate of travel through the mixer, shall be so coordinated that a uniform mixture of specified gradation and liquid asphalt binder content will be produced. An anti -stripping agent may be required to insure adequate coating of the a ggregates, if so directed by the Engineer.
4.Recycled Mixtures.
a.New Aggregate Temperature. The new aggregate shall be super -heated to a temperature such that , when combined with the reclaimed material, the specified discharge temperature is produced; h owever, in no case shall the temperature of the new aggregate exceed 600 ° F {315 ° C}.
b.Mixing. The plant shall be designed and operated so that heat transfer will take place in the mixing unit without damage to, or vaporization of, the liquid asphalt bin der material. For batch type plants, a minimum dry mixing cycle of 15 seconds shall be required for the new aggregate and reclaimed material before introduction of the new liquid asphalt binder material. All environmental regulations shall be met as required by Article 107.22.
e.Transporting the Mixture . The mixture shall be transported in haul trucks meeting the requirements of Item 410.03(a)3. The equipment shall be in sufficient numbers to deliver the material to the roadbed without delay in the quanti ty required. Loads shall not be delivered too late in the day to be spread, compacted, and finished during daylight hours, unless nighttime work is allowed as shown on the plans or directed by the Engineer. Loads shall not be delivered at a temperature greater than 350 ° F {177 ° C} , or less than 220 °F {105 °C} without written permission of the State Materials and Tests Engineer.
f.Placing the Mixture .
1.Rate of Placement. The placement rate of plant mix will be specified by the plans; however, this rate may require correction to adjust for the compacted mix unit weight {density} as determined in the j ob mix formula design as outlined in Subarticle 410.02(b). The Engineer may direct in writing that the designated weight {mass} be increased or decreased in certain areas. It shall be the Contractor's responsibility to place and spread the material uniformly and compact it to such a thickness that will produce the specified rate, separately for each layer of base, binder, and surface, and to maintain a contin uing check on tonnage {mass} and yardage {area} throughout the day's operation to insure uniform specified rate. The unit for checking the average rate shall be approximately 5000 square yards {5000 m2} to the nearest even truck load. If the last check per formed in any day or any section of roadway is between 2000 and 5000 square yards {2000 and 5000 m2}, this section shall be classified as a unit; if less than 2000 square yards {2000 m2}, this section shall be added to the previous unit and the revised unit
410.03 Construction Requirements.
rechecked. When the initial day's operation is less than 2000 square yards {2000 m2}, this initial section will be carried over to subsequent days' operations to make a unit of approximately 5000 square yards {5000 m2}. In any unit checked, t he average rate shall not vary from the specified rate by more than 10 pounds per square yard {5 kg/m2} for layers of 225 pounds per square yard {120 kg/m2} or less, and 15 pounds per square yard {8 kg/m2} for layers greater than 225 pounds per square yard {120 kg/m2}. On the first applied layer of resurfacing where there is no required milling or leveling, this tolerance is increased to 15 pounds per square yard {8 kg/m2} for layers of 225 pounds per square yard {120kg/m2} or less, and 25 pounds per square yard {13 kg/m2} for layers greater than 225 pounds per square yard {120 kg/m2}. This tolerance is for providing leeway in equipment adjustment only. A consistent and uncorrected variation from the specified rate, even within this tolerance, will not be allowed without the Engineer's written approval. This tolerance does not apply to patching, leveling, and widening. If the average rate of any unit is found deficient by more than the above referenced tolerance, the Engineer will determine (1) whether the Co ntractor shall remove and replace the deficient unit without payment for the removal or the material removed, or (2) whether the Contractor may leave the deficient unit in place and cover it with a layer of the same mix of adjusted maximum size aggregate o f not less than 80 pounds per square yard {45 kg/m2} average. In case (2), the surface layer shall not be feather- edged at the end of the overlay layer, but a sufficient amount of the surface beyond the ends of the deficient unit shall be removed, to a nea t line across the pavement, to allow placing the full 80 pounds per square yard {45 kg/m2} and to make a joint that will meet the surface requirements. There will be no payment for any portion of the overlay needed to bring the total up to the designated a verage rate for that unit. If the average rate of any unit is found to exceed the above referenced tolerance, the tonnage {metric tonnage} in the unit that is in excess of the specified rate will be paid for as specified in Subarticle 410.09(a). Unless ot herwise provided in the following sections of these specifications, or shown on the plans, the average rate placed and compacted in one layer shall not exceed 350 pounds per square yard {200 kg/m 2} for base or binder layers, and 225 pounds per square yard {120 kg/m2} for surface layers. Where the amount to be placed exceeds these limits, it shall be placed and compacted in two or more approximately equal layers or as shown on the plans.
