道路工程材料教学课件Road Engineering Materials ch5

RoadEngineeringMaterials

道路工程材料CollegeofAutomobileandTrafficEngineering汽车与交通学院QingdaoTechnologicalUniversity青岛理工大学Ch5BituminousMaterials5.1Typesofasphalt5.2Petroleumasphalt5.3Propertiesofasphalt5.4Asphaltgrades5.5Sprayapplications5.6Testing5.1TypesofasphaltBitumenisasolid，semisolid，orviscouscementitiousmaterial，naturalormanufactured，andcomposedprincipallyofvariousmixturesofcomplexhydrocarbons(烃,碳氢化合物).FeaturesofbitumenCompletelysolubleincarbondisulfide(CS2)NonvolatileNontoxicSoftenwhenheated沥青分类沥青材料分为地沥青和焦油沥青两大类。地沥青又分为天然沥青和石油沥青天然沥青是石油渗出地表经长期暴露和蒸发后的残留物；石油沥青是将精制加工石油所残余的渣油，经适当的工艺处理后得到的产品。焦油沥青是煤、木材等有机物干馏加工所得的焦油经再加工后的产品。工程中采用的沥青绝大多数是石油沥青，石油沥青是复杂的碳氢化合物与其非金属衍生物组成的混合物。通常沥青闪点在240℃~330℃之间，燃点比闪点约高3℃~6℃度，因此施工温度应控制在闪点以下。地沥青石油沥青沥青膏焦油沥青焦油天然沥青天然沥青岩石沥青乳化沥青稀释(石油)沥青氧化沥青慢凝中凝快凝沥青（烃,碳氢化合物）UsesofbituminousmaterialsBitumenspossessanumberofpropertiesthatmakethemusefulintheconstructionabilitytoadheretosolidparticlesimpermeabilityorwaterresistanceUsesofbituminousmaterialsroadwayspavementsmanyconstructionproductssuchasroofingfelt,caulkingcompound,waterproofingcompounds,wallboard,buildingpaper,paints,etc.waterproofcoatingsforwallsandbelow-gradestructures．5.1.1TarsandpitchesTars,alongwithpitches,aretheproductsofdistillationofmaterialssuchaswood,coal,andshale.Whenthesematerialsundergodestructivedistillation,theresultingcondensate冷凝物

istar．Furtherprocessingyieldsasolidorsemisolidresidueknownaspitch．Tar焦油Generallyby-productofcoke(fromcoal)productionWhencoalisheatedincokeovens,itisreducedtocoke.Thegases(vaporizedoils)generatedduringtheprocessarecollectedfromtheovenandrefined.Thedistillationoflighteroilsproducestar.焦油是煤炭在焦化过程中产生的。其产量约占装炉煤的3%~4%，在常温常压下其产品呈黑色粘稠液状，密度通常在0.95-1.10g/cm3之间，焦油又称煤焦油。Tarpitches焦油沥青Tarpitchesareusedforbuilt-uproofingandwaterproofingofundergroundandabovegroundconstructionsuchasfoundations，retainingwalls，dams，andbridges．Abovegroundstructuresexperiencegreatfluctuationsinenvironmentalconditions，andwaterproofingcompoundsshouldbeabletowithstandthesechangeswithoutbecomingbrittleortoosoft．5.1.2AsphaltsAsphaltsarecementitiousmaterialsinwhichthepredominantconstituentmaterialsarebitumens.NaturaldepositsorpetroleumasphaltTheconsistencyofasphaltsvarieswidelyfromsolidtosemisolidatnormaltemperatureThenaturaldepositsofasphaltsareoftwotypes：NaturalrockasphaltsDepositsofsandstoneorlimestonefilledwithasphaltsNativeasphaltsorlakeasphaltsLakeTrinidad特立尼达岛，WestIndies(a110-acrelakecontainingabout40percentbitumenmixedwithwater,finesiliceoussilt,clay,andorganicmatter);Bermudez，Venezuela(lakeasphaltcontainingabout65percentbitumen)TrinidadLakeAsphalt特立尼达岛

