337ASPHALT CONCRETE FRICTION COURSES

337-1Description

Construct an asphalt concrete friction course pavement with the type of mixture specified in the Contract Documents , or when offered as alternates, as selected. This Section specifies mixes designated as FC -5, FC-9.5, and FC -12.5. Obtain Superpave asphalt concrete friction course from a plant that is currently on the Department’s Production Facility Listing. Producers seeking inclusion on the list shall meet the requirements of Section 105. Producers must meet the plant and equipment requirements of modified herein.

337-2Materials

337-2.1General Requirements: Meet the req uirements specified in Division III as

modified herein. The Engineer will base continuing approval of material sources on field performance. Warm mix technologies (additives, foaming techniques, etc.) listed on the Department’s website may be used in the p roduction of the mix. The URL for obtaining this information is: https://www.fdot.gov/materials/laboratory/asphalt/index.shtm .

337-2.2Asphalt Binder: Meet the requirements of Section 916, and any additional

requirements or modifications specified herein for the various mixtures.

337-2.3Coarse Aggregate: Meet the requirements of Section 901, and any additional

requirements or modifications spec ified herein for the various mixtures.

337-2.4Fine Aggregate: Meet the requirements of Section 902, and any additional

requirements or modifications specified herein for the various mixtures.

337-2.5Hydrated Lime: Meet the requirements of AASHTO M 303, Type 1. Provide

certified test results for each shipment of hydrated lime indicating compliance with the specifications.

337-2.6Liquid Anti -Strip Additive: Meet the requirements of 916-4 and be listed on

the Department’s Approved Product List (APL).

337-2.7Fiber Stabilizing Additive (Required for FC -5 only): Use either a mineral or

cellulose fiber stabilizing additive. Meet the following requirements: 337-2.7.1 Mineral Fibers: Use mineral fibers (made from virgin basalt, diabase, or slag) treated with a cationic sizing agent to enhance the disbursement of the fiber, as well as to increase adhesion of the fiber surface to the bitumen. Meet the following requirements for physical properties:

Average fiber length: 0.25 inch (maximum) Average fiber thickness: 0.0002 inch (maximum)

Percent passing No. 60 Sieve: 90 - 100 Percent passing No. 230 Sieve: 65 - 100 Provide certified test results for each batch of fiber material indicating compliance with the above tests. 337-2.7.2 Cellulose Fibers: Use cellulose fibers meeting the following requirements: 314 FY 2023-24 Return to Table of Contents

Percent passing No. 100 sieve: 60 -80

Percent passing No. 20 sieve: 80 -95 Percent passing No. 40 sieve: 45 -85 Percent passing No. 100 sieve: 5 -40

Provide certified test results for each batch of fiber material indicating compliance wi th the above tests.

337-3General Composition of Mixes

337-3.1General: Use a bituminous mixture composed of aggregate (coarse, fine, or a

mixture thereof), asphalt binder , and in some cases, fibers and/or hydrated lime. Size, uniformly grade and combine the aggregate fractions in such proportions that the resulting mix meets the requirements of this Section.

337-3.2Specific Component Requirements by Mix:

337-3.2.1 FC-5: 337-3.2.1.1 Aggregates: Use an aggregate blend which consists of either 100% crushed granite and/or granitic gneiss or 100% crushed limestone and/or crushed shell rock. Do not blend granite and/or granitic gneiss with limestone and/or shell rock for FC -5 mixtures. A list of aggregates approved for use in friction co urse may be available on the Department’s website. The URL for obtaining this information, if available, is: https://mac.fdot.gov/ . 337-3.2.1.2 Asphalt Binder: Use an asphalt binder as called for in t he Contract Documents meeting the requirements of Section 916. High polymer binder may be substituted in a mixture with PG 76-22 binder at no additional cost to the Department. 337-3.2.1.3 Hydrated Lime: Add the lime at a dosage rate of 1.0% by weight of the total dry aggregate to mixes containing granite or granitic gneiss from Georgia or Alabama. Add the lime at a dosage of 1.5% by weight of the total dry aggregate to mixes containing any amount of gran ite from Nova Scotia . 337-3.2.1.4 Liquid Anti -Strip Additive: Use a liquid anti -strip additive at the approved dosage rate as indicated on the APL for all mixtures . 337-3.2.1.5 Fiber Stabilizing Additive: Add either mineral fibers at a dosage rate of 0.4% by weight of the total mix, or cellulose fibers at a dosage rate of 0.3% by weight of total mix. 337-3.2.2 FC-9.5 and FC -12.5: 337-3.2.2.1: Aggregates: Use an aggregate blend of approved friction course aggregates that consists of crushed granit e, crushed granitic gneiss, crushed limestone, crushed shell rock, or a combination of the above. As an exception, mixes that contain a minimum of 60% of approved friction course aggregates of crushed granite and/or crushed granitic gneiss may either conta in: up to 40% fine aggregate from other sources of aggregate not 315 FY 2023-24 Return to Table of Contents approved for friction courses or a combination of up to 20% RAP and the remaining fine aggregate from other sources of aggregate not approved for friction courses. Mixtures utilizing High Polymer (HP) binder are not allowed to contain RAP. A list of aggregates approved for use in friction course may be available on the Department’s website. The URL for obtaining this information, if available, is: https://mac.fdot.gov/ . 337-3.2.2.2: Asphalt Binder: Use an asphalt binder as called for in t he Contract Documents meeting the requirements of Section 916. High polymer binder may be substituted in a mixture with PG 76-22 binder at no additional cost to the Department.

337-3.3Grading Requirements:

337-3.3.1 FC-5: Use a mixture having a gradation at design within the ranges shown in Table 337-1.

Table 337-1 FC-5 Gradation Design Ran ge 3/4 inch 1/2 inch 3/8 inch No. 4 No. 8 No. 16 No. 30 No. 50 No. 100 No. 200 100 85-100 60-75 15-25 5-10 -- -- -- -- 2-5

337-3.3.2 FC-9.5: Meet the design gradation requirements for a SP -9.5 Superpave fine mix as defined in 334 -3.2.2. 337-3.3.3 FC-12.5: Meet the design gradation requirements for a SP -12.5 Superpave fine mix as defined in 334 -3.2.2.

337-4Mix Design

337-4.1FC-5: The Department will design the FC -5 mixtures. Furnish the materials and

all appropriate information (source, gradation, etc.) as specified in 334 -3.2.7. The Department will have t hree weeks to design the mix. The Department will establish the design binder content for FC -5 within the following ranges based on aggregate type:

Table 337 -2 FC-5 Percent Binder Content Aggregate Type Percent Binder Content Crushed Granite and/or Granitic Gneiss 6.0 - 7.5 Crushed Limestone and/or Shell Rock 6.5 - 8.0

337-4.2FC-9.5 and FC -12.5: Provide a mix design conforming to the requirements of

334-3.2unless otherwise designated in the plans. Where the plans call for an FC -12.5, an FC -9.5

may be substituted for the FC -12.5 at no additional cost provided the thickness requirements of 334-1.4.1 are met.

337-4.3Revision of Mix Design: For FC-5, FC-9.5 and FC -12.5, meet the requirements

of 334-3.3. For FC -5, all revisions must fall within the gradation limits defined in Table 337-1.

337-5Contractor’s Process Control

Provide the necessary pr ocess control of the friction course mix and construction in accordance with the applicable provisions of 320-2, 330-2 and 334 -4. 316 FY 2023-24 Return to Table of Contents The Engineer will monitor the spread rate periodically to ensure uniform thickness. Perform quality control procedures for da ily monitoring and control of spread rate variability. If the spread rate varies by more than 5% of the spread rate set by the Engineer in accordance with 337-8, immediately make all corrections necessary to bring the spread rate into the acceptable range.

337-6Acceptance of the Mixture

337-6.1FC-9.5 and FC -12.5: Meet the requirements of 334 -5

337-6.2FC-5: Meet the requirements of 334 -5 with the following exceptions:

asphalt binder content (P b) only.

prior to testing) will not be required as part of 334 -5.1.1.

into four equal sublots of 500 tons each.

modified to include (P -3/8, P-4, and P -8) with a maximum difference per FM 1-T 030 (Figure 2).

in accordance with 334 -5.8. No density testing will be required for these mixtures.