2.Spreading .
a.General. Spreading of the hot and warm mix asphalt mix ture shall be performed by equipment meeting the requirements of Item 410.03(a)4, except as noted in this Item. Approved specialized equipment may be employed to spread the hot and warm mix asphalt material where standard full scale equipment is impractica l due to size and irregularity of the area to be paved. Spreading operations shall be correlated with plant operations and hauling equipment such that the spreading operation, once begun, shall proceed at a speed as uniform and continuous as practical. The continual forward movement of the spreader requires the use of hauling vehicles capable of supplying the spreader with hot and warm mix asphalt material while the spreader is in motion. Repetitive interruptions or stopping of the spreader shall be cause f or the Engineer to suspend the work until the Contractor evaluates the cause of the stoppage and has provided a definite action plan for correction of the interruptions. Any interruption will require the thorough check of the area immediately under the spr eader and any variances shall be corrected immediately or the material removed and replaced, as directed, without additional compensation. Material placed in the spreader shall be immediately spread and screeded to a uniform depth so that the specified rate of the mixture required is achieved . Alignment of the outside edges of the pavement shall be controlled by preset control lines, and shall be finished in conformity with these controls. Any spreading operation, which cannot produce acceptable joints with in the surface tolerances and density requirements, shall be cause for requiring the Contractor to modify his operations to include additional spreading equipment.
b.Spreading by Motor Grader. For areas of a hot and warm mix asphalt plant mix surface inac cessible to the mechanical spreader, patching of pot holes and correcting failures in existing pavement, the plant mix may be
410.03 Construction Requirements.
dumped in low areas in the amounts directed, windrowed, spread, and compacted to bring the elevation and section to the desired level. If shown on the plans, the Contractor shall use a motor grader or a motor grader equipped with a dragbox to perform the spreading for the leveling operation. The motor grader shall be equipped with smooth faced tires. The dragbox, when required, shall be of sufficient size and weight {mass} to effectively shape and level the plant mix and shall be approved by the Engineer prior to use.
c.Spreading by Hand. For areas inaccessible to mechanical spreading equipment, and when patching potholes and minor pavement failures, hand spreading of the hot and warm mix asphalt mixture may be permitted. The mixture shall be distributed immediately into place by means of suitable tools and spread in a uniformly loose layer.
g.Compacting . As soon as the mixture has been spread and has set sufficiently to prevent undue cracking or shoving, rolling shall begin. A delay in th e initial rolling will not be tolerated and the initial or breakdown rolling should in general be performed by rolling longitudinally, beginning at the sides and proceeding toward the center of the surface. When initially constructing any leveling layers, the Contractor, as part of his QC plan, shall establish a rolling pattern using the nondestructive testing devices approved in Section 306 of the Specifications. The device shall either be calibrated to roadway cores or gage counts and shall be used to det ermine the rolling pattern producing maximum density. Contractor QC personnel shall be on site throughout each day to perform periodic checks and verify that the rolling pattern continually produces the maximum density that is achievable. When paving abuts a previously placed lane, the longitudinal joint shall be rolled in the first pass. On superelevated curves rolling shall begin at the low side and progress toward the high side. If any displacement occurs during rolling, it shall be corrected at once. To prevent adhesion of surface mixture to the rollers, the wheels shall be kept adequately moistened with water and a non-foaming detergent, but an excess of water will not be permitted. Adequate precaution shall be taken to prevent dropping of gasoline or oil on the pavement. In places inaccessible to a roller, compaction shall be obtained with hand or mechanical tampers that produce adequate pressure to obtain the required density. When the roller is in contact with a bridge deck, vibratory mode shall be turned off and the roller shall operate in static mode only. Throughout the process of compacting, tests for surface smoothness as required by Article 410.05 and density as required by Section 306 shall be made continuously.
h.Joints .
1.General . Placing of hot and warm mix asphalt paving layers shall be as continuous as possible. All joints shall be constructed in such a way as to provide a smooth, well –bonded, and sealed joint meeting the density and surface requirements of Articles 410.04 and 410.05. F ailure to meet requirements noted above shall be cause for ordering the removal and reconstruction of the joint without additional compensation. The contact surface of concrete structures shall be treated with a thin coat of liquid asphalt binder material, tack material, or the liquid asphalt binder material used in the mix, prior to construction of the joint. When directed by the Engineer, the same treatment noted above shall be used on cold asphalt joints.
2.Longitudinal . Longitudinal joints in the weari ng surface shall conform with the edges of proposed traffic lanes, insofar as practical. Any necessary longitudinal joints in underlying layers shall be offset so as to be at least 6 inches {150 mm} from the joint in the next overlying layer.
3.Transverse . Transverse joints shall be carefully constructed. Rollers shall not pass over the unprotected edge of the freshly laid mixture unless laying operations are to be discontinued. To facilitate the expeditious removal of the plant mix joint when laying opera tions are resumed, the Contractor shall place a heavy wrapping paper on the underlying surface across the joint and place plant mix on top of the paper.
410.04 Density Requirements.
Upon resumption of the work, a neat vertical joint shall be formed into the previously laid material to expose the full depth of the layer. The fresh mixture shall be raked and tamped to provide a well -bonded and sealed joint meeting surface and density requirements.
410.04 Density Requirements.
Density requirements shall be as specified in Table IV, Subart icle 410.08(e).
410.05 Surface and Edge Requirements.
a.Surface Smoothness Requirements .
1.General . Surface smoothness and roadway section will be checked by the use of string, Engineer's level, and straight edge. The Contractor shall furnish string, straightedges, and the necessary personnel to handle them under the supervision of the Engineer. Surface smoothness tests shall be made continuously during and immediately after rolling so that irregularities may be eliminated to the extent possibl e by rolling while the material is still workable; otherwise, deficiencies shall be corrected as provided in Article 410.06.