特立尼达和多巴哥的主岛。与委内瑞拉东北部海岸相望，最近处仅11公里。面积4，828平方公里。人口101.6万（1980）。1532年起沦为西班牙殖民地，后被英、荷、法侵占，1802年成为英国殖民地。1962年独立后成为该国领土的主要部分。岛上北部、中部、南部有三条大致东西向的低山脉，最高峰为北部山脉的阿里波山（940米）。向南地势降低，大部分地方为不超过150米的低平原。沿海多沼泽。热带气候，炎热潮湿，有干季。河流短促、经济以石油工业为主。南部石油带（面积约2，000平方公里）及沿海大陆架富藏石油和天然气，西南部有闻名世界的沥青湖。炼油能力超过开采能力，主要炼油中心和石油输出港是皮埃尔角、福廷角和拉布雷阿，均在西南部帕里亚湾岸。农作区主要分布在中部平原，甘蔗为传统经济作物。

5.2PetroleumasphaltPetroleumasphaltsareclassifiedintofourtypes：AsphaltcementsCutbackasphaltsEmulsifiedasphaltsAir-blownasphaltsUsagesofpetroleumasphaltsPetroleumasphaltsareusedinconstructionofflexiblepavementsroofconstruction(asphaltshingles,rolledroofing,andbuilt-uproofing),forinsulation(electricalinsulationandbuildingpaper)waterproofing(sprays,paints,andbituminousfabrics)canalliningsealsubgradesagainstthemigrationofwaterJointseals5.2PetroleumasphaltPetroleumasphaltsareclassifiedintofourtypes：AsphaltcementsCutbackasphaltsEmulsifiedasphaltsAir-blownasphalts5.2.1AsphaltCementAsphaltcementisverystickyandhighlyviscous,especiallypreparedwiththequalityandconsistencyrequiredinthemanufactureofasphaltpavements(hot-mixpavements).Itisobtainedafterseparationoflubricatingoilsfromcrudepetroleum.

PropertiesofasphaltcementItpossessesexcellentbindingpropertiesandadheresverywelltoaggregateparticles.whenusedinpavementconstructionitisnecessarytoheatboththeasphaltcementandtheaggregatespriortomixing．superiorwaterproofqualitiesPavementbuiltusingpavingasphaltiswaterproofandresistanttomanytypesofchemicalattack.5.2PetroleumasphaltPetroleumasphaltsareclassifiedintofourtypes：AsphaltcementsCutbackasphaltsEmulsifiedasphaltsAir-blownasphalts5.2.2CutbackAsphaltsTwotypesofasphaltareavailableinliquidform:cutbackasphaltemulsifiedasphaltCutbackasphalt----isasphaltcementthatisliquefiedbyblendingwithpetroleumsolvents(calleddiluents).CutbackasphaltaredividedintothreetypesSlow-curingMedium-curingRapid-curingSlow-curingcutbackasphaltSlow-curingcutbackasphaltisasphaltcementblendedwithoilsoflowvolatility，suchasdieseloil柴油.Itsviscosityvalueislowandithardensveryslowly.Itisusedforcoldlaidpavementbases.Medium-curingcutbackasphaltMedium-curingcutbackasphaltisobtainedbyblendingasphaltcementwithkerosene-煤油typediluentsofmediumvolatility.Ithardensfasterthantheslow-curingandslowerthantherapid-curingtype.Usedforcold-laidpavementbases(plantmixedandmixedinplace)andsurfacetreatmentsRapid-curingcutbackasphaltRapid-curingcutbackasphaltisasphaltcementblendedwithnaphthaorgasoline-汽油typediluentsofhighvolatility.Thediluentsinrapid-curingasphaltevaporatequickly.Usedprimarilyinmixed-in-placepavementmixesandsurfacetreatments.5.2PetroleumasphaltPetroleumasphaltsareclassifiedintofourtypes：AsphaltcementsCutbackasphaltsEmulsifiedasphaltsAir-blownasphalts5.2.3EmulsifiedAsphaltEmulsifiedasphaltiscomposedofasphaltcementandwaterthatcontainsasmallamountofanemulsifyingagent．Soapswater-solublechemicalsfineclay乳化沥青乳化沥青是将通常高温使用的道路沥青，经过机械搅拌和化学稳定的方法（乳化），扩散到水中而液化成常温下粘度很低、流动性很好的一种道路建筑材料。可以常温使用，且可以和冷的和潮湿的石料一起使用。当乳化沥青破乳凝固时--还原为连续的沥青并且水分完全排除掉，道路材料的最终强度才能形成。、在众多的道路建设应用中，乳化沥青提供了一种比热沥青更为安全、节能和环保的系统，因为这种工艺避免了高温操作、加热和有害排放。乳化沥青主要用于道路的升级与养护，如石屑封层，还有多种独特的、其它沥青材料不可替代的应用，如冷拌料、稀浆封层。乳化沥青亦可用于新建道路施工，如粘层油、透层油等。

