L04-GRK_Testing Cement _ Cement Concrete.pdf

Materials Testing, Cement.

1. CONSTRUCTIONANDQUALITY CONTROLOF
FLEXIBLEANDRIGIDPAVEMENTS
LaboratoryTestsonCement,and CementConcrete
National Rural Infrastructure
Development Agency
Ministry of Rural Development
National Institute of Technology
Warangal, Hyderabad

2. Lecture-4
LaboratoryTestsonCement,and CementConcrete

3. PROF.GARJERAJESHKUMAR,NITWARANGAL 3
WhichCementtobeused ???
Nameof the Compound Formula Abbr.
Formula
TricalciumSilicate(Alite) 3CaO. SiO
2 C
3S
DicalciumSilicate(Belite) 2CaO. SiO
2 C
2S
TricalciumAluminate(Celite) 3CaO.Al
2O
3 C
3A
Tetracalciumaluminoferrite(Felite)4CaO.Al
2O
3Fe
2O
3C
4AF
Bogue’sCompounds(Tornebohm)

4. PROF.GARJERAJESHKUMAR,NITWARANGAL 4
HYDRATIONOFCEMENT
Hydration ofC
3S
2C
3S+6H→C
3S
2H
3+3Ca(OH)
2
100+24→75+49
HydrationofC
2S
2C
2S+4H→C
3S
2H
3+Ca(OH)
2
100 +21→ 99+ 22
Calcium-Silicate–Hydrate
C
3S
2H
3(C-S-HGel)
Desirable
CalciumHydroxide
Ca(OH)
2
UnDesirable

5. HydrationofC
3S
•VeryRigorous
•MoreHeatofHydration
•MoreC
3SinHighgrade
cements
•ResponsibleforEarly
Strengthofconcrete
•Quality&QuantityofC-S-H
Gelisinferior/less
•MorequantityofCa(OH)
2
HydrationofC
2S
•LessRigorous
•LessHeatofHydration
•LessC
2SinHighgrade
cements
•Responsible for Later
Strengthofconcrete
•Quality&QuantityofC-S-H
GelisSuperior/more
•Less quantity ofCa(OH)
2
PROF.GARJERAJESHKUMAR,NITWARANGAL 5
WhyCa(OH)
2UnDesirable?
Ca(OH)
2+CO
2→CaCO
3+ H
2O
CaCO
3 Leachesoutaswhitepatches

6. HighGradeOPC–LessDurable!!!
•HighGrade Cementhas moreC
3SandlessC
2S
•QuantityandQuality ofC-S-HGel producedby C
3SisLess
•QuantityofCa(OH)
2producedby C
3Sismore
•C-S-His desirable & Ca(OH)
2isundesirable
•Ca(OH)
2reactswithsulphates(presentinsoils) toformCaSO
4
–this CaSO
4reactswithC
3A(in presence ofwater)–Calcium
SulphoAluminate–Ettringite–Sulphateattack
•Ca(OH)
2isalkaline-pHof 13–prevents corrosionofsteel
PROF.GARJERAJESHKUMAR,NITWARANGAL 6

7. Whatisthesolution?
Blended Cements (PPC)
Ca(OH)
2+SiO
2+H
2O→C-S-H
C-S-Hmuchdense,Inert,impermeable,suitable
formarineconditions.
Limitations -Low Early Strength,
Finalstrengthisequalto morethanOPC
Thisreactionis calledasPozzolanicReaction
ThisSiO
2 comesfrom Pozzolanicmaterials–
Natural or Artificial admixtures –Industrial
wastes(Flyash, GGBFS,SF,RHAetc.,)
PROF.GARJERAJESHKUMAR,NITWARANGAL 7

8. BENEFITSOFBLENDEDCEMENTS(PPC)
Improved Workability,Impermeability,Durability
ResistanceagainstAlkaliAggregateReaction,SulphateAttack,
Carbonation,ChlorideIonPenetration,Chemicalattack
LowHeatofHydration,ThermalShrinkage,LeachingofCa(OH)
2,
Lowcost, LowShrinkage,LowCreep,Lessvulnerabletocracking
Promotesuseofindustrialwastes–Eco friendly–Helpsreduce
pollution–Sustainability
Suitableformarineconstruction,undergroundconstruction
PortlandPozzolanaCement–IS1489(Part-1)2015–Flyashbased
PortlandPozzolanaCement–IS1489(Part–2) 2015-Calcined Claybased
PortlandSlagCement –IS455-1989
PROF.GARJERAJESHKUMAR,NITWARANGAL 8

