MDOT SHA Section 504: Asphalt Pavement

— ASPHALT PAVEMENT CATEGORY 500 PAVING

504.01DESCRIPTION

Construct Asphalt Pavement.

504.02MATERIALS

Performance Graded Asphalt Binders 904.02 Tack Coat 904.03 Asphalt Mixes 904.04 Crack Sealer 911.01 Production Plants Section 915

504.03CONSTRUCTION

Quality Control Plan. Submit a Plant Quality Control Plan and a Field Quality Control Plan

(QCP)at least 30 days prior to placement of any asphalt pavement. Submit the Plant QCP to the

Office of Materials Technology (OMT) for approval. Submit the Field QCP to the District Engineer for approval. The Plans shall contain a statistically based procedure of random sampling and show methods proposed to control the equipment, materials, production, and paving operations. Discuss the QCP requirements in the pre-construction, pre-pave and progress meetings. The Plant and Field QCP shall contain:

(a)Name and location of asphalt production plants,

(b)Laboratory and field personnel qualifications,

(c)Inspection and record keeping methods, and

(d)Minimum frequencies of sampling and testing.

Use the Quality Control Plans for Plants Template to address all requirements necessary for plant quality control and plant approval. 624 — ASPHALT PAVEMENT Corrective actions will be taken for unsatisfactory construction practices and deviations from the Contract Documents. Plan Administrator and Certified Technicians. The QCPs shall designate a Plan Administrator who shall have full authority to institute any action necessary for the successful implementation of the Plan. The Plan Administrator may supervise the QCP on more than one project if that person can contact the job site within one hour after being notified. The QCP shall also designate a Certified Asphalt Plant Technician – Level 2, a Certified Asphalt Field Technician, a Certified Inertial Profiler Operator, a Certified Asphalt Plant Technician – Level 1, or Trainee Technicians according to the Mid-Atlantic Region Technician Certification Program (MARTCP) and the Maryland Technician Certification Program. A Certified Plant Technician shall be present at the plant during asphalt production and shipment unless otherwise approved in the Plant QCP. The technician shall perform quality control sampling, testing and documentation as specified. A Certified Field Technician shall be present at the job site unless otherwise approved in the Field QCP. The technician shall be responsible for the required field quality control sampling and testing. Deviations from the QCP shall be cause for immediate suspension of production and paving operations. The Certified Technicians shall perform sampling for quality control, quality assurance, acceptance, split sampling, and verification. Submit quality control test results to the Engineer. MARTCP-Certified Technicians found deficient in their duties will have their certification(s) rescinded, as determined. Replace the deficient technician with a certified technician before resuming production and paving operations. Records. Maintain complete records of sampling, testing, corrective actions and quality control inspection results. Provide copies of the reports upon request. Maintain linear control charts or use other types of control charts (such as standard deviation or range), as approved. Control charts may be maintained by production, by mix, or by mix per project. Maintain the control charts in the quality control laboratory per the QCP. The control charts shall identify the mix design number, each test result, and the upper and lower limits specified for each test. Retain all original Quality Control worksheets for five years. Quality Assurance (QA). The Administration will perform independent QA sampling, testing and inspections. QA consists of the following:

(a)Periodically observe the performance of Quality Control (QC) or QA testing,

(b)Monitoring control charts,

(c)Directing the sampling of mixes behind the paver prior to compaction,

625 — ASPHALT PAVEMENT

(d)Directing the sampling of mixes at the plant site,

(e)Directing the sampling of cores taken from the compacted pavement,

(f)Monitoring conformance with the approved QCP(s), and

(g)Quality control sampling and testing procedures and quality control sampling and

testing equipment will be evaluated according to the Independent Assurance (IA) program.

.01 Equipment. All production and paving equipment will be subject to approval. Ensure

the plant is ready for inspection as specified in 915.01.02. Hauling Units. Refer to 915.02(f). Pavers. Pavers shall be equipped with a means of preventing the segregation of the coarse aggregate particles when moving the mix to the paver augers. The means and methods used may consist of chain curtains, deflector plates, or other such devices, or any combination of these according to the manufacturer’s recommendations. Demonstrate that modifications to the paving equipment have been implemented on all pavers prior to use on the project. Use a self-contained, self-propelled unit for mainline paving. Inspection and approval will be based upon the manufacturer's recommendations. The paver shall:

(a)Produce a finished surface of the required smoothness and texture without tearing,

shoving, or gouging the mix.

