道路工程材料教学课件Road Engineering Materials CH3

RoadEngineeringMaterials

道路工程材料CollegeofAutomobileandTrafficEngineering汽车与交通学院QingdaoTechnologicalUniversity青岛理工大学Ch3LimeandCement3.1Limeandpropertiesoflime3.1.1Limeandproductionsoflime3.1.2Propertiesoflime3.2Cementandpropertiesofcement3.2.1PortlandCement3.2.2Cementchemistry3.2.3Propertiesofcement3.1Limeandpropertiesoflime3.1.1LimeandproductionsoflimeLime-----Inorganicbindingagent无机胶凝材料------Nonhydraulicbindingagent非水硬性胶凝材料Nonhydraulicbindingagent

（air-hardeningbindingagent气硬性胶凝材料)Requiresnowatertotransformitintoasolidproduct.Itcanonlysetsandhardensinair.ProductionsoflimeRoadsub-baseLimestabilizedsoilLimeandcementstabilizedsoilLimeandflyashstabilizedsoilRoadbaseLimeandflyashstabilizedaggregatesLimeandcementstabilizedaggregatesLimemortarManufacturetechnicsoflime

石灰的生产工艺RawmaterialsLimestone石灰石,dolomite白云石,chalkstone白垩，方解石CaCO3（calciumcarbonate）ChemicalreactionCaCO3

CaO+CO2↑（calciumcarbonate）（calciumoxide）（carbondioxide）900℃178kJ/molHydratedlime熟石灰HydratedlimeCaO（calciumoxide）---clumpCa(OH)2（calciumhydroxide）----powder--EnergyChemicalreactionCaO+H2O→Ca(OH)2+64.9kJ/molChemicalingredientofhydratedlimeCa(OH)2HardenedprocessoflimeDrylyhardenedprocess干燥硬化Ca(OH)2+nH2OCa(OH)2·nH2OCarbonizedhardenedprocess碳化Ca(OH)2+CO2+nH2OCaCO3+(n+1)H2Ocrystallizationcarbonation3.1.2Propertiesoflime1、Whatdeterminesthequalityofalimingmaterial?2、Technicalstandardforlime1、Whatdeterminesthequalityofalimingmaterial?（1）PurityCalciumcarbonateequivalentDeterminedinthelaboratory（2）FinenessParticlesizeDrysieveanalysis（1）CalciumCarbonateEquivalent(CCE)orPurityNeutralizingpowerperweightofmaterialrelativetopureCaCO3CaCO3+2H+Ca2++CO2+H2OCa(OH)2+2H+Ca2++2H2O100g/mol74g/molx100=135%CCECCEValues(PurityFactor)（2）Fineness

Relativelimeefficiencyandratewithparticlesize2、TechnicalstandardforlimeIndexEffectivecontentof(CaO+MgO)（有效氧化钙氧化镁含量）Pastequantity产浆量Contentofresidue未消化残渣含量ContentofCO2二氧化碳含量ContentofDissociativeH2O消石灰游离水含量Fineness

细度Technicalstandardforcalciumoxide（建筑生石灰JC/T479-92)ItemCaO(calciumquality)钙质生石灰CaO(magnesiumquality)镁质生石灰First-rate优等品First-class一等品Eligible合格品First-rate优等品First-class一等品Eligible合格品Contentof(CaO+MgO)≥908580858075Contentofresidue≤5101551015CO2(%)≤5796810Pastequantity(L/kg)≥2.82.32.02.82.32.0Technicalstandardforcalciumoxidepowder

(建筑生石灰粉JC/T480-92)ItemCaO(calciumquality)CaO(magnesiumquality)First-rateFirst-classEligibleFirst-rateFirst-classEligibleContentof(CaO+MgO)≥858075807570CO2(%)≤791181012FinenessRemainderofsieve0.9mm(%)≤0.20.51.50.20.51.5Remainderofsieve0.125mm(%)≤7.012.018.07.012.018.0Technicalstandardforhydratedcalciumpowder

(建筑消石灰粉JC/T481-92)Itemhydratedcalciumpowder(calciumquality)hydratedcalciumpowder(magnesiumquality)hydratedcalciumpowder(dolomite)First-rateFirst-classEligibleFirst-rateFirst-classEligibleFirst-rateFirst-classEligibleContentof(CaO+MgO)≥706560656055656055Dissociativewater(%)游离水0.4-2.00.4-2.00.4-2.0Volumeinvariability体积安定性qualifiedqualified-qualifiedqualified-qualifiedqualified-FinenessRemainderofsieve0.9mm(%)≤000.5000.5000.5Remainderofsieve0.125mm(%)≤3101531015310153.2CementandpropertiesofcementCement-----inorganicbindingagentHydraulicbindingagent

（水硬性胶凝材料）Whenthebinderismixedwithwater,chemicalreactionstakeplace,producinghydrateswithgoodadhesiveproperties.3.2.1PortlandCementBydefinition—ahydrauliccementproducedbypulverizingclinkerconsistingessentiallyofhydrauliccalciumsilicates（硅酸钙）,usuallycontainingoneormoreoftheformsofcalciumsulfate（硫酸钙）

asanintergroundaddition.硅酸盐水泥——凡由硅酸盐水泥熟料、0--5％石灰石或粒化高炉矿渣、适量石膏磨细制成的水硬性胶凝材料，称为硅酸盐水泥（即国外通称的波特兰水泥）。普通硅酸盐水泥——凡由硅酸盐水泥熟料、６％--15％混合材料、适量石膏磨细制成的水硬性胶凝材料，称为普通硅酸盐水泥（简称普通水泥）ManufactureofPortlandcementRawMaterialsNecessaryforPortlandCementManufactureMustProvidetheFollowingCalcium钙Silica硅Alumina铝Iron铁CalciumIronSilicaAluminaSulfateAlkaliwasteAragonite文石Calcite方解石Cement-kilndust水泥窑灰CementrockChalk白垩ClayFuller’searth漂白土