9. PROF.GARJERAJESHKUMAR,NITWARANGAL 9
WaterRequirementforHydrationofCement
•C
3Srequires24%water&C
2Srequired21%water–Average23%
•23%waterisrequiredforchemicalreaction–BOUNDWATER
•Some waterisimbibedinGel pores–GELWATER
•About15%waterisrequiredtofillup theGelPores–GELWATER
•38%Waterisrequiredforcompletereaction & occupytheGelPores.
•If water is less than 38% -complete hydration is not possible –High
StrengthConcrete(HSC)
•Ifwaterismorethan38%-Gelwillbelessdense–Undesirable–Increase
Permeability-Pronetoearlydeterioration
•Lower water content –Gel will be more dense –Impermeable –Most
Desirable –Unhydrated particles of cement if any (in HSC) will hydrate at a
laterageand fillthecracks–Henceimproveddurability

10. OrdinaryPortlandCementSpecification–IS269-2015
•Table–1–PerformanceImprovers;Table–2–ChemicalRequirementsforOPC
PROF.GARJERAJESHKUMAR,NITWARANGAL 10

11. PROF.GARJERAJESHKUMAR,NITWARANGAL 11
DETAILSOFIS 4031(ALLPARTS)
•PART1DETERMINATIONOFFINENESSBYDRYSIEVING
•PART2DETERMINATIONOF FINENESS BYBLAINEAIR PERMEABILITYMETHOD
•PART3DETERMINATIONOFSOUNDNESS
•PART4DETERMINATIONOFCONSISTENCYOFSTANDARDCEMENTPASTE
•PART5DETERMINATIONOFINITIALANDFINALSETTINGTIMES
•PART 6 DETERMINATION OF COMPRESSIVE STRENGTH OF HYDRAULIC CEMENT OTHER
THANMASONRYCEMENT
•PART7 DETERMINATIONOFCOMPRESSIVE STRENGTHOFMASONRYCEMENT
•PART8DETERMINATIONOFTRANSVERSEANDCOMPRESSIVE STRENGTHOF PLASTIC
MORTARUSINGPRISM
•PART9 DETERMINATIONOFHEATOFHYDRATION
•PART10DETERMINATIONOFDRYINGSHRINKAGE
•PART11DETERMINATIONOFDENSITY
•PART12DETERMINATIONOFAIRCONTENTOF HYDRAULICCEMENTMORTAR
•PART13MEASUREMENT OFWATERRETENTIVITYOFMASONRYCEMENT
•PART14 DETERMINATIONOFFALSESET
•PART15 DETERMINATIONOFFINENESSBYWETSIEVING

12. PROF.GARJERAJESHKUMAR,NITWARANGAL 12
TestingofcementinLaboratory
•StandardConsistencyofCement(IfwaterrequiredisP)
•Initial&FinalSettingtime(Amountofwaterrequiredis0.85P)
•SpecificGravityofcement
•CompressiveStrengthofCement(Amountofwater(0.25P+3)%of (wt
ofcement+ Sand)
•FinenessofCement
•SoundnessofCement(Amountofwater0.75P)

13. StandardConsistencyof Cement
•Amountofwaterrequiredfor preparing the
standardcementpaste.
•The result of this test will be required for the
followingTHREETESTS
•InitialSettingTime &FinalSettingTime
•CompressiveStrengthofCement
•SoundnessTest
•ISCode forVicat’sApparatus–IS5513–1996
•IS Code for Determination of Consistency of
Standard Cement Paste –IS 4031 (Part -4)
1988
•ISCodefor DeterminationofInitial&Final
Settingtime–IS4031(Part5)1988
PROF.GARJERAJESHKUMAR,NITWARANGAL 13

14. FINALSETTINGTIME
Theperiodelapsingbetweenthetimewhenwaterisaddedtothe
cementandthetimeatwhichtheneedlemakesanimpressiononthe
surfaceoftestblockwhiletheattachmentfailstodososhallbethe
finalsettingtime.
PROF.GARJERAJESHKUMAR,NITWARANGAL 14