Table 337-3 FC-5 Master Production Range Characteristic Tolerance (1) Asphalt Binder Content (%) Target ± 0.60 Passing 3/8 inch Sieve (%) Target ± 7.50 Passing No. 4 Sieve (%) Target ± 6.00 Passing No. 8 Sieve (%) Target ± 3.50

337-6.2.1 Individual Test Tolerances for FC -5 Production: Terminate the LOT if any of the following Quality Control (QC) failures occur:

meet the requirements of Table 337-3,

of the following sieve sizes (P -3/8, P-4, and P -8) do not meet the requirements of Table 337-3. The two consecutive failures must be on the same sieve. When a LOT is terminated d ue to a QC failure, stop production of the mixture until the problem is resolved to the satisfaction of the QC Managers and/or Asphalt Plant Level II Technicians responsible for the decision to resume production after a QC failure, as identified in Section 105. In the event that it can be demonstrated that the problem can immediately be or already has been resolved, it will not be necessary to stop production. When a LOT is terminated, make all necessary changes to correct the problem. Do not resume production until appropriate corrections have been made. Inform the Engineer of the problem and corrections made to correct the problem. After resuming production, sample and test the material 317 FY 2023-24 Return to Table of Contents to verify that the changes have corrected the problem. Summarize this information and provide it to the Engineer prior to the end of the work shift when production resumes. In the event that a QC failure is not addressed as defined above, the Engineer’s approval will be required prior to resuming production after any futu re QC failures. Address any material represented by a failing test result in accordance with 334-5.9.5. Any LOT terminated under this Subarticle will be limited to a maximum Pay Factor of 1.00 (as defi ned in 337 -12.3) for each quality characteristic.

337-7Special Construction Requirements

337-7.1Hot Storage of FC-5 Mixtures: When using surge or storage bins in the normal

production of FC-5, do not leave mixtures containing mineral fibers in the surge or storage bin

for more than one hour. Do not leave mixtures containing cellulose fibers in the surge or storage

bin for more than 1-1/2 hours.

337-7.2Longitudinal Grade Controls for Open-Graded Friction Courses: On FC-5,

use either longitudinal grade control (skid, ski or traveling stringline) or a joint matcher.

337-7.3Temperature Requirements for FC-5:

337-7.3.1 Air Temperature at Laydown: Meet the requirements of Table 330-1.

337-7.3.2 Temperature of the Mix: Heat and combine the asphalt binder and

aggregate in a manner to produce a mix having a temperature, when discharged from the plant,

meeting the requirements of 320-6.3. Meet all requirements of 330-6.1.3 at the roadway. The

target mixing temperature shall be established by the Contractor. The target mixing temperature

may be reduced when using warm mix technology.

337-7.4Compaction of FC-5: Provide two, static steel-wheeled rollers, with an effective

compactive weight in the range of 135 to 200 pounds per linear inch (PLI), determined as

follows:

(Any variation of this equipment requirement must be approved by the Engineer.) Establish an

appropriate rolling pattern for the pavement in order to effectively seat the mixture without

crushing the aggregate. In the event that the roller begins to crush the aggregate, reduce the

number of coverages or the PLI of the rollers. If the rollers continue to crush the aggregate, use a

tandem steel-wheel roller weighing not more than 135 PLI of drum width.

337-7.5Temperature Requirements for FC-9.5 and FC-12.5:

337-7.5.1 Air Temperature at Laydown: Meet the requirements of Table 330-1.

337-7.5.2 Temperature of the Mix: Heat and combine the asphalt binder and

aggregate in a manner to produce a mix having a temperature, when discharged from the plant,

meeting the requirements of 320-6.3. Meet all requirements of 330-6.1.3 at the roadway.

337-7.6Prevention of Adhesion: To minimize adhesion to the drum during the rolling

operations, the Contractor may add a small amount of liquid detergent to the water in the roller.

At intersections and in other areas where the pavement may be subjected to cross-

traffic before it has cooled, spray the approaches with water to wet the tires of the approaching

vehicles before they cross the pavement.

337-7.7Transportation Requirements of Friction Course Mixtures: Cover all loads

of friction course mixtures with a tarpaulin, or waterproof cover, meeting requirements of 320-7. (inches)DrumsofWidthTotal

(pounds)RollerofWeightTotal

PLI = 318FY 2023-24Return to Table of Contents

337-8Thickness of Friction Courses

337-8.1FC-9.5 and FC-12.5: The thickness of the friction course layer will be the plan

thickness as shown in the Contract Documents. For construction purposes, the plan thickness

will be converted to spread rate as defined in 334-1.4.