Al2O3·4Si02·nH2O

LimestoneMarble大理石Marl泥灰Seashells海贝壳Shale页岩Slag炉渣Blast-furnacefluedustClayIronoreMillscale轧屑OrewashingsPyritecinders黄铁矿渣ShaleCalciumsilicate硅酸钙CementrockClayFlyashFuller’searthLimestoneLoess黄土MarlOrewashingsQuartziteRice-hullashSandSandstoneShaleSlagTraprock

暗色岩Aluminum-orerefuseBauxite矾土CementrockClayCopperslagFly

ashFuller’searthGranodiorite

花岗闪长岩LimestoneLoessOrewashingsShaleSlagStaurolite十字石Anhydrite无水石膏Calciumsulfate硫酸钙Gypsum石膏TraditionalManufactureofPortlandCement1.Stoneisfirstreducedto125mm(5in.)size,thento20mm(3/4in.),andstored.Rawmaterialsaregroundtopowderandblended.or2. Rawmaterialsareground,mixedwithwatertoformslurry,andblended.

3. Burningchangesrawmixchemicallyintocementclinker.Stepsinthetraditionalmanufactureofportlandcement3. Burningchangesrawmixchemicallyintoclinker.Notefourstagepreheater,flashfurnaces,andshorterkiln.Stepsinthemoderndry-processmanufactureofportlandcement.Pyro-Processing4. Clinkerisgroundwithgypsumintoportlandcementandshipped.ClinkerGypsumGrindingClinkerisgroundwithgypsum(calciumsulfate)toproduceportlandcementFinegrindingisnecessaryforhighearlystrength85-95%-325mesh(45microns)~7trillionparticlesperpoundGypsumabsorbswaterandpreventssetting（凝结）

duringshipment3.2.2CementchemistryFourmajorcompoundsofPortlandcementAliteor3CaO•SiO2(Tricalciumsilicate)Beliteor2CaO•SiO2

(Dicalciumsilicate)Aluminateor3CaO•Al2O3

(Tricalciumaluminate)Ferrite

or4CaO•Al2O3•Fe2O3(Tetracalciumaluminoferrite)[‘eilait]硅酸三钙['bi:lait]

硅酸二钙[ə‘lju:mineit]['eilait]ClinkerPhasesAliteor

3CaO•SiO2

orC3SHydrates&hardensquicklyHighearlystrengthHigherheatofhydration(setting)Beliteor

2CaO•SiO2

orC2SHydrates&hardensslowerthanaliteGivesofflessheatHighlatestrength(>7days)ModerncementsaremanufacturedtobehigherinaliteforearlystrengthClinkerPhasesAluminateor

3CaO•Al2O3

orC3AVeryhighheatofhydrationSomecontributiontoearlystrengthLowC3AforsulfateresistanceFerrite

or

4CaO•Al2O3•Fe2O3

or

C4AFLittlecontributiontostrengthLowersclinkeringtemperatureControlsthecolorofcementMicroscopicImagesofClinkerMicroscopicImagesofClinkerAliteMicroscopicImagesofClinkerBeliteMicroscopicImagesofClinker

AluminateMicroscopicImagesofClinker Ferrite3.2.3Propertiesofcement1、Fineness（细度）2、Strengthofcement（强度）3、Consistencyofcement（稠度）4、Setting（凝结）5、Hardening（硬化）1、Fineness

（细度）Finenessofcement----relatestothesizeofthecementgrains.Measure80umsieveSpecificsurface(m2/kg):330-360m2/kgEffectofFinenessHydrationofcementE.g.Fasthardeningcement(increasein7-daystrengthof16%)2、Strengthofcement（强度）StrengthgradeCompressivestrength(MPa)Flexuralstrength(MPa)3d28d3d28dPortlandcement42.517.042.53.56.542.5R22.042.54.06.552.523.052.54.07.052.5R27.052.55.07.062.528.062.55.08.062.5R32.062.55.58.0OrdinaryPortlandcement32.511.032.52.55.532.5R16.032.53.55.542.516.042.53.56.542.5R21.042.54.06.552.522.052.54.07.052.5R26.052.55.07.0StrengthofflyashcementStrengthgradeCompressivestrength(MPa)Flexuralstrength(MPa)3d28d3d28d32.510.032.52.55.532.5R15.032.53.55.542.515.042.53.56.542.5R19.042.54.06.552.521.052.54.07.052.5R23.052.55.07.03、Consistencyofcement稠度Consistencyofcement----isapropertyusedtoestablishthesettingpropertiesofcement.Vicatapparatus

自动水泥维卡仪水泥的施工性能主要有需水性、保水性、流变性、凝结时间等，水泥产品标准中一般只列凝结时间、胶砂流动度，为了测定凝结时间和安定性测定标准稠度用水量。标准稠度用水量

水泥实际使用时绝大多数采用砂浆或砼，而且这些砂浆或砼的流动性各不相同，因此同一水泥在不同情况下使用时凝结硬化情况也不相同。为了建立水泥需水量可比标准和凝结时间的测定基准，采用了标准稠度净浆的概念。在1977年以前我国都用维卡法测定标准稠度用水量，1977年后增加了一种用试锥代替试杆的改进后的维卡仪来测定，它大大简化了标准稠度用水量的测定工作量