15. PROF.GARJERAJESHKUMAR,NITWARANGAL 15
COMPRESSIVESTRENGTHOFCEMENT–IS4031(PART6)
•CEMENT+STANDARDSAND(IS650)
•AMOUNTOFWATER(0.25P+3)%BYWT.OFCEMENT+SAND
•STANDARDSANDISAVAILABLE@TAMILNADUMINERALS–TAMIN
•ENNORESAND–ENNOREISABEACHNEARCHENNAI
•CEMENT+SAND1(2mmto1mm)+SAND2(1mmto0.5mm)+SAND3
(0.5mmto0.09mm)=200GMSEACH
•TOTALCEMENT+SAND=800gms
•Amountofwater= (0.25P+3)%of800gms=
•Standardmixing –mouldof50sqcm=7.07cmx7.07cm
•Curingandtestingunderstandardconditions

16. AGGREGATES
•ConcreteisTWOPhasematerial–Paste&Aggregates
•Paste–Cement+Water
•70TO80%OFConcreteisaggregates
•MostlyNaturallyavailable(InFuture-ArtificialAggregates)
•ReduceShrinkageinconcrete
•Reducecost
•SupposedtobeINERT (FewAggarenotINERT–AlkaliAggReaction)
•Importanttoknowthepropertiesofaggregatesresponsiblefor
behaviorinconcrete
PROF.GARJERAJESHKUMAR,NITWARANGAL 15

17. PROF.GARJERAJESHKUMAR,NITWARANGAL 17
Issuesto beStudied
•Classification
•Size
•Source
•Shape
•Strength
•Texture
•SieveAnalysis–Grading
•MoistureContent
•SpecificGravityandBulkDensity
•ThermalProperties
•Bulking Factor
•Soundness
•Cleanliness
•ChemicalProperties

18. PROF.GARJERAJESHKUMAR,NITWARANGAL 18
ClassificationofAggregates
•Natural–RiverSand,Gravel,CrushedRock
•Artificial–BrokenBrick,AircooledSlag,SinteredFlyAsh,Bloated
Clay,Shale,Construction&Demolishedwasteetc.,(C&DWaste)
•Natural–Igneousrocks,Sedimentaryrocks,Metamorphicrocks
•Igneousrocks–Solidificationof moltenrock–Granite,Basaltetc.,
•Sedimentaryrocks–Depositionof weatheredremainsofrocks–
Limestone,Clay,Sandstone,Shale etc.,
•Metamorphicrocks–Transformationofexistingrock–Gneiss,Slate,
Marbleetc.,

19. PROF.GARJERAJESHKUMAR,NITWARANGAL 19
Size ofAggregates
•Largerthesizeofaggregates–lowerthe consumptionof cement,
water,dryingshrinkage–HigherStrengthof Concrete
•Factorsinfluencing–Thicknessofsection,Spacingofreinforcement,
Clear cover,Mixing,handling&Placingtechniques.
•Normallynotmorethan0.25timesthicknessofthemember
•<4.75mm –Fineaggregates,>4.75mm-CoarseAggregates
•Maximumsizeof aggregate–80mm–Normallyusedindams
•Sizeofaggregateis5mmlessthanthespacingofthereinforcement/
ClearCover
•ForRCCnormally –NominalSizeofaggregateshallbe 20mm.

20. SHAPEOFTHEAGGREGATES
PROF.GARJERAJESHKUMAR,NITWARANGAL 20

21. PROF.GARJERAJESHKUMAR,NITWARANGAL 21
Shapeoftheaggregate
•Rounded–Waterworn,Riversands,Desertsands–Lower surface
area-Betterworkability–Nointerlocking–Lowertensilestrength–
Satisfactorycompressivestrength
•Angular–Naturallyirregular–moresurfacearea–Lowerworkability
–Betterinterlocking–bettertensilestrength-Desirable
•Flaky &Elongated–Notdesirable–Notmorethan40%(IS383-2016)
•QuantificationofFlakinessIndex&ElongationIndex
•IS 460-1985-IndianStandardsForTestSeives
•ASTM–AmericanSociety forTestingMaterials