Plan quantities are based on a Gmm of 2.540, corresponding to a spread rate of

110 lb/yd -in. Pay quantities will be based on the actual maximum specific gravity of the mix

being used.

337-8.2FC-5: The total thickness of the FC-5 layer will be the plan thickness as shown

in the Contract Documents. For construction purposes, the plan thickness will be converted to

spread rate based on the combined aggregate bulk specific gravity of the asphalt mix being used

as shown in the following equation:

Spread rate (lb/yd ) = t x Gsb x 40.5

Where: t = Thickness (in.) (Plan thickness)

Gsb = Combined aggregate bulk specific gravity from the verified

mix design

The weight of the mixture shall be determined as provided in 320-3.2.

Plan quantities are based on a Gsb of 2.635, corresponding to a spread rate of

80 pounds per square yard for a 3/4 inch layer. Pay quantities will be based on the actual

combined aggregate bulk specific gravity (Gsb) of the mix being used.

337-9Special Equipment Requirements for FC-5

337-9.1Fiber Supply System: Use a separate feed system to accurately proportion the

required quantity of fibers into the mixture in such a manner that uniform distribution is

obtained. Interlock the proportioning device with the aggregate feed or weigh system to maintain

the correct proportions for all rates of production and batch sizes. Control the proportion of fibers

to within plus or minus 10% of the amount of fibers required. Provide flow indicators or sensing

devices for the fiber system, interlocked with plant controls so that an alarm will be activated if

introduction of the fiber fails. Stop production of the asphalt mixture and resume production

once the fiber supply system is operating correctly.

When a batch plant is used, add the fiber to the aggregate in the weigh hopper or

as approved and directed by the Engineer. Increase the batch dry mixing time by 8 to 12 seconds,

or as directed by the Engineer, from the time the aggregate is completely emptied into the

pugmill. Ensure that the fibers are uniformly distributed prior to the addition of asphalt binder

into the pugmill.

When a drum-mix plant is used, add and uniformly disperse the fiber with the

aggregate prior to the addition of the asphalt binder. Add the fiber in such a manner that it will

not become entrained in the exhaust system of the drier or plant.

337-9.2Hydrated Lime Supply System: For FC-5 mixes containing granite, use a

separate feed system to accurately proportion the required quantity of hydrated lime into the

mixture in such a manner that uniform coating of the aggregate is obtained prior to the addition

of the asphalt binder. Add the hydrated lime in such a manner that it will not become entrained in

the exhaust system of the drier or plant. Interlock the proportioning device with the aggregate

feed or weigh system to maintain the correct proportions for all rates of production and batch

sizes and to ensure that all mixture produced is properly treated with hydrated lime. Control the

proportion of hydrated lime to within plus or minus 10% of the amount of hydrated lime 319FY 2023-24Return to Table of Contents

required. Provide flow indicators or sensing devices for the hydrated lime system, interlocked

with plant controls so that an alarm will be activated if introduction of the hydrated lime fails.

Stop production of the asphalt mixture and resume production once the hydrated lime supply

system is operating correctly. The addition of the hydrated lime to the aggregate may be

accomplished by Method A or B as follows:

337-9.2.1 Method A - Dry Form: Add hydrated lime in a dry form to the mixture

according to the type of asphalt plant being used.

When a batch plant is used, add the hydrated lime to the aggregate in the

weigh hopper or as approved and directed by the Engineer. Increase the batch dry mixing time

by eight to twelve seconds, or as directed by the Engineer, from the time the aggregate is

completely emptied into the pugmill. Uniformly distribute the hydrated lime prior to the addition

of asphalt binder into the pugmill.

When a drum-mix plant is used, add and uniformly disperse the hydrated

lime to the aggregate prior to the addition of the asphalt binder. Add the hydrated lime in such a

manner that it will not become entrained in the exhaust system of the drier or plant.

337-9.2.2 Method B - Hydrated Lime/Water Slurry: Add the required quantity

of hydrated lime (based on dry weight) in a hydrated lime/water slurry form to the aggregate.

Provide a solution consisting of hydrated lime and water in concentrations as directed by the

Engineer. Use a plant equipped to blend and maintain the hydrated lime in suspension and to mix

it with the aggregates uniformly in the proportions specified.