(b)Be operated in a manner which delivers a homogeneous mix the full width of the

pavement.

(c)Have automatic controls capable of maintaining the grade and transverse slope within

the required tolerances set forth in the contract documents.

(d)Use auger extensions to maintain a distance no greater than 18 in. from the end of the

auger to the end gate when screed extensions are used. Provide reference lines or other approved markings to control the horizontal alignment. Manual operation will be permitted to make grade changes for constructing irregularly shaped and minor areas. The equipment may be operated manually for the remainder of the workday if a malfunction of any automatic control occurs, as directed. Safety Edge Magnetic Protractor. Safety edge magnetic protractor shall have increments of 0 degrees to 90 degrees in four quadrants, with a minimum 4 in. lens diameter and two level vials. 626 — ASPHALT PAVEMENT Rollers. Rollers shall be self-propelled, reversible, and steel wheeled or pneumatic tired. Inspect all rollers and present them for approval before use. Rollers shall be operated:

(a)In conformance with the manufacturer’s recommendations.

(b)In a manner that does not damage the pavement.

(c)In a manner that delivers the optimal combination of density and ride requirements.

(d)In a manner that protects bridge decks. Do not use rollers in vibratory mode when

paving bridge decks.

.02 Weather Restrictions. Place mixes used as the final surface when the ambient air and

surface temperatures are at least 40 F. Ensure that surfaces to be paved are clean and dry before paving, as approved.

(a)Place mixes used as intermediate and base layers when the ambient air and surface

temperatures are at least 32 F.

(b)Place polymer-modified surface mixes when the ambient air and surface temperatures

are at least 50 F.

(c)When it begins raining while the work is underway, material en route from the plant

may be used at risk.

(d)The Administration reserves the right to perform any testing necessary to ensure the

quality of the pavement.

(e)All additional testing and associated costs, including maintenance of traffic, will be at

no cost. If material placement is halted due to weather conditions, waste all material en route at no additional cost. Do not place asphalt on a frozen graded aggregate base.

.03 Foundation Preparation. Construct the foundation as specified prior to paving. Place

crack seal and mastic as specified in Section 510. Remove excess crack sealer and patch material before paving over existing pavement. Clean, tack coat, fill with asphalt, and tamp spalls and potholes before paving. Adjust to grade manholes, valve boxes, inlets, and other construction appurtenances within the area to be paved as directed.

.04 Tack Coat. Ensure the surface is dry and thoroughly cleaned by a power broom and/or

air blowing prior to application. Apply the tack coat by uniformly covering the entire surface to be paved using an application rate of 0.04 gal/yd 2 to 0.10 gal/yd 2 or as directed by the Contract documents. Allow the tack coat time to thoroughly break and set. 627 — ASPHALT PAVEMENT

.05 Non-Tracking Tack Coat (NTTC). The Manufacturer shall supply a QCP for the

NTTC detailing the handling and application procedures according to PP71-11, and test results from an independent, accredited laboratory for shear and tensile strength.

(a)Sample the NTTC as directed and submit to OMT’s Asphalt Technology Division. All

samples will be tested against the manufacturer’s specifications. Material out of compliance will not be accepted for use.

(b)Use equipment to heat and apply the NTTC at an application temperature range that

conforms to the manufacturer’s recommendations. Apply the NTTC as specified in

.02 and as directed

(c)Apply the NTTC uniformly with a pressure distributor. Use hand spraying equipment

only in areas inaccessible to the pressure distributor. Apply the NTTC using an application rate of 0.05 gal/yd 2 to 0.10 gal/yd 2 and do not dilute with water. The quantity, rate of application, temperature, and areas to be tacked shall be approved prior to application.

(d)Do not clean or discharge the tack coat distributor into ditches, onto shoulders or along

the right of way. Park the distributor so the spray bar will not drip NTTC onto the surface of the traveled pavement.

(e)Exclude all traffic from sections treated with NTTC until the tack has cured and will no

longer track onto adjacent non-treated areas. Adjacent pavement surfaces shall show minimal visible evidence and pavement markings shall show no visible evidence of tracking.

.06 Asphalt Placement. Delivery and placement of the asphalt should be continuous

Place the asphalt while the temperature is at least 225 F, or as specified in the Field QCP. Place the asphalt with a paver that conforms to 504.03.01. Do not broadcast loose mix over the new surface.