22. TextureofAggregate
RoughTexture–MoreFriction–
Requiresmorepasteforworkability
PROF.GARJERAJESHKUMAR,NITWARANGAL 22
SmoothTexture–LessFriction–
Requireslesspasteforworkability
RoughTexture–Irregular shaped–desirable

23. GradingofAggregate–SieveAnalysis
PROF.GARJERAJESHKUMAR,NITWARANGAL 23
•MinimumPorosityofconcrete
–Topicactiveresearch
•Maximumstrength
•Minimumpermeability–
Maximumdurability
•Minimumconsumptionof
cement–Improvedurability
•Good workability –Good
compactibility –Hence good
strength&durability
•IS383–2016

24. GRADINGOFAGGREGATES
1.IS 460Part1-1985(Reaffirmed1998)SpecificationforTestSieves
2.IS2386(Part–I)–1963(Reaffirmed2003)–Methodsoftestforaggregateforconcrete–Particlesize
andshape
3.IS383–1970(Reaffirmed2002)–Specificationsforcoarseandfineaggregatefromnaturalsourcesfor
concrete
4.Finenessmodulusisthe parameterwhichindicatesthefineness/coarsenessofaggregates
FM of sand preferred for
concrete–3.2to3.5
PROF.GARJERAJESHKUMAR,NITWARANGAL 24

25. StrengthofAggregate
PROF.GARJERAJESHKUMAR,NITWARANGAL 25
If thepasteisweakerthanaggregate–
crackingthroughthepaste–Normal
StrengthConcrete–StrengthDepends
onstrengthofpaste
If thepasteisstrongerthanaggregate
–cracking throughthe aggregate–
HighStrengthConcrete–Strength
Dependson theStrengthofAggregate
ForRoads–Strongeraggregates
ForBuildings–LesserStrengthof
aggregatesis required
Quantifythe StrengthIS2386(PartIV)
1.AggregateCrushingValue
2.10%finesvalue
3.ImpactStrengthofaggregate-Roads

26. PROF.GARJERAJESHKUMAR,NITWARANGAL 26
Strength ofAggregateas perIS 383-2016
•AggregateCrushingValueforaggregatestobeusedforRoads–30
Percent(Maximum)
•AggregateImpactValueforaggregatestobeusedforRoads–30
Percent(Maximum)
•AggregateAbrasionValue(LosAngelesmachine)–30Percent
(Maximum)

27. PROF.GARJERAJESHKUMAR,NITWARANGAL 27
WHATISWORKABILITY?
•Workabilityforconcrete –EASE WITH WHICHTHECONCRETECANBEWORKED
WITH
•WORKING OF CONCRETE –EASE WITH WHICH THE CONCRETE CAN BE MIXED,
TRANSPORTED,PLACED,COMPACTED&FINISHED
•THINMEMBER–SLAB,PAVEMENT,STAIRCASE–LOWWORKABILITY
•BEAMCOLUMNJOINT–REINFORCEMENTISCONGESTED–VERYHIGH
WORKABILITY–SELFCOMPACTEDCONCRETE
•BEAM–NORMALWORKABILITY
•THEORETICALWATERREQUIREDFORCOMPLETEHYDRATIONOFCEMENTIS0.38
(0.23BOUNDWATER+0.15GEL WATER)
•LESSTHAN0.38–SOMECEMENTREMAINSUNHYDRATED–HIGHSTRENGTH
CONCRETE
•MORETHAN0.38–GELISMOREDILUTEANDHAS PORES–REDUCEDURABILITY
•MORTAR/CONCRETE–FA&CA–WILL REQUIREMOREWATERFORLUBRATION

28. PROF.GARJERAJESHKUMAR,NITWARANGAL 28
FACTORSINFLUENCINGWORKABILITY
•WATER/CEMENTRATIO–MOREW/CRATIO–MOREWORKABILITY–
NORMALSTRENGTHCONCRETE
•HIGHSTRENGTHCONCRETE–LESSW/CRATIO–LESSWORKABILITY–
ADMIXTURES(PLASTICISER/SUPERPLASTICISER)TOIMPROVE
WORKABILITY
•SHAPEOFAGGREGATE–ROUNDED–LESSSURFACEAREA–MORE
WORKABILITYFORAGIVENW/CRATIO
•ANGULARAGGREGATE–MORESURFACEAREA–LESSWORKABILITY
FORAGIVENW/CRATIO