2.Perpendicular to Centerline of Roadway . The finished surface of all base, binder, and wearing surface layers shall not vary more than 1/4 of an inch {6 mm} from a 10 foot {3.0 m} straightedge placed perpendicular (at a right angle) to the centerline of the roadway anywhere on the surface. Unless shown otherwise on the plans , the slope shall not vary by more than 0.20 % from the required slope in any 10 foot {3.0 m} distance over which the slope is measured without the Engineer's written approval. (If, for example, a 2.0 % slope is required, the measured slope shall not be greater than 2.2 % or less than 1.8 %.)
3.Parallel to Centerline of Roadway . The surface shall not vary more than 1/4 of an inch {6 mm} from a 16 foot {4.8 m} straightedge placed parallel to the centerline anywhere on the surface. A 16 foot {4.8 m} rolling straightedge, equipped with marking capability, may b e used in lieu of the fixed straightedge if approved by the Engineer. The finished surface shall not vary more than 3/8 of an inch {9 mm} in any 25 foot {8 m} section from a taut string applied parallel to the surface at the following locations: 1 foot {30 0 mm} inside of the edges of pavement, at the centerline, and at other points designated by the Engineer. The variance from the designated grade shall not increase or decrease by more than 1/2 of an inch {12 mm} in 100 feet {30 m}.
b.Edge Requirements . Unless shown otherwise on the plans, surface, binder, and leveling pavement edges not confined by curbing or other structures may be lightly tamped behind the placement operation as a preventative measure against cracking and bulging during the rolling proc ess. This procedure shall also be required on the initial edge of a longitudinal cold joint. These edges shall be neatly shaped to line behind the breakdown roller and shall be trimmed as necessary after final rolling, to an accurately lined string or wire providing a maximum tolerance of 2 inches {50 mm} outside the theoretical edge of pavement, with a maximum variation from a true line of 1/2 of an inch {12 mm} in 10 feet {3 m} and a slope not flatter than 1:1. Edges that are distorted by rolling shall be corrected promptly.
c.Smoothness Requirements . The smoothness requirements and testing covered in this Subarticle shall apply for pay factor adjustments as indicated in the table below only if Item 410 -I Smoothness Te sting – Certified Inertial Profiler is included on the plans or in the proposal.
1.Testing Device .
a.Description. The testing device shall be an inertial profiler that satisfies the requirements of ALDOT- 448, “Evaluating Pavement Profiles,” including the portable storage device(s) referenced herein. Portable storage devices containing profile measurements shall become the property of the Department at the time the measurements are taken.
410.05 Surface and Edge Requirements.
b.Equipment Requiremen ts. The inertial profiler shall be a certified, non -contact, laser -based device capable of simultaneously measuring both wheelpaths meeting all the requirements of ALDOT- 448. Portable storage device(s) for the inertial profiler shall be furnished in suffic ient quantities for all calibration, test runs, and actual tests deemed necessary by the Engineer. Unless approved in advance by the Engineer, all portable storage devices provided by the Contractor will take the form of commonly available 2G USB flash dr ives.
2.Testing Procedure .
a.Description. The testing device shall be an inertial profiler that satisfies the requirements of ALDOT- 448, “Evaluating Pavement Profiles,” including the portable storage device(s) referenced herein. Portable storage devices containing profile measurements shall become the property of the Department at the time the measurements are taken. 410-I Smoothness Testing – Certified Inertial Profiler Open Graded Friction Course Layer Data Collection Required & Pay Factors Apply Wearing Surface Layer Data Collection Required & Pay Factors Apply Smoothness testing shall be performed and reported daily until the contractor demonstrates the ability to achieve a Mean Roughness Index (MRI) value of less than 65 in/mile. If the Contractor demonstrates the ability to achieve a MRI value of less than 65 in/mile then the Contractor may elect to perform and report the smoothness testing at a frequency he determines but not to exceed 5 working days production.
b.Smoothness Requireme nts. The results of the inertial profiler tests shall be evaluated by Department personnel as outlined in ALDOT -448. If a Mean Roughness Index (MRI) value of 90 inches per mile { 1.4 m/km} is exceeded in any test section of any daily paving operation, the paving operation will be suspended as soon as possible after results of the unacceptable test section are obtained. The paving will not be allowed to resume until corrective action is taken by the Contractor. When the MRI is more than 65 inches per mile { 1.0 m/km}, per section, a unit price reduction will be assessed. When the MRI is less than 45 inches per mile { 0.7 m/km} per section, a unit price increase will be added. The price adjustments are given in Table 1 . TABLE I Mean Roughness Index Inches/Mile/Section {meters /Kilometer/Section} Contract Price Adjustment Percent of Pavement Unit Bid Price Under 35 {Under 0.6} 105 35 to less than 45 {0.6 to less than 0.7} 105 – (MRI – 35)/2 {105 – (MRI – 0.6)/0.02 45 to less than 65 {0.7 to less than 1.0} 100 65 thru 90 {1.0 thru 1.4} 100 – (MRI – 65)/1.25 {100 – (MRI – 1.0)/0.02} Over 90 {Over 1.4} Unacceptable For Pay Item 410 -I, any price adjustment for smoothness considerations will be applied to the theoretical tonnage {metric tonnage}, calculated using the plan specified rate of placement, placed
410.06 Correction of Deficiencies and Defects.
in those sections testing under 40 in/mile, or more than 65 inches/mile {0.6 m/km, or more than 1.0 m/km} per section. There will be no payment greater than 100% for any section in which there were transverse joints that have been corrected by grinding per Article 410.06.