.07 Compaction. Roll the asphalt immediately after placement and compact to the proper

in-place density and ride smoothness. Incentive or disincentive price adjustment for density will be as specified in 504.04.02. Use steel wheel rollers for the first rolling of all joints and edges, the initial breakdown rolling, and the finish rolling. Use a power driven trench roller when base widening is too narrow to permit the use of conventional rollers. Construct an earth berm or shoulder against the loose asphalt as soon as it is placed. The trench must be excavated wider than the proposed width. Roll and compact the two materials simultaneously. No traffic is permitted on the pavement after rolling until it has cooled to less than 140 F. Roller marks shall not be visible after rolling operations.

.08 Joints. Construct joints as directed and as follows:

628 — ASPHALT PAVEMENT

(a)Stagger longitudinal and transverse joints in successive courses so that one is not

directly above the other.

(b)Stagger transverse joints by the length of the paver.

(c)Stagger longitudinal joints at least 6 in. and arrange so that the longitudinal joint in the

top course is within 6 in. of the line dividing the traffic lanes.

(d)Construct joints in a manner that provides a continuous bond between the old and new

surfaces.

(e)Overlap the existing pavement 1 in. to 1.5 in. when constructing longitudinal joints

adjacent to existing asphalt pavements.

(f)The initial longitudinal roller pass shall be on the uncompacted hot mat and 6 in. to 1 ft

from the joint. The successive roller pass shall compact the overlapped material and the 6 in. to 1 ft material simultaneously.

(g)Apply tack coat to joints as directed. Cut back the edge of the existing pavement for

its full depth at transverse joints when placing a surface course and apply tack coat material as directed.

(h)Apply tack coat to all contact surfaces before placing the mix against curbs, gutters,

headers, manholes, etc.

.09 Edge Drop-off. When paving highways carrying traffic:

(a)Match all compacted pavement courses exceeding 2-1/2 in. in depth with the abutting

lane or shoulder on the same working day.

(b)For compacted pavement courses of 2-1/2 in. or less are placed, use the option of

paving the abutting lane or shoulder on alternate days.

(c)Pave all abutting lanes or shoulders prior to weekends and temporary shutdowns.

(d)Place advance warning traffic control devices as specified in Section 104 where uneven

pavement joints.

.10 Tie-In. When paving highways carrying traffic:

(a)Construct a temporary tie-in at least 4 ft in length for each 1 in. of pavement depth when

the posted speed ≤ 40 mph.

(b)Construct a temporary tie-in at least 10 ft in length for each 1 in. of pavement depth

when the posted speed > 40 mph. 629 — ASPHALT PAVEMENT

(c)Construct temporary tie-ins before traffic is allowed to cross the transverse joint.

(d)Construct temporary tie-ins 10 ft or greater using a paver meeting 504.03.01.

(e)Remove a transverse portion of the existing pavement at the final tie-in point to

maintain the design thickness of the final surface course.

(f)Construct the final tie-in to a length equal to the posted speed per 1 in. depth of the

design thickness of the final course, with a length of at least 25 ft per 1 in. depth and a maximum length of 50 ft per 1 in. depth.

.11 Mix Sampling & Testing. Mix sampling and testing for Quality Control (QC) is the

responsibility of the Producer or Contractor. Identify the QC sampling locations in the Field QC Plan (plant or project site). Perform Quality Assurance (QA) sampling as directed and witnessed by the Administration. Obtain QA samples from behind the paver prior to compaction. The Administration will perform all QA testing.

(a)QC Sampling at the Plant. Refer to MSMT 457. The Engineer will retain all random

sampling documentation. The producer shall sample the mix at the plant. The sample shall be obtained or witnessed by the certified technician. QC plant mix sample results shall not be used in the pay factor calculation. Submit the results to the Administration and identify as Plant samples.

(b)QC Sampling at the Project Site. Refer to MSMT 457. QC and QA samples shall not

be split samples. The certified technician shall sample the mix at the project site. Sampling will be witnessed by the Administration.

(1)A mix lot constitutes all sublots of a mix created during the production of

required tonnage for a lot.

(2)A mix sublot size should not exceed 1000 tons.

(3)A sublot size up to 200 tons can be combined with the previous 1000 ton sublot

placed on the same day.

(4)A new lot number for a mix will be given when there is a change in the approved

job mix formula.