29. PROF.GARJERAJESHKUMAR,NITWARANGAL 29
•SURFACETEXTURE–ROUGHTEXTURE–MOREFRICTION–LESS
WORKABILITYFORAGIVENW/CRATIO
•SMOOTHSURFACETEXTURE–LESSFRICTION–MOREWORKABILITY
FORAGIVENW/CRATIO
•GRADINGOFAGGREGATE–WELLGRADEDAGGREGATES–BETTER
WORKABILITY–BETTERCOHESIVITY
•POORLYGRADEDAGGREGATE–POORWORKABILITY–SEGGREGATE/
BLEEDING
•TYPEANDDOSAGEOFADMIXTURES–
•BETTERWORKABILITY–BETTERCOMPACTING–BETTERSTRENGTH–
BETTERFINISH-BETTER DURABILITY
FACTORSINFLUENCINGWORKABILITY

30. PROF.GARJERAJESHKUMAR,NITWARANGAL 30
MEASUREMENTOFWORKABILITY
•SLUMPTEST–Rapidtesting–suitableforsiteconditions
•COMPACTINGFACTOR–Precisetest–Suitableforall concretes
•VEEBEECONSISTOMETER–Suitableforlowworkabilityconcrete
•K-BALLTEST
•FLOWTEST–Veryhighworkableconcrete

31. SLUMPTEST –IS1199
PROF.GARJERAJESHKUMAR,NITWARANGAL 31

32. COMPACTINGFACTORTEST–IS1199
RATIOOF PARTIALLY
COMPACTED CONCRETE
TOFULLYCOMPACTED
CONCRETE
IFTHECONCRETEISWORKABLE
ITWILLGETCOMPACTED
NORMALLY
PROF.GARJERAJESHKUMAR,NITWARANGAL 32

33. VEEBEEDEGREE –VEEBEECONSISTOMETER
•IS1199
•Timeinsecondstotransform
theshapeof theconcretefrom
thefrustumofaconeto
cylindricalshapeismeasured.
•LessWorkability–moretime
•MoreWorkability–Lesstime
PROF.GARJERAJESHKUMAR,NITWARANGAL 33

34. DISCUSSION
•WORKABILITYINCREASESWITH WATERCEMENTRATIO
•SLUMPINCREASESASWORKABILITYINCREASES
•COMPACTINGFACTORINCREASESASWORKABILITYINCREASES
•VEEDEGREEDECREASESWITHTHE INCREASEOFWORKABILITY
PROF.GARJERAJESHKUMAR,NITWARANGAL 34

35. PROF.GARJERAJESHKUMAR,NITWARANGAL 35

36. PROF.GARJERAJESHKUMAR,NITWARANGAL 36
Segregation&Bleedingofconcrete
•Whenworkabilityisveryhigh–constituentsofconcretetendto
segregate.
•Veryhighw/c,impropergradingofaggregates, VeryhighSpecific
Gravityofaggregates
•Morevibrationforhighlyworkableconcretesleadstosegregation
•Iftheconcreteisdroppedfromcertainheight
•If theconcretingisdoneinhotsun–segregationofwater-bleeding
•Whentheconcretesegregates/bleedsandiftheformworkisnot
leakproof–Honeycombedconcrete

37. PROF.GARJERAJESHKUMAR,NITWARANGAL 37
Transportation ofConcrete
•Manualtransport–Ruralareas–littleconcrete–Whentheconcrete
isdroppedfromheight –segregation
•Cranes–Fortwoormorefloors–Trolleysandplacetheconcrete
•Transitmixer–Formoredistances–Retarderstopreventsettingof
concreteduringtransit
•Conveyorbelts –Industries/castingyards
•Formoreheights–Concretepumps–Selfcompactedconcrete

38. Compactionofconcrete
•HandCompaction–PokingorRodding-Crudemethod
-Suitablefor highworkableconcretes–Ruralareas
•PlatformVibrators–Suitableinprefabrication yards&
laboratory
•PanVibrators–suitableforflatsurfaceswithshallow
depths–Slabs, Pavements
•NeedleVibrators–suitablefor compactionatdepths–
beams,columns –Diameterof needle depends on the
spacing between the rebars and thickness of the
member
•ShutteringVibrators–Suitableforverylowworkable
concrete –Effective–suitablefor highstrength
concrete –Goodfinishing–PrecastPSCelements
•Spinning–Centrifugalforces–SuitableforHumepipes
PROF.GARJERAJESHKUMAR,NITWARANGAL 38