410.06 Correction of Deficiencies and Defects.
Deficiencies in surface smoothness as determined in Subarticle 410.05(a) shall be remedied t o the extent practicable by rolling while the material is still workable. Otherwise the layer shall be removed and replaced as necessary to obtain required smoothness. "Skin patching" of a surface layer to correct low areas or heating and scraping to correct high areas will not be permitted. Overlays of not less than 80 pounds per square yard {45 kg/m2} may be authorized by the Engineer for surface smoothness deficiencies provided all material in the overlay is without additional cost to the Department. Diamond grinding to correct transverse joints may be allowed at the sole discretion of the Engineer. Micro -milling or fine milling may be used to correct joints in underlying layers. Grinding shall not be used on an Open- Graded Friction Course. Slurry a nd residue from the grinding shall not be allowed to flow across travel lanes or into drainage facilities or adjacent bodies of water. A fog seal shall be applied over any grinding areas in a wearing surface. Placement of the fog seal shall be as directed by the Engineer. Deficiencies in thickness shall be remedied as specified in Item 410.03(f)1. All areas containing excessive or deficient amounts of liquid asphalt binder, all areas showing unacceptable segregation of materials, and all areas unbonded aft er rolling shall be removed and replaced at no cost to the Department. Unacceptable segregation of a hot and warm mix asphalt mat is defined as any area in which two six inch {150 mm} cores are taken and the average percent liquid asphalt binder content of the cores have an absolute difference greater than 0.50 percentage points of the design liquid asphalt binder content, or the combined gradation analysis of the two cores on selected sieves has an absolute difference greater than 10 percentage points fro m the j ob mix formula. All testing shall be in accordance with ALDOT- 389, "Evaluation of Segregated Areas in Hot Mix Asphalt Pavement." The location of all cores taken for segregation evaluation will be determined by the Department. All coring and traffic control required by ALDOT- 389 shall be conducted /supplied by the Contractor at no cost to the Department; however, the Contractor will be reimbursed $500.00 per core when core results are within tolerances and the coring operations require additional traff ic control. At any time that segregation is determined to be unacceptable, work shall be automatically suspended if positive corrective action is not taken by the Contractor to prevent further segregation in the mat. Upon suspension, the Contractor shall p lace a test section not to exceed 500 tons {500 metric tons} of the affected mixture for evaluation by the Engineer. However, if after a few loads it is apparent that the corrective actions were not adequate, work shall again be suspended and the segregate d areas evaluated in accordance with ALDOT -389. Likewise, if after 500 tons {500 metric tons} it is apparent that the problem has been solved, work will be allowed to continue. When correcting subsurface mixtures (base and binder layers), the removal and replacement may be limited to the actual defective areas or the full mat width within the limits of individual defective areas as directed by the Engineer. Removal and replacemen t of hot and warm mix asphalt wearing surface layers shall be a minimum of the full mat width and 10 feet {3 m} in length. All surface tolerance requirements shall apply to the corrected areas for both subsurface and surface mixes. Areas found deficient in density shall be removed and replaced or immediately re -rolled until density is acceptable. All work specified in this Article shall be performed without additional compensation.
410.07 Maintenance and Protection.
Sections of newly finished work shall be protected from all traffic until properly hardened. Maintenance shall include immediate repairs of any defects that may occur on the work; such repairs shall be repeated as often as necessary to maintain the work in a continuously satisfactory condition . The Contractor shall be responsible for the protection of the work and protection of any traffic using the work. No additional compensation will be paid for maintenance and protection.
410.08 Method of Measurement.
a.General . The accepted quantity of h ot and warm mix asphalt plant mix used as directed will be measured in tons of 2000 pounds {metric tons} in accordance with the following:
410.08 Method of Measurement.
When the laboratory compacted density as determined in the j ob mix formula design exceeds 158 pounds per cubic foot { 2530 kg/m3}, the actual total tonnage {metric tonnage} of mix placed will be adjusted for pay purposes in accordance with the following formula (this shall not apply to Section 327 PATB and Section 420 OGFC): y = 158 c / a { y = 2530 c / a}, where y = total tonnage {metric tonnage} of plant mix for pay purposes; c = actual tonnage {metric tonnage} of plant mix measured and placed, except items subject to pay factor adjustment under the QC/QA provisions. On items subject to pay factor adjustment, t he adjusted tonnage {metric tonnage} (after pay factor adjustment) will be used; a = laboratory compacted mix unit weight in pounds per cubic foot {density in kilograms per cubic meter} as shown in the j ob mix formula. No adjustments to the actual total tonnage {metric tonnage} placed will be made where the laboratory compacted mix density is below 158 pounds per cubic foot {2530 kg/m3}. No adjustments to the actual tonnage {metric tonnage} placed will be made when the use of lightweight aggregate (expand ed clay or shale) is designated. For determining weight {mass}, each load of hot and warm mix asphalt mixture shall have its weight {mass} determined on approved certified scales, as specified in Article 109.01, furnished by the Contractor without direct c ompensation. The weight {mass} measurement shall include all components of the mixture. No deductions will be made for any of the components, including the liquid asphalt binder material, contained in the mixture. The laboratory compacted density requireme nts for OGFC are given in Section 420. Section 327 PATB does not have a laboratory compacted density requirement because a layer thickness (typically 4 inches {100 mm}) is required instead of a rate of placement.