(5)QC project site mix sample results may be used in the pay factor calculation.

(c)QA Sampling at the Project Site. Refer to MSMT 457. Sample mixes at the project

site as specified.

(1)Obtain the samples from behind the paver prior to compaction. Documentation

of random sampling shall be retained by the Engineer. 630 — ASPHALT PAVEMENT

(2)The Contractor’s Certified Technician shall sample the mix at the project site

as witnessed by the Administration.

(3)The Administration will take possession of the QA samples and deliver to the

Laboratory for testing.

(4)A mix sublot size should not exceed 1000 tons. A sublot size up to 200 tons

can be combined with the previous 1000 ton sublot placed on the same day. A mix lot constitutes all sublots of a mix created during the production of required tonnage for a lot. A new lot number for a mix will be given when there is a change in the approved job mix formula.

(d)Mix Acceptance Determination. Obtain at least three behind the paver mix samples

per acceptance lot for mix acceptance determination. An acceptance lot size is approximately equal to 6000 tons of mix per project. A mix acceptance lot ends on the day when 6000 tons is reached.

(1)QC and QA results from behind the paver will be compared based on the F-test

and t-test methods according to MSMT 733 for each pay factor property.

(2)When F-test and t-test method results indicate a QC and QA pay factor property

is not from different populations, QC and QA results will be combined to calculate the mix pay factor property according to MSMT 735 and 504.04.02.

(3)When F-test and t-test method indicate a QC and QA pay factor property is from

different populations, the pay factor property will be determined using QA results only.

(4)The Administration will determine the acceptance evaluation procedure when

less than three QA samples are obtained for an acceptance lot. The results will be made available within five working days.

.12 Sampling & Testing for Density Determination. Refer to MSMT 457. Random core

sampling locations will be selected for each sublot as specified. Sample the QC and QA cores in the presence of the Engineer. Cut 4 in. or 6 in. cores for mixes smaller than 25 mm and 6 in. cores for mixes 25 mm and larger. A density lot is defined as a day’s paving per mix. A sublot shall not exceed 500 tons. A paving day shall begin with a new lot and sublots. The Engineer shall witness the random location coring. At the end of the day’s paving, the Engineer will designate one randomly selected core sublot set for QC and one for QA. The Engineer will note specific reasons for any density waivers and submit the proper forms to the Administration.

(a)Quality Control for Density. The density of the core samples will be expressed as a

percentage of the maximum specific gravity of the mixture for each lot’s placement. 631 — ASPHALT PAVEMENT The maximum specific gravity will be determined in accordance with T 209 and the core’s percent density will be expressed to the nearest 0.1 percent. If more than one mix sample is obtained per day’s placement, an average of all maximum specific gravity tests for the day will be used for the determination of percent density of each core sample. The QC Laboratory will make results of individual days paving available to the Engineer and the Contractor no later than the next working day. Retain core samples until notified of the results of the F & t test.

(b)Quality Assurance for Density. The Engineer will take possession of the core samples

and deliver the cores to the Administration’s Laboratory for testing. The density of the core samples will be expressed as a percentage of the maximum specific gravity of the mixture for each lot’s placement. The maximum specific gravity will be determined in accordance with T 209 and the core’s percent density will be expressed to the nearest 0.1 percent.

(1)If more than one mix sample is obtained per day’s placement, an average of all

maximum specific gravity tests for the day will be used for the determination of percent density of each core sample. The Laboratory will make results of individual days paving available to the Engineer and the asphalt Producer within five working days.

(c)Acceptance. Each asphalt density lot will be evaluated for compliance using the

Engineer’s quality assurance test data and the Contractor’s QC data. The QC and QA core specific gravity data will be analyzed in conformance with MSMT 733 (F-test and t-test method).

(1)If test results are determined to be from the same population, QC and QA sublot

results will be averaged to calculate the density pay factor as specified in

504.04.02

(2)If results are determined not to be from the same population, the pay factor will

be calculated using QA sublot results only. The average QC maximum specific gravity test results and the average project site behind the paver QA maximum specific gravity test results shall be compared.

(3)If QC results and QA results compare within 0.026, the average of the combined

QC and QA results shall be used to calculate each core density. If they do not compare within 0.026, QA maximum specific gravity results shall be used to determine each core density.