337-9.3Hydrated Lime Pretreatment: For FC-5 mixes containing granite, as an

alternative to 337-9.2, pretreat the aggregate with hydrated lime prior to incorporating the

aggregate into the mixture. Use a feed system to accurately proportion the aggregate and

required quantity of hydrated lime, and mix them in such a manner that uniform coating of the

aggregate is obtained. Control the proportion of hydrated lime to within plus or minus 10% of

the amount required. Aggregate pretreated with hydrated lime in this manner shall be

incorporated into the asphalt mixture within 45 days of pretreatment.

337-9.3.1 Hydrated Lime Pretreatment Methods: Pretreat the aggregate using

one of the following two methods:

Pretreatment Method A - Dry Form: Add the required quantity of hydrated

lime in a dry form to the aggregate. Assure that the aggregate at the time of pretreatment contains

a minimum of 3% moisture over saturated surface dry (SSD) conditions. Utilize equipment to

accurately proportion the aggregate and hydrated lime and mix them in such a manner as to

provide a uniform coating.

Pretreatment Method B - Hydrated Lime/Water Slurry: Add the required

quantity of hydrated lime (based on dry weight) in a hydrated lime/water slurry form to the

aggregate. Provide a solution consisting of hydrated lime and water in a concentration to provide

effective treatment. Use equipment to blend and maintain the hydrated lime in suspension, to

accurately proportion the aggregate and hydrated lime/water slurry, and to mix them to provide a

uniform coating.

337-9.3.2 Blending QC Records: Maintain adequate QC records for the

Engineer’s review for all pretreatment activities. Include as a minimum the following

information (for each batch or day’s run of pretreatment): pretreatment date, aggregate

certification information, certified test results for the hydrated lime, aggregate moisture content

prior to blending, as-blended quantities of aggregate and hydrated lime, project number,

customer name, and shipping date. 320FY 2023-24Return to Table of Contents

337-9.3.3 Certification: In addition to the aggregate certification, provide a

certification with each load of material delivered to the hot mix asphalt plant, that the material

has been pretreated in conformance with these specifications. Include also the date the material

was pretreated.

337-10Failing Material

Meet the requirements of 334-5.9. For FC-5, use the Master Production Range defined in

Table 337-3 in lieu of Table 334-6.

337-11Method of Measurement

For the work specified under this Section (including the pertinent provisions of

Sections 320 and 330), the quantity to be paid for will be the weight of the mixture, in tons. For

each pay item, the pay quantity will be based on the quantity placed on the project, limited to

110% of the adjusted plan quantity for the pay item. For dense-graded mixes, the adjusted plan

quantity will be determined by dividing the pay item’s original plan quantity (including any

Engineer approved quantity revisions) by the design Gmm stated in 334-1.4, then multiplying it

by the tonnage-weighted average Gmm of the mixes used for the pay item. For open graded

mixes, the adjusted plan quantity will be determined by dividing the pay item’s original plan

quantity (including any Engineer approved quantity revisions) by the design Gsb stated in

337-8.2, then multiplying it by the tonnage-weighted average Gsb of the mixes used for the pay

item.

The bid price for the asphalt mix will include the cost of the asphalt binder (asphalt

rubber (or polymer), asphalt cement, ground tire rubber, anti-stripping additive, blending and

handling) and the tack coat application as directed in 300-8, as well as fiber stabilizing additive

and hydrated lime (if required). There will be no separate payment or unit price adjustment for

the asphalt binder material in the asphalt mix. The weight will be determined as provided in

320-3.2(including the provisions for the automatic recordation system).

Prepare and submit a Certification of Quantities to the Engineer in accordance with

9-2.1.2.

337-12Basis of Payment

337-12.1General: Price and payment will be full compensation for all the work

specified under this Section (including the applicable requirements of Sections 320 and 330).

Based upon the quality of the material, a pay adjustment will be applied to the bid

price of the material as determined on a LOT by LOT basis. The pay adjustment will be assessed

by calculating a Pay Factor for individual quality characteristics. The pay adjustment will be

computed by multiplying a Composite Pay Factor for the LOT by the bid price per ton.