b.Acceptance of the Mixture . The hot and warm mix asphalt mixture will be evaluated at the plant on a LOT to LOT basis. The material will be tested for acceptance in accordance with the provisions of Section 106 and the following requirements. However, any load or loads of mixture, which, in th e opinion of the Engineer, are obviously unacceptable, will be rejected for use in the work. The Contractor shall control all operations in the handling, preparation, and mixing of the hot and warm mix asphalt plant mix so that the percent liquid asphalt b inder and voids in laboratory compacted samples or gradation will meet the approved j ob mix formula within the tolerances shown in Tables II, III, and VI for the 1.00 pay factor. In recognition of the fact that the drying and screening operations may gene rate additional dust over that shown in the approved mix design, the Contractor's attention is directed to the fact that the dust must be controlled in order to control VMA and voids in the total mix. Acceptance of the mixture will be in accordance with Su barticle 106.09(c). LOT pay factors for asphalt content and air voids will be determined from Table II for Section 423 mixes and from Table III for a Section 424 mix after the requirements of Item 106.09(c)3 are satisfied. LOT pay factors for asphalt conte nt will be determined from the top half of Table II for Section 327 and 420 mixes after the requirements of Item 106.09(c)3 are satisfied. Air voids are not a pay factor for Section 327 and 420 mixes. Gradation is shown as a pay factor for Section 420 mixe s in Table VI. The pay factor values determined for each sieve noted in Table VI will be averaged. This average will then be compared to the asphalt content pay factor. The lowest of these two pay factors will be applied to the mix. Calculations for the a cceptance test results for asphalt content and voids in total mix shall be carried to the thousandths (0.001) and rounded to the nearest hundredth (0.01). Calculations for averages shall be carried to the thousandths (0.001) and rounded to the nearest hundredth (0.01) in accordance with ASTM E 29 rules of rounding. LOT pay factors will be calculated to the nearest hundredth (0.01). Payment for Section 327 and 423 mixes will be on the basis of Table II Acceptance Schedule for Payment. Payment for a Section 424 mix will be on the basis of Table III Acceptance Schedule for Payment. Payment for Section 420 mixes will be on the basis of Table II and Table VI.
c.Suspension and Voluntary Termination of Lots . The production process will be considered out of control when any individual test result (asphalt content, gradation, or air voids) from a LOT has a pay factor equal to 0.80 computed from the "1 Test" row in Table II, the “1 Test” row in Table III, or the “1 Test” column in Table VI, whichever is appropr iate. When gradation is a pay factor, a 0.80 result for an individual screen (before averaging)
410.08 Method of Measurement.
is considered out of control. If any single gradation for the 327 mixes falls outside of the gradation band shown in Section 327 the process is considered out o f control. When this happens, production shall be suspended. If mix from the suspended LOT is contained in storage/surge bins, that mix will be considered part of the suspended LOT, and shall not be placed on any State project. When production is suspende d as described above, or when the contractor voluntarily terminates a lot, production shall not be re -started until after all of the following has been accomplished:
1.the Contractor shall notify the Project Manager immediately that the process is out of control, or that the LOT has been terminated voluntarily, and that production has been suspended;
2.the Contractor shall determine the appropriate adjustments to make in order to bring the process under control and inform the Project Manager in writing of these adjustments;
3.after adjustments, the Contractor shall produce a trial batch of mix (approximately 25 to 35 tons {25 to 35 metric tons}) a nd test for control characteristics (asphalt content, gradation, and air voids);
4.adjustments, trial batches, and tests shall be repeated as many times as necessary until pay factors for asphalt content, gradation, and air voids equal 1.00, minimum, at which time production may be re -started. Mix utilized as a trial batch shall not be used on the project.
d.Acceptance Schedule of Payment for Asphalt Plant Mix Characteristics . TABLE II SECTION 327 MIXES** SECTION 420 MIXES (OPEN GRADED FRICTION COU RSE)** SECTION 423 MIXES (STONE MATRIX ASPHALT) ACCEPTANCE SCHEDULE OF PAYMENT FOR ASPHALT PLANT MIX CHARACTERISTICS Arithmetic Average of the Absolute Values of Deviations of the LOT Acceptance Tests From Job Mix Formula Values Asphalt Content LOT Pay Factor -> 1.02 1.00 0.98 0.95 0.90 0.80* 1 Test - 0.00-0.48 0.49-0.51 0.52-0.57 0.58-0.66 Over 0.66 2 Tests - 0.00-0.34 0.35-0.36 0.37-0.40 0.41-0.47 Over 0.47 3 Tests - 0.00-0.28 0.29-0.29 0.30-0.33 0.34-0.38 Over 0.38 4 Tests 0.00-0.14 0.15-0.24 0.25-0.26 0.27-0.28 0.29-0.33 Over 0.33 Voids in Total Mix (Lab. Compacted Samples) LOT Pay Factor -> 1.02 1.00 0.98 0.95 0.90 0.80* 1 Test - 0.00-1.50 1.51-1.62 1.63-1.80 1.81-2.10 Over 2.10 2 Tests - 0.00-1.06 1.07-1.15 1.16-1.27 1.28-1.48 Over 1.48 3 Tests - 0.00-0.87 0.88-0.94 0.95-1.04 1.05-1.21 Over 1.21 4 Tests 0.00-0.45 0.46-0.75 0.76-0.81 0.82-0.90 0.91-1.05 Over 1.05 * If approved by the Department, the Contractor may accept the indicated LOT partial pay. The Department may require removal and replacement. If the LOT pay factor is greater than 0.80, the Contractor has the option to remove at no cost to the Department and to replace at contract unit bid price rather than accepting the reduced LO T payment. ** The Acceptance Schedule of Payment for “Voids in Total Mix” will not apply to the 327 and 420 mixes