39. PROF.GARJERAJESHKUMAR,NITWARANGAL 39
TestingofHardenedConcrete
•IS516–2019–Draftcode
•IS 516 –1959
•DestructiveTesting&NonDestructiveTesting
•NonDestructiveTestingforhumanbeings–X-ray,MRI,BLOOD
PRESSURE,temperaturebythermometer
•PartialDestructiveTestingforhumanbeings–bloodtesting,biopsy,
•Foralreadyconstructedbuilding–Nondestructivetestingorpartially
destructivetesting

40. PROF.GARJERAJESHKUMAR,NITWARANGAL 40
DestructiveTestingofhardenedconcrete
•Concreteisstrongincompression–CompressiveStrength–as perIS
516–150mmx150mmx150mmor100mmx100mmx100mm
•CompressivestrengthasperACI–Cylinderof150mmdia&300mm
height.
•Tensilestrength–Indirectmethod–(1)Splittensilestrengthor(2)
Modulusof rupture

41. PROF.GARJERAJESHKUMAR,NITWARANGAL 41

42. PROF.GARJERAJESHKUMAR,NITWARANGAL 41
COMPRESSIVE
STRENGTH=
P/A

43. Flexural Strength–ModulusofRupture
CONCEPT OF
PUREBENDING
TheoryofBending-
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PROF.GARJERAJESHKUMAR,NITWARANGAL 43

44. SizeofthespecimenasperIS516
100mmx100mmx500mmOR
150mmx150mmx700mm
I=BD
3/12=D
4/12, y=D/2
Z=BD
2/6=D
3/6
P/2
P/2P/2
P/2
P
L/3 L/3L/3 50mm50mm
Whenthe CrackoccursinmiddlethirdportionM=PL/6-??????=
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WhentheCrackoccursat‘a’fromsupportM=Pa/2-??????=
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PROF.GARJERAJESHKUMAR,NITWARANGAL 44
Whena islessthan170mm(for150mmspecimens)or 110mm(for100mm
specimens)theresultsshallbe discarded

45. SplitTensileStrength
CYLINDER 150 mm DIA
&300mm HEIGHT
PROF.GARJERAJESHKUMAR,NITWARANGAL 45

46. SPLITTENSILE
STRENGTH=
2P/LD
PROF.GARJERAJESHKUMAR,NITWARANGAL 46
L=300mm,
D=150mm

47. PROF.GARJERAJESHKUMAR,NITWARANGAL 47
Testingbypartial destruction–coresamples
•Thisispreferredforconstructed&finishedstructure/road/bridge
•Sampleisextractedbycorecutting
•SampleiscylindricalshapeofdifferentH/Dratio
•Cappingisdoneandtestedincompression.
•CorrectionfactorusingFig.1(Pg.No.13)ofIS516-1959
•Correctedcylinderstrengthismultipliedby5/4toequivalentcube
strength
•H/Dratioofthecoreis1.6–Compressivestrengthforcoreis22MPa
•Correctedcylindricalstrength=0.95x22=20.9MPa
•Equivalentcubestrength=(5/4)20.9=26.125MPa.

48. PROF.GARJERAJESHKUMAR,NITWARANGAL 48

49. ULTRASONICPULSEVELOCITYTEST
IS516(Part5/Sec1)2018
Timeinmicroseconds&Distanceinmm–
Velocityinmm/sec= km/sec
HigherVelocityisobtainedwhenthequalityof
concreteintermsofhomogeneity,densityand
uniformity is good –Indirect measure of strength
LowerVelocitymeansmorevoids,lessdensity,
honeycombedconcrete orexistenceof cracks
PROF.GARJERAJESHKUMAR,NITWARANGAL 49
aggregateandcement
Calibrationcurvesforaparticulartypeof
istobeestablished.
Calibrationcurvesarenotuniversallyvalid

50. PROF.GARJERAJESHKUMAR,NITWARANGAL 50