advantagesofemulsifiedasphaltemulsifiedasphaltcanbeappliedduringdampweatherandwithaggregatesthatarecoldorhot．thequantityofmaterialsappliediscontrolledautomaticallybecauseanyexcess(water)willdrainintothesubgrade．savingenergyTheuseofemulsifiedasphaltalsoeliminatestheuseoffuelrequiredtoheatanddrytheaggregatesintheasphaltcementmixturesreducesenergyrequirementsthroughreductionoreliminationofpetroleumdistillatesusedincutbackasphalts.disadvantageofemulsifiedasphaltpollutionbecausetheasphaltissuspendedinwater,itissusceptibletobeingwashedoffaroadsurfacebyrainwaterifnotsufficientlycured.Theunbrokenemulsionsmaybecarriedintostreams,causinggroundcontamination.5.2PetroleumasphaltPetroleumasphaltsareclassifiedintofourtypes：AsphaltcementsCutbackasphaltsEmulsifiedasphaltsAir-blownasphalts5.2.4BlownAsphaltBlownasphaltisobtainedbyblowingairthroughthesemisolidresidueobtainedduringthelaterstagesofthedistillationprocess．PropertiesrelativelyfirminconsistencyDuctileweatherresistantandcanwithstandtemperaturechangesverywell．UsagesofBlownasphaltsBlownasphaltsuseinthemanufactureroofingmaterialswaterproofpaintsjointfillers(forconcretepavements)undersealingold，rigidpavementsmineralrubber5.3PropertiesofAsphaltandTestingPropertiesofasphaltorasphalticmaterialare：Adhesion粘附性Consistency稠度Specificgravity比重Durability耐久性Rateofcuring凝结速率Ductility延度Agingandhardening老化及硬化Resistancetoreactionwithwater水敏感性Temperaturesusceptibility感温性PropertiesofAsphalt5.3.1Consistency5.3.2Specificgravity5.3.3Durability5.3.4Ductility5.3.5Temperaturesusceptibility5.3.1ConsistencyConsistencymeasuresthedegreeoffluidityorplasticityofasphaltcementatanyparticulartemperature．IndexViscosity粘度Penetration针入度ViscosityAttemperaturesbetween70-150°C，asphaltbehavesasaviscousliquid．Below70°C，thebehaviorcanbedescribedaslinearlyviscoelastic.Belowabout-20°C，asphaltbecomesaweakandbrittleelasticsolid.ViscosityofasphaltViscosityViscosityisameasureoftheresistancetoflowandisthefundamentalconsistencymeasurementinabsoluteunits．TypesofViscosityAbsoluteviscosityKinematicviscosityEquationofViscosityItisexpressedastheratioofshearstresstoshearrate.Attemperaturesabove150°C，theratioisconstant;Whenthetemperaturedecreases,theratioofshearstresstoshearratefluctuates.shearstressshearrateViscosity绝对黏度：当沥青层间的速度变化梯度（即剪变率）为一个单位时，每单位体积上受到的内摩阻力。取一对相互平行的平面，在平面之间分布有一层沥青薄膜，薄膜与平面的吸附力远大于薄膜内部胶团之间的作用力。当下层平面固定时，外力作用与顶层平面并发生位移，则按牛顿定律可得到如下方程：F=ηAv/dF——移动顶层平面的力A——沥青薄膜层的面积V——层顶发生位移的速度D——沥青膜的厚度η——沥青的内摩擦系数（反映沥青黏滞性的系数，即绝对黏度）令Τ=F/A，η=v/d，即得到AbsoluteviscosityAbsoluteviscosity(alsocalledcoefficientofviscosity)----isoftenusedtomeasuretheresistancetoflowofaliquid．Itmeasurestheratiobetweentheappliedshearstressandtherateofshear.UnitofabsoluteviscosityPa·s=10Poise泊poise(P):cgs=1g/(cm·s)KinematicviscosityKinematicviscosityisdefinedastheratiobetweentheviscosityandthedensityoftheliquid.expressedinmm2/s,cm2/sorm2/s.1Stoke斯托克