(4)Pay reduction or incentive for the pavement compaction lot will be calculated

as specified in 504.04.02. Statistical outliers will be determined according to MSMT 734. 632 — ASPHALT PAVEMENT

(5)An asphalt density lot size shall equal one paving day’s production per mix. A

lot shall be divided into a minimum of five equal sublots. A sublot shall not be greater than 500 tons. When a paving day’s production per mix is greater than 2500 tons, then each sublot size shall be 500 tons or fraction thereof. Acceptance on projects requiring less than 500 tons of asphalt or when asphalt is used in non- traffic areas or on bridge decks will be determined with a thin layer density gauge used according to the manufacturer’s recommendations.

.13 Thin Lifts and Wedge/Level Courses. If an asphalt course is determined to be a thin

lift in accordance with the “Thin Lift Mix Design Identification Table” in 904.04.07, construct a 400 ft to 500 ft control strip on the first day of paving to determine optimum pavement density.

(a)Use a thin-lift nuclear or non-nuclear asphalt density gauge in accordance with the

manufacturer’s recommendations to take readings from the control strip in five random locations to determine roller patterns and the number of passes needed to obtain optimum density. Optimum density is defined as when the average density does not change by more than 1.0 percent between successive roller passes and the percent density is between 90.0 and 97.0.

(b)Core the 5 random gauge reading locations to verify the gauge calibration and to

determine the percent pavement density. The cores will be tested by the contractor’s QC laboratory and results will be verified by the Office of Materials Technology. The QC/QA cores will be saved by the contractor and made available to the Administration for retesting 10 days past after the paving date or as directed.

(c)On the first day of paving, the target optimum density will be determined using the

density gauge readings from the control strip; verified by the core results. The lot average density from the five control strip cores will be used as the target optimum density.

(d)Take a minimum of 10 QC/QA gauge readings daily from random locations per day’s

paving per mix or 2 per 500 tons of paving per mix; whichever yields the higher frequency of locations. A density lot is defined as a day’s paving per mix. A sublot shall not exceed 500 tons. A paving day shall begin with a new lot and sublots.

(e)Any lot average 2.0 percent or more below optimum and below 92 percent shall require

a new control strip to be constructed, tested and approved before paving continues.

(f)Take 2 QA cores daily when production is in excess of 500 tons per location, or when

successive days of less than 500 tons production totals 1000 tons or greater. If the average of the 2 density gauge readings and the average of the two respective QA core densities are within 3.0 lb/ft3, the Administration will accept all the daily density gauge readings. If they do not compare within 3.0 lb/ft3, construct a new control strip and recalibrate the density gauge. 633 — ASPHALT PAVEMENT

(g)Wedge/Level courses placed at variable thicknesses and any area greater than 3/4 in.

shall be tested and accepted in accordance with this Thin Lift specification. Density incentives are not applicable for Thin Lift or Wedge/Level Courses. Apply mix pay factors as determined by the Engineer and the Contractor at the Pre-pave meeting.

.14 Control Strip. When mixes are not determined to be Thin Lifts as specified in

.13, use the option of constructing a control strip for guidance in determining roller patterns

Construct the control strip on the first workday in which asphalt is placed between 400 ft and 500 ft in length. Remove any control strip, if necessary and as determined at no additional cost. The construction of a control strip may be required at any time during placement of asphalt based on the evaluation of compaction results, as determined.

.15 Pavement Surface Checks. Ensure an approved 10 ft straightedge is available at all

times. The surface of each pavement course shall be true to the established line and grade after final compaction of each course. The surface shall also be sufficiently smooth so that the surface does not deviate more than 1/8 in. when the straightedge is placed parallel to the centerline. The transverse slope of the finished surface of each course shall not deviate more than 3/16 in. when the straightedge is placed perpendicular to the centerline. Check transverse joints using the straightedge immediately after the initial rolling. When the surface of each course varies more than 1/8 in. from true, make immediate corrections so the finished joint surface is within tolerance. Areas that are tested and reported as specified in Section 535 – Pavement Surface Profile in the Contract Documents are not applicable to 504.03.15.

.16 Curbs, Gutters, Etc. Construct permanent curbs, gutters, edges, and other supports as

shown and as specified, then backfill prior to placing the asphalt.

.17 Shoulders. Construct shoulders as specified. Shoulders abutting the asphalt surface

course of any two-lane pavement being used by traffic shall be completed as soon as possible after placement of the surface course on that lane.