410.08 Method of Measurement.
TABLE III SECTION 424 MIXES (SUPERPAVE) ACCEPTANCE SCHEDULE OF PAYMENT FOR ASPHALT PLANT MIX CHARACTERISTICS Arithmetic Average of the Absolute Values of Deviations of the LOT Acceptance Tests From Job Mix Formula Values Asphalt Content LOT Pay Factor - > 1.02 1.00 0.98 0.95 0.90 0.80* 1 Test - 0.00-0.62 0.63-0.68 0.69-0.75 0.76-0.88 Over 0.88 2 Tests - 0.00-0.44 0.45-0.48 0.49-0.53 0.54-0.62 Over 0.62 3 Tests - 0.00-0.36 0.37-0.39 0.40-0.43 0.44-0.51 Over 0.51 4 Tests 0.00-0.19 0.20-0.31 0.32-0.34 0.35-0.38 0.39-0.44 Over 0.44 Voids in Total Mix (Lab. Compacted Samples) LOT Pay Factor - > 1.02 1.00 0.98 0.95 0.90 0.80* 1 Test - 0.00-2.50 2.51-2.70 2.71-3.00 3.01-3.50 Over 3.50 2 Tests - 0.00-1.77 1.78-1.91 1.92-2.12 2.13-2.47 Over 2.47 3 Tests - 0.00-1.44 1.45-1.56 1.57-1.73 1.74-2.02 Over 2.02 4 Tests 0.00-0.75 0.76-1.25 1.26-1.35 1.36-1.50 1.51-1.75 Over 1.75 * If approved by the Department, the Contractor may accept the indicated LOT partial pay. The Department may require removal and replacement. If the LOT pay factor is greater than 0.80, the Contractor has the option to rem ove at no cost to the Department and to replace at contract unit bid price rather than accepting the reduced LOT payment.
410.08 Method of Measurement.
TABLE VI SECTION 420 MIXES (OPEN GRADED FRICTION COURSE) ACCEPTANCE SCHEDULE OF PAYMENT FOR ASPHALT PLANT MIX CHARACTERISTICS Arithmetic Average of the Absolute Values of Deviations of the LOT Acceptance Tests From Job Mix Formula Values Gradation 3/8" {9.5 mm} Sieve LOT Pay Factor 1 Test 2 Tests 3 Tests 4 Tests 1.02 - - - 0.00 – 3.60 1.00 0.00 – 12.00 0.00 – 8.48 0.00 – 6.93 3.61 – 6.00 0.98 12.01 – 12.96 8.49 – 9.16 6.94 – 7.48 6.01 – 6.48 0.95 12.97 – 14.40 9.17 – 10.18 7.49 – 8.31 6.49 – 7.20 0.90 14.41 – 16.80 10.19 – 11.88 8.32 – 9.70 7.21 – 8.40 0.80* Over 16.80 Over 11.88 Over 9.70 Over 8.40 Gradation No. 8 {2.36 mm} Sieve LOT Pay Factor 1 Test 2 Tests 3 Tests 4 Tests 1.02 - - - 0.00 – 2.40 1.00 0.00 – 8.00 0.00 – 5.66 0.00 – 4.62 2.41 – 4.00 0.98 8.01 – 8.64 5.67 – 6.11 4.63 – 4.99 4.01 – 4.32 0.95 8.65 – 9.60 6.12 – 6.79 5.00 – 5.54 4.33 – 4.80 0.90 9.61 – 11.20 6.80 – 7.92 5.55 – 6.47 4.81 – 5.60 0.80* Over 11.20 Over 7.92 Over 6.47 Over 5.60 The comparison value for ALDOT and Contractor testing for the 3/8" {9.5 mm} and No. 8 {2.36 mm} sieves is +/ - 2.0%. * If approved by the Department, the Contractor may accept the indicated LOT partial pay. The Department may require removal and replacement. If the LOT pay factor is greater than 0.80, the Contractor has the option to remove at no cost to the Department and to replace at contract unit bid price rather than accepting the reduced LOT payment.
e.Acceptance of the Roadway Density. For paving that is not mainline paving (paving for patching, widening, and crossovers and leveling), in-place density pay factors will not be applied. For mainline paving (including shoulders, ramps, and acceleration/deceleration lanes), in -place density p ay factors will be applied as specified herein unless otherwise noted on the plans or in the specifications. After the hot and/or warm mix asphalt mixture has been placed and compacted, it shall be evaluated for density. A core for mat density determinati on shall be taken by the Contractor on each 3000 foot {900 m} segment of roadway lane of asphalt mixture placed. The location of each test will be designated by the Department. The core shall meet a minimum thickness for use in determining the roadway dens ity. If the core’s average thickness in inches {millimeters} is not at least 0.008 times the rate in pounds per square yard {0.375 times the rate in kilograms per square meter}, another core shall be taken (as close a practical to the original location) w here the Engineer believes the pavement is thick enough for roadway density determination. The core’s average thickness shall be determined by measuring the core’s thickness at six equidistant locations around the circumference of the core. The Departmen t will take immediate possession of the core and will make a density determination of the core in accordance with AASHTO T 166, Method A. The density values of the cores will be used to compute the pay factor for that sublot. Testing locations will be sele cted with the random number method outlined in ALDOT -210. Contractors are allowed, but not required, to take cores anywhere, anytime for quality control. This includes taking cores from the wearing layer. The contractor must have the permission of the Eng ineer to take cores from a PATB (327) or OGFC (420) mix. All core holes shall be promptly repaired at the contractor’s expense. For purposes of evaluation, a LOT will be as defined in Item 106.09(c)1. A SUBLOT for evaluation of density will be equal to 12,000 feet {3600 m} (4 test results) or fraction of a 12,000 foot {3600 m} length as applicable. For instance, a 27,000 foot {8100 m} LOT would be divided into two 12,000 foot {3600 m} SUBLOTS and one 3000 foot {900 m} SUBLOT. The in -place density will be expressed as a percentage of the theoretical maximum density (TMD) of the mix with the following relationship:
410.08 Method of Measurement.
% TMD = In Place Density X 100 Maximum Mix Density Maximum mix density is equated to maximum mix specific gravity as measured with AASHTO T 209, Flask determination with dry back. The maximum mix specific gravity used will be the average of the values from the four most recent determinations using Contractor data. The appropriate pay factor for each SUBLOT will be determined from Tab le IV for the appropriate number of test results. The pay factor for the LOT will be determined by computing the weighted average of the SUBLOTS: LOT Pay Factor (PF) = PF SUBLOT 1 (Length SUBLOT 1) + PF SUBLOT 2 (Length SUBLOT 2) + … Length SUBLOT 1 + Length SUBLOT 2 + … Calculations for the acceptance test results for in -place density will be carried to the hundredths (0.01) and rounded to the nearest tenth (0.1). LOT and SUBLOT pay factor calculations will be carried to the thousandths (0.001) and rounded to the nearest hundredth (0.01) in accordance with ASTM E 29 rules of rounding. The low rates of placement at which minimum density does not apply are given in Section 306. Density pay factors will not be applied to pavement layers placed at these rates. TABLE IV ACCEPTANCE SCHEDULE OF PAYMENT FOR IN -PLACE DENSITY SECTION 423 MIXES (STONE MATRIX ASPHALT) Characteristic SUBLOT PAY FACTOR Arithmetic Average of the Absolute Values of Deviations of SUBLOT Acceptance Tests From Target** 1 Test 2 Tests 3 Tests 4 Tests In-Place Density 1.02 0.00 - 2.00 0.00 - 1.41 0.00 - 1.15 0.00 - 1.00 1.00 2.01 - 3.33 1.42 - 2.36 1.16 - 1.92 1.01 - 1.67 0.98 3.34 - 3.60 2.37 - 2.55 1.93 - 2.08 1.68 - 1.80 0.95 3.61 - 4.00 2.56 - 2.83 2.09 - 2.31 1.81 - 2.00 0.90 4.01 - 4.67 2.84 - 3.30 2.32 - 2.69 2.01 - 2.33 0.80* Over 4.67 Over 3.30 Over 2.69 Over 2.33 SECTION 424 MIXES (SUPERPAVE) Characteristic SUBLOT PAY FACTOR Arithmetic Average of the Absolute Values of Deviations of SUBLOT Acceptance Tests From Target** 1 Test 2 Tests 3 Tests 4 Tests In-Place Density 1.02 0.0-2.25 0.0-1.59 0.0-1.30 0.0-1.12 1.00 2.26-3.75 1.60-2.65 1.31-2.17 1.13-1.88 0.98 3.76-4.05 2.66-2.86 2.18-2.34 1.89-2.02 0.95 4.06-4.50 2.87-3.18 2.35-2.60 2.03-2.25 0.90 4.51-5.25 3.19-3.71 2.61-3.03 2.26-2.62 0.80* Over 5.25 over 3.71 over 3.03 Over 2.62 * If approved by the Department, the Contractor may accept the indicated partial SUBLOT pay. The Department may require removal and replacement. The Contractor has the option to remove at no cost to the Department and replace at contract unit bid price rather than accepting the reduced SUBLOT payment. ** Target density shall be 94.0 % of the theoretical maximum density for all mixes except for: - the range of placement rates given in Item 306.03(g)3 ( 140 pounds per square yard or greater {76 kg per square meter or greater} and less than 200 pounds per square yard {109 kg per square meter} over surface treatments) the target density shall be 92.0 % and; - ESAL Range A and B mixes where the Contractor demonstrates and explains in writing why 94 % of the theoretical maximum density cannot be achieved and the Engineer informs the Contractor by written notification that the target density can be reduced to 93 % or 92 %.
410.09 Basis of Payment.
TABLE V COMPARISON OF ALDOT AND CONTRACTOR TESTING TEST ACCEPTABLE ASPHALT CONTENT ± 0.30 % AIR VOIDS ± 0.50 % GRADATION * See Table VI * Gradations given in Articles 327.02 and 420.02.
f.Tack Coat . Tack coat liquid asphalt material will be measured and paid for as specified in Section 405.
g.Wasted and Excess Materials Applied . Deductions in measurement will be made for all material wasted or lost due to negligence of the Contractor or applied beyond the limits of the work.
h.Material Remixing Device . The number of material remixing devi ces measured for payment will be the number of units approved by the Engineer for use. These devices will be measured per each device.
i.Certified Inertial Profiler. The number of certified inertial profilers measured for payment will be the actual number of units ordered and accepted.
