SPECIALNOTEFORFIBER REINFORCEMENTOFASPHALT
PART 1 – GENERAL
1.1DESCRIPTION
ThisSectionincludesspecificationsforfurnishing all materials, equipment, labor, and incidentals for mixingaramidfiber reinforcementsto hot mixasphalt.
1.2DEFINITIONS
A.HMA-hotmixasphalt,withoutaramidfiber.
B.WMA- warm mix asphalt, without aramid fiber.
C.ReinforcedHMA-hotmixasphaltincludingaramidfibersproperlyproportioned,uniformlymixedandcoatedwithasphalt.
D.Aramidfiber-pure aramidfibermeetingthematerialpropertiesofthisspecification,withoutadditivematerials.
E.Deliverymaterial(s)-thematerial(s)combinedwiththepurearamidfibertofacilitateAramidfiberandHMA/WMAproportioning,uniformmixingwiththeHMA/WMA,andasphaltcoatingofthearamidfibers.
F.Aramidproduct-thearamidsupplier’smixtureofpurearamidfiberanddeliverymaterial(s).
G.Manufacturer-thecompanythatproducesthearamidfiberfromrawmaterials.
H.Supplier-thecompanythatoffersanaramidproduct.
PART 2 – PRODUCT
2.1MATERIALS
Meet thefollowingaramidfiber properties.
Property / Measure / StandardMaterial / Aramid / ASTMD276
Form / Monofilamentfibers / Manufacturer Certification
Length / 0.75 inches(+/- 10%) / Manufacturer Cert.
Specific Gravity / 1.44 / ASTMD276
Minimum Tensile Strength / 400,000 psi / ASTMD3379
Maximum Tensile Elongation / 1.8 % / ASTMD3379
DegradationTemperature / 800 degreesF / ASTMD276
AcidandAlkaliResistance / Inert / Manufacturer Cert.
2.2SUBMITTALS
Submit the following.
A.Identifythemixingplant.
B.Provideaspecificationsheetfromthearamidfibermanufacturer.
C.ProvidethefollowingfromthearamidproductsupplieratleastthreeweekspriortoHMA/WMAproduction.
1.Thesupplier’sspecifiedmixrateforthearamidproduct.
2.Certificationthattheamountofaramidfiberinthearamidproductwillbebetween2.1 and 4.0 ounces ofpurearamidfiberforeachtonofhotmixasphalt.
3.Evidenceshowinghowmanytimes,ifany,thesupplier’sfiberproducthasbeensuccessfullyproducedattheasphaltplanttobeusedfortheproject.
4.Provenmethodofintroducingthearamidfibersintothehotmixasphaltwhichwillnotcausethearamidfiberstobecomeairborne.
2.3JOB MIX FORMULA
Whenaramidfiberisrequiredasamixtureingredient,modificationtothejobmixformulaisnotrequired.
PART 3 – EXECUTION
3.1CONSTRUCTION REQUIREMENTS
Storearamidproductinadryenvironmentanddonotallowthemtobeincontactwithmoisture.
Mix3.0ounces (+/- 1.0 ounces)ofaramid fiberspertonofasphalt.The weight applied is for pure aramid fibers only, weight of any delivery materials is not considered.
Haveafibersupplier’srepresentativeonsiteduringthefirstdayofproductionmixing.ThisrequirementcanbewaivediffibersupplierandHMA/WMAproducercansupplyevidenceofsupplier’sbrandoffiberproductbeingsuccessfullyproducedbytheHMA/WMAproducer. The fiber supplier’s representative may be on site for additional days as requested by the Engineer.
Introducethearamidproductasfollows:
1.BatchPlant
Whenabatchtypeplantisused,addthearamidproductdosagetotheaggregateintheweighhopper.Thismaybedonewithloosefibersandafibermeteringdevice,ormaybedonebyusingmanualdosingequipment.Ifnecessary,increasethebatchdrymixingtimetoensurethearamidfibersareuniformlydistributedpriortotheinjectionofasphaltcementintothemixer.
2.DrumPlant
Whenacontinuousordrier-drumtypeplantisused,addthearamidproducttotheRAPmaterialtouniformlydispersewiththeaggregateandinjectedasphalt.Useaseparatearamidproductmeteringdevicefeedsystemtoproportionbyweightoftotalmix,therequiredpercentageoffiberreinforcementintothemixture.Controlthearamidproductmeteringsystemwithaproportioningdevicetomeetthedosingrequirements.
Whenacontinuousordrier-drumtypeplantisusedforlimitedproductionvolumes,theadditionofthearamidproductmaybedonebyusingmanualmeasuringtoolsorequipmentandaddingthemdirectlyontotheRAPbeltorintotheRAPopeningontheplant.Becausethisisnotanautomatedprocess,awrittenprotocolmustbesuppliedbytheproducertodemonstratehowtheywillattainthedosagerequirement,anddocumentationmustbesuppliedbythematerialmanufacturerassuringthismethodwillproducethedesireduniformaramidfiberdistribution.
Mixthearamidfiberwiththeaggregatelonger,ifneeded,toallowthoroughdistributionofaramidfibersattheendofthemixingprocessandtopromoteasphaltcoatingofindividualstrandsofaramidfiber.Atthestartofanyfibermixing,visuallyobservethereinforcedHMA/WMAattheplantandinfirstthreetrucksatthepointofdischargeandpriortodeliverytothejobsite.Observationshallincludeusingashovelorotherdevice.Lookforproperdistributionofaramidfibersandmakemixingadjustmentsifneeded.
WMA:Use of a feeder system will be required for both Drum and Batch plants when producing Warm Mix Asphalt to ensure correct distribution and coating of the aramid fibers. This requirement maybe waved if the asphalt producer can demonstrate complete melting of the delivery material and proper incorporation of the aramid fibers into the WMA.
3.2ACCEPTANCE
Acceptance ofthe reinforcedHMA/WMA willinclude the followingfactors:
1.AramidfiberisproperlyproportionedbasedondocumentationcomparingfiberfeedtoHMA/WMAmixproduction. A log of the total amount of aramid fibers applied certified by fiber manufacturer/supplier shall be required daily.
2.Byvisualinspectionattheendofthemixingprocess,thereisnoclumpingofaramidfiberoraramiddelivery productandthearamidfibersareuniformlydistributed.
3.Allother mixture and densityrequirement ofthe asphaltasdetailed inthe StandardSpecifications,currentedition,shallapply.
PART 4 - MEASUREMENTANDPAYMENT
The Departmentwillmeasure thequantityofFiber Reinforcementfor HMA/WMA as ton ofasphaltplacedwith fibers. Each ton ofasphalt placedwith the aramidfibersaccordingtothis special note will be measuredandpaidforatthe contract unit bid price per ton, andshallinclude fullcompensationfor furnishingalllabor, tools, equipment, and incidentalsfor doing all the work involved in addingthefibers to HMA/WMA.
Code / PayItem / PayUnit24785EC / Fiber ReinforcementforHMA / Tons
SN for Fiber Reinforcement of Asphalt Page 1 of 4