.18 Pavement Profile. Refer to Section 535 in the Contract Documents

.19 Safety Edge. Construct a sloped edge on the pavement shoulder of open section

roadways using a device attached to the paver that constrains the asphalt head to produce a compacted profile. The device shall adjust to accommodate varying paving thicknesses. The device shall be capable of being detached or raised when not in use. Construct a safety edge when the individual thickness is at least 1.5 in. or greater. The target range of the slope shall not be greater than 45 degrees when measured from the horizontal axis. Construct the sloped edge of multiple lifts on the top two pavement lifts when specified. Construct the entire sloped edge on underlying pavement. 634 — ASPHALT PAVEMENT

(a)Use the safety edge as a standard treatment for the outside edge of all open section

roadways with shoulders up to 6 ft wide.

(b)Do not use the safety edge when the resulting travel lane is less than 11 ft wide.

(c)Using the safety edge magnetic protractor, record 10 angle readings per mile in the

presence of the Engineer. Readings will be witnessed by the Engineer and the results will be documented on Form OOC-91 by the Contractor for the project files. The performance criteria target is for 90 percent of the readings to fall below 45 degrees.

(d)The safety edge does not replace the requirements in Section 609.

MEASUREMENT AND PAYMENT

Asphalt pavement will be measured and paid for at the Contract unit price per ton. The payment will be full compensation for furnishing, hauling, placing all materials including anti-stripping additive, tack coat, control strip, pot hole and spall repairs, setting of lines and grades where specified, and for all material, labor, equipment, tools, and incidentals necessary to complete the work. Temporary Tie-Ins. Placement and removal of the temporary tie-in where asphalt is being applied to the traveled way carrying traffic will not be measured but the cost will be incidental to the pertinent asphalt item. Removal of the existing pavement or structure for the final tie-in will be measured and paid for at the Contract unit price for the pertinent items used. The asphalt for the final tie-in will be measured and paid for at the Contract unit price for the pertinent Asphalt item. Adjustments. Adjustment of existing visible manholes, valve boxes, inlets, or other structures will not be measured but the cost will be incidental to the asphalt item. Adjustment of existing manholes, valve boxes, inlets, or other structures that are encountered below the existing grade will be considered for payment in conformance with GP-4.07. Removal of Existing Raised/Recessed Pavement Markers. Removal of existing raised/recessed pavement markers will not be measured but the cost will be incidental to the asphalt item. Removal of existing raised/recessed pavement markers that are encountered below the existing pavement will be considered for payment in conformance with GP-4.07.

.01 Price Adjustment for Asphalt Binder. A Price Adjustment (PA) will be made to

provide additional compensation to the Contractor or a credit to the Administration for the fluctuation in the cost of asphalt binder. For adjustment purposes, the prevailing base index price will be the price specified for PG 64-22 (PG64S-22) at time of bid opening. Cost differentials between PG 64-22 (PG64S-22) and a binder specified shall be included in the price bid per ton for Asphalt. A historical database will be maintained by the Administration. 635 — ASPHALT PAVEMENT The PA will be made when the index price for the month of placement increases or decreases more than 5 percent of the prevailing base index price. Computations will be as follows: Percent Change = ((Pp – Pb)/ Pb) X 100 PA = T x Q x ((Pp – (D x Pb)) Where: PA= Price Adjustment for the current month T = Design target asphalt content expressed as a decimal Q = Quantity of asphalt placed for the current month Pp = Index price for PG 64-22(PG64S-22) asphalt binder per ton for the month of placement D = 1.05 for increases over 5 percent; 0.95 for decreases over 5 percent Pb = Prevailing base index price for PG 64-22 (PG64S-22) asphalt binder per ton PA resulting in increased payment to the contractor will be paid under the item Price Adjustment for Asphalt Binder. The item amount will be established by the Administration and shall not be revised by the Contractor. PA resulting in a decreased payment will be deducted from monies owed the Contractor.