337-12.2FC-9.5 and FC-12.5: Meet the requirements of 334-8

337-12.3FC-5: Meet the requirements of 334-8 with the following exceptions:

passing the 3/8 inch, the No. 4, and the No. 8 sieves only.

CPF = [(0.20 x PF 3/8 inch) + (0.30 x PF No. 4) + (0.10 x PF No. 8) +

(0.40 x PF AC)] 321FY 2023-24Return to Table of Contents

Table 337-4

Small Quantity Pay Table for FC-5

Pay Factor 1-Test Deviation 2-Test Average Deviation

Asphalt Binder Content (%)

1.05 0.00-0.25 0.00-0.18

1.00 0.26-0.50 0.19-0.35

0.90 0.51-0.60 0.36-0.42

0.80 >0.60 >0.42

3/8 inch Sieve (%)

1.05 0.00-3.25 0.00-2.30

1.00 3.26-6.50 2.31-4.60

0.90 6.51-7.50 4.61-5.30

0.80 >7.50 >5.30

No. 4 Sieve (%)

1.05 0.00-2.50 0.00-1.77

1.00 2.51-5.00 1.78-3.54

0.90 5.01-6.00 3.55-4.24

0.80 >6.00 >4.24

No. 8 Sieve (%)

1.05 0.00-1.50 0.00-1.06

1.00 1.51-3.00 1.07-2.12

0.90 3.01-3.50 2.13-2.47

0.80 >3.50 >2.47

Table 337-5

Specification Limits for FC-5

Quality Characteristic Specification Limits

Asphalt Binder Content (%) Target ± 0.45

Passing 3/8 inch sieve (%) Target ± 6.00

Passing No. 4 sieve (%) Target ± 4.50

Passing No. 8 sieve (%) Target ± 2.50

337-12.4Payment: Payment will be made under:

Item No. 337- 7- Asphaltic Concrete Friction Course - per ton. 322FY 2023-24Return to Table of Contents VALUE ADDED ASPHALT PAVEMENT

338-1Description

Construct value added asphalt pavement consisting of asphalt concrete structural course and asphalt concrete friction course, subject to a three year warranty period after final acceptance of the Contract in accordance with 5 -11. For purposes of this Specification, the Responsible Party, as designated herein, is responsible for performance of the value added asphalt pavement including continued responsibility for performing all remedial work associated with pavement distresses exceeding threshold values determined in accordance with this Section, and as to which notice was provided to the Responsible Party. The work specified in this Section will not be paid for directly, b ut will be considered as incidental to other Contract items.

338-2Materials and Construction Requirements

Meet the following requirements: Hot Bituminous Mixtures - Plant, Methods and Equipment ................................ ........................... Section 320 Hot Bituminous Mixtures - General Construction Requirements ................................ ...................... Section 330 Superpave Asphalt Concrete ............................... Section 334 Asphalt Concrete Friction Courses ....................... Section 337

338-3Responsible Party

Prior to any value added asphalt pavement being placed on the project, the Contractor shall designate a Responsible Party to accept responsibility for maintaining the value added asphalt pavement, when remedial work is required. When the scope of the asphalt work is only milling and resurfacing, a nd there is no construction of the embankment, subgrade or base below the pavement included in the Contract, the Responsible Party may be either the Contractor or the Department approved subcontractor performing the value added asphalt pavement work. When the construction of the embankment, subgrade or base below the pavement is included in the Contract, in addition to the construction of the asphalt concrete structural course and asphalt concrete friction course, the Contractor shall be considered as the Responsible Party. When the Responsible Party is a subcontractor, the subcontractor must be pre -qualified with the Department in the category of asphalt, and such designation must be made to the Department by the Contractor. The proposed subcontractor must execute and submit to the Department a form, provided by the Department, prior to or concurrent with the Contractor’s request to sublet any value added asphalt pavement work, stipulating that the subcontractor assumes all responsibility as the Responsible Party for the value added asphalt pavement within the three-year warranty period. Failure to timely designate the Responsible Party will result in the Contractor being the Responsible Party unless otherwise agreed to in writing by the Department. Upon final acceptance of the Contract in accordance with 5 -11, the Contractor’s responsibility for maintenance of all the work or facilities within the project limits of the Contract will terminate in accordance with 5 -11; with the sole excepti on that the obligations set 323 FY 2023-24 Return to Table of Contents