=1cm2/s1centistoke(cSt)=1mm2/s，iscustomarilyused.Viscositytest沥青的黏度随着温度而变化，变化的幅度很大，因此需要采用不同的仪器和方法来测定。VacuumcapillarytubeviscometerCapillarytubeviscometerVacuumcapillarytubeviscometer

为了测定60℃时候的黏度分级，国际上普遍采用真空减压毛细管粘度计测定起动力粘度。

Capillarytubeviscometer

在施工温度135℃下，常采用毛细管法测定其“运动粘度”PenetrationTestIn1888,H.C.BowenoftheBarberAsphaltPavingCompanyinventedtheforerunnertothepenetrationtest,theBowenPenetrationMachine.ThebasicprinciplewastodeterminethedepthtowhichatruncatedNo.2sewingneedlepenetratedanasphaltsampleunderspecifiedconditionsofload,timeandtemperature.

BasicprocedureofpenetrationTestMeltandcooltheasphaltbindersampleundercontrolledconditions.Measurethepenetrationofastandardneedleintotheasphaltbindersampleunderthefollowingconditions:Load=100gramsTemperature=25℃Time=5secondsThedepthofpenetrationismeasuredinunitsof0.1mm(e.g.,iftheneedlepenetrates8mm,theasphaltpenetrationnumberis80).

针入度仪自动针入度仪标准黏度试验标准黏度试验SofteningPoint软化点Thesofteningpoint——isdefinedasthetemperatureatwhichabitumensamplecannolongersupporttheweightofa3.5gsteelball.

PropertiesofAsphalt5.3.1Consistency5.3.2Specificgravity5.3.3Durability5.3.4Ductility5.3.5TemperaturesusceptibilityDefinition:RatioofthemassofasphaltatagiventemperaturetothemassofanequalvolumeofwateratthesametemperatureTestPycnometermethodTemperaturespecified(25°Cor15°C)UseMixdesignanalysis5.3.2SpecificgravitySpecificgravitySpecificgravityvaluesPetroleumasphalts0.95-1.05.Roadtars1.08-1.24.Specificgravitydecreaseswithincreasingtemperature．asphaltcementhasaspecificgravityof1.0atatemperatureof15°C;0.9187at149°C;1.0176at-12°C.PropertiesofAsphalt5.3.1Consistency5.3.2Specificgravity5.3.3Durability5.3.4Ductility5.3.5Temperaturesusceptibility5.3.3DurabilityDurability----canbedefinedasthepropertythatpermitsapavementmaterialtowithstandthedetrimentaleffectsofmoisture，air，andtemperature．ReasonsofagehardeningOxidation:thereactionofoxygenwiththeasphaltbinder.Volatilization:theevaporationofthelighterconstituentsofasphaltbinder.DurabilityAffectedfactorsofanasphalticpavementdurabilitymixdesignpropertiesofaggregatesworkmanshippropertiesoftheasphalt

Measurementofdurabilitythin—filmoventestrollingthin-filmoventestPurposeTosubjectasphalttohardeningconditionsapproximatingthosethatoccurinnormalHMAbatchplantoperationsTestForceddraftoven(325°F)（163℃）Rotatingshelf(5-6RPM)1/8inchfilmofasphaltheatedinpansTime:5hoursWeightlossdetermined(%)ViscosityorpenetrationofTFOTresiduemeasuredThinFilmOvenTest（TFOT）薄膜烘箱试验将50g沥青试样放入不锈钢盛样皿（内径140mm，深9.5-10mm）内，使沥青成为厚约3.2mm的沥青薄膜。沥青薄膜在163±1℃的标准薄膜加热烘箱加热5h后，取出冷却，测量其质量损失，并按照规定方法测定残留物的针入度、黏度、延度等技术指标。PurposeTosubjectasphalttohardeningconditionsapproximatingthoseth