.02 Payment Adjustments for Asphalt Mix and Pavement Density. Payment

adjustments for pavement density will be based on individual sublot core test data for a given lot and the lot average density as specified in this section and Table 504A. Payment reductions for density and for mix will be made by adjusting the payment for Asphalt. Incentive payments will be made using the Contract items for Asphalt Mix and Pavement Density. The item amounts established by the Administration shall not be revised. Payment reductions for density will be waived for portions of the pavement where a poor foundation is determined as the cause for inadequate density. 636 — ASPHALT PAVEMENT TABLE 504A Dense Graded Asphalt Mixes — Percent of Maximum Density Lot Average % Minimum No Individual Sublot Below %* Pay Factor (DF) 94.0 94.0 1.050 93.8 93.7 1.045 93.6 93.4 1.040 93.4 93.1 1.035 93.2 92.8 1.030 93.0 92.5 1.025 92.8 92.2 1.020 92.6 91.9 1.015 92.4 91.6 1.010 92.2 91.3 1.005 92.0 91.0 1.000 91.8 90.8 0.990 91.6 90.6 0.980 91.4 90.4 0.970 91.2 90.2 0.960 91.0 90.0 0.950 90.8 89.8 0.940 90.6 89.6 0.930 90.4 89.4 0.920 90.2 89.2 0.910 90.0 89.0 0.900 89.8 88.8 0.890 89.6 88.6 0.880 89.4 88.4 0.870 89.2 88.2 0.860 89.0 88.0 0.850 88.8 87.8 0.840 88.6 87.6 0.830 88.4 87.4 0.820 88.2 87.2 0.810 88.0 87.0 0.800 Less than 88.0 87.0 0.750 or rejected by Engineer Note 1: Lots with test data above 97.0 may be rejected. Lots that are accepted will receive a pay adjustment in accordance with the following:

(a)When the density lot average is above 97.5, the pay factor = 75 percent

(b)When 3 sublot densities are above 97.0, the pay factor = 95 percent

(c)When 4 or more sublot densities are above 97.5, the pay factor =

75 percent Note 2: Pay incentive or pay disincentive will not be paid for placements identified as wedge/level courses or thin lift courses. 637 — ASPHALT PAVEMENT Note 3: When the Contractor's core specific gravity data does not compare with the Administration's core specific gravity data, only the Administration's single sublot values and lot average value will be used in acceptance decision. Note 4: The average sublot values and the lot average will be used in acceptance decision. Lots in conformance will be accepted as specified in Section 904 and Section 915, and MSMT 735. A composite pay factor (CPF) for Asphalt content and gradation will be based on the total estimated percent of the lot that is within specification limits using the quality level analysis. Payment adjustments will be computed as follows: Density Lot Payment Adjustment = (DF - 1)x(AP)x(TL) Mix Design Lot Payment Adjustment = (MF - 1)x(AP)x(TL) Where: MF = Mixture pay factor [0.55 + (0.5 x CMPWSL)] Refer to MSMT 735 for CMPWSL. DF = Density pay factor from Table 504A. AP = Adjusted/applicable unit price as specified in 504.04.01. TL = Applicable tonnage per lot.

(a)A lot containing material with a pay factor of less than 1000 may be accepted at the

reduced pay factor if the pay factor is at least 0.800 and there are no isolated defects.

(b)A lot containing material with a pay factor of less than 1000 may be accepted at the

reduced pay factor provided the composite pay factor for asphalt content and grading is at least 0.750, and there are no isolated defects.

(c)An in-place density lot containing nonconforming material that fails to obtain at least a

0.800 pay factor and a mixture lot containing nonconforming material that fails to obtain at least a 0.750 pay factor for asphalt content and gradation will be evaluated to determine acceptance. Lots that are rejected shall be replaced.

(d)Lots with less than five Quality Control or Quality Assurance samples per in-place

density lot will not be evaluated for incentive payment.

(e)When less than three mix samples have been obtained at the time of the acceptance

sampling or at the time a lot is terminated, the Engineer will determine if the material in a shortened lot will be considered a part of the previous lot or whether it will be accepted based on the individual test data. 638 — ASPHALT PAVEMENT

.03 Dispute Resolution. Refer to 915.02.03

All work associated with the construction and angle measurements of the safety edge will not be measured but the cost will be incidental to the pertinent asphalt pavement item. The labor, equipment, and recordation of the angel measurements of the Safety Edge will not be measured for payment and will be incidental to the pertinent asphalt pavement items. All asphalt materials used in the creation of the pavement edge will be included in the measured tonnage related to the pertinent asphalt pavement item and will be eligible for all related adjustments, disincentives, and incentives. Shoulder backup material will be measured and paid for as specified in Section 609. 639

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Source: Standard Specifications for Construction and Materials, 2026 Edition. Pages 638–653 of 1,138. View official source ↗

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