410.09 Basis of Payment.
a.Unit Price Coverage . Compensation for plant mix material, measured as provided above, will be made on a tonnage {metric tonnage} basis and the contract unit price per ton {metric ton} for each i ndividual item shall be full compensation for construction of the hot and warm mix asphalt plant mix layer complete in place on the roadbed as specified or directed, including all materials, procurement, handling, hauling, and processing cost, and includes all equipment, tools, labor, and incidentals required to complete the work. Unless otherwise covered by a separate pay item, the cost of excavation for patching and widening, compacting the subgrade, backfilling, spreading, or disposing of excess excavated material, removal and disposal of old pavement, removal and resetting of roadway signs and mailboxes, and removal and disposal of pavement markers shall be subsidiary obligations of the associated plant mix pay item, and no additional payment will be mad e for performing the work. No payment will be made for unacceptable material; for material needed to overlay layers deficient in thickness; for material used in replacing defective or condemned construction; for material wasted in handling, hauling, or oth erwise; or for maintaining the work. When the average rate of placement is found to exceed the tolerance given in Item 410.03(f)1., the tonnage {metric tonnage} placed above the specified rate in that unit will be paid for at 50 percent of the contract uni t price. This reduction will not be applied to patching, leveling, and widening. Smoothness testing, measured with a certified inertial profiler as noted above, will be paid for at the contract unit bid price which shall be full compensation for furnishin g the inertial profiler and portable storage device(s) and includes all equipment, tools, labor, calibration, maintenance, services, supplies, and incidentals necessary to complete these items of work. The number of approved remixing devices, measured as n oted above, will be paid for at the contract unit bid price. This price shall be full compensation for furnishing the vehicles and shall include all equipment, tools, labor, calibration, maintenance, services, operator, and all other items necessary to fur nish and operate the vehicles.
b.Payment will be made under Item No .: See Appropriate Section for Type of Plant Mix Involved. 410-H Material Remixing Device - per Each 410-I Smoothness Testing - Certified Inertial Profiler -per Each
420.02 Materials.
SECTION 420 POLYME R MODIFIED OPEN GRADED FRICTION COURSE
420.01 Description.
The work covered by this Section shall consist of constructing a hot mixed, hot laid polymer modified open graded friction course wearing layer generally placed on an existing pavement. The typic al cross section and the average weight per square yard will be shown on the plans. Requirements for all hot mix asphalt pavements as specified in Section 410 are applicable to this Section, subject to any exceptions contained herein. Quality Control/Quali ty Assurance (QC/QA) requirements as specified in Section 106 are applicable to this Section, subject to any exceptions contained herein.
420.02 Materials.
The materials furnished for use shall comply with the requirements of Section 410 and the following:
a.Aggregates . The aggregate shall be limited to 100% crushed aggregates of the following: granite, quarried quartzite, slag, sandstone or manufactured lightweight aggregate, all of which shall be from approved sources and meet the appropriate requirements of Sections 801 and 802. However, if additional dust (- 200 {- 75 µm} material) is needed, mineral filler (meeting the requirements of Section 805) or agricultural limestone may be used. If agricultural limestone is used, it shall meet the requirements of ASTM C 602, Standard Specification for Agricultural Liming Materials, for Class E agricultural limestone, so that a minimum of 80.0 % of the material will pass the No. 8 {2.35 mm} sieve and 25.0 % will pass the No. 60 {0.250 mm} sieve. In addi tion, a minimum of 5.0 % will pass the No. 200 {75 µm} sieve. No more than 10.0 % agricultural limestone shall be used. The aggregate shall be combined into a total blend that will produce an acceptable job mix within the gradation limits shown in the following table. The blend shall be made from at least two stockpiles of different gradations. At least 10% of the blend sha ll be taken from each stockpile. AGGREGATE GRADATION FOR OPEN GRADED FRICTION COURSE Sieve (Square Mesh Type) Percent Passing By Weight {Mass} 3/4 inch {19.0 mm} 100 1/2 inch {12.5 mm} 85 - 100 3/8 inch {9.5 mm} 55 – 65 No. 4 {4.75 mm} 10 - 25 No. 8 {2.36 mm} 5 - 10 No. 200 {75 µm} 2 - 4 As stated in Article 410.02 no RAP or RAS is Allowed .
b.Liquid Asphalt Binder . The liquid binder shall be a polymer modified PG 76 -22 meeting the requirements of Section 804. The proportion of liquid asphalt binder to total sample by weight {mass} shall be 6.0 % to 9.0 %. The exact proportion shall be fixed by the job mix formula. Additives or modifiers shall be used to prevent stripping of liquid asphalt binder. These additives or modifiers shall be furnished and used at no additional cost to the State.
c.Polymer . The polymer additive shall meet the requirements of Section 811.
d.Liquid Asphalt Binder Draindown . A fiber stabilizer or Evotherm 3G meeting the requirements given in Section 410 shall be incorporated into the mix to produce a maximum liquid asphalt binder cement draindown of 0.30 % or less when tested at 325°F {163°C} and 350°F {176°C} in accordance with AASHTO T305. The fiber shall be blended into the mix in accordance with the requirements given in Section 410.
Source: Alabama Standard Specifications for Highway Construction, 2022 Edition. Pages 207–229 of 934.