CONSTITUENTS AND CONSTITUENTS AND APPLICATIONS IN APPLICATIONS IN

CONCRETECONCRETE

CONSTITUENTS OF CONCRETECONSTITUENTS OF CONCRETECementCementWaterWaterSand (Fine Aggregate)Sand (Fine Aggregate)Coarse AggregateCoarse AggregateChemical AdmixturesChemical AdmixturesMineral AdmixturesMineral Admixtures

CEMENTSCEMENTSOPC(33 grade,43 grade,53 grade)OPC(33 grade,43 grade,53 grade)

PPC (33 grade)(15-35% flyash)PPC (33 grade)(15-35% flyash)

PSC (33 grade)(25-70% slag)PSC (33 grade)(25-70% slag)

CEMENT STRENGTHCEMENT STRENGTH 43 grade cement43 grade cement 3-Day strength-23MPa,Min.3-Day strength-23MPa,Min. 7-Day strength-33 MPa,Min.7-Day strength-33 MPa,Min. 28-DAY strength-43 MPa,Min.28-DAY strength-43 MPa,Min.

53 grade cement53 grade cement 3-Day strength-27MPa,Min.3-Day strength-27MPa,Min. 7-Day strength-37MPa,Min.7-Day strength-37MPa,Min. 28-Day strength-53MPa,Min. 28-Day strength-53MPa,Min.

IMPORTANT PROPERTIESIMPORTANT PROPERTIESOF CEMENTOF CEMENT

Fineness(Blaine’s ),cmFineness(Blaine’s ),cm22/gm,Setting /gm,Setting timetime

Compressive strengthCompressive strengthHeat of hydration, Calories/gm or Heat of hydration, Calories/gm or

KJ/KgKJ/Kg 1calory = 4.187 Joules1calory = 4.187 JoulesAlkalis(NaAlkalis(Na22O, KO, K22O)O) NaNa22O Equiv.(%)=NaO Equiv.(%)=Na22O(%) O(%)

+0.658K+0.658K22O(%)O(%) Low Alkali OPC:<0.6%alkali as NaLow Alkali OPC:<0.6%alkali as Na22O O

Equiv.Equiv.

Typical Data On Heat of Typical Data On Heat of HydrationHydration

of Cementsof CementsCement Cement Heat of hydration,KJ/KgHeat of hydration,KJ/Kg At 7 daysAt 7 days At 28 daysAt 28 daysOPC(43 grade) 280 321OPC(43 grade) 280 321

PPC (i) 190 (i)225PPC (i) 190 (i)225 (ii) 185 (ii)227(ii) 185 (ii)227PSC(Market samples) (i)185 (i)230PSC(Market samples) (i)185 (i)230 (ii)171 (ii)238(ii)171 (ii)238 (iii)191 (iii)243(iii)191 (iii)243Low heat PortlandLow heat PortlandCement(IS:12600) 272(Max) 314(Max)Cement(IS:12600) 272(Max) 314(Max)

TYPICAL DATA ON ALKALITYPICAL DATA ON ALKALIOF OPCOF OPC

NaNa22OO K K22OO Total Alkalies(%) Total Alkalies(%) asas

(%) (%) (%) (%) NaNa22O EquivO Equiv..1.1. 0.24 0.54 0.590.24 0.54 0.592.2. 0.25 0.53 0.59 0.25 0.53 0.59 3.3. 0.49 0.73 0.97 0.49 0.73 0.97 4.4. 0.66 0.90 1.250.66 0.90 1.255.5. 0.35 0.93 0.960.35 0.93 0.966.6. 0.16 1.15 0.910.16 1.15 0.917.7. 0.16 0.55 0.52 0.16 0.55 0.52

LOSSLOSS OF STRENGTH OF OF STRENGTH OF CEMENT WITH TIMECEMENT WITH TIME

CEMENT STORED IN NORMAL CEMENT STORED IN NORMAL WEATHER-PROOF SHEDS WEATHER-PROOF SHEDS Loss of StrengthLoss of Strength 3 Months ---- 20%3 Months ---- 20% 6 Months ---- 35%6 Months ---- 35% 2 Years -----50%2 Years -----50%

TYPICAL PHYSICAL TEST TYPICAL PHYSICAL TEST RESULTS RESULTS

OF OPC AND PSCOF OPC AND PSC OPCOPC PSC PSC (43 grade) (43 grade)

1.Fineness,m1.Fineness,m22/kg 281 289/kg 281 2892.Setting time:2.Setting time: Initial: 45min. 100min.Initial: 45min. 100min. Final: 90min. 165min.Final: 90min. 165min.3.Com.strength,N/mm3.Com.strength,N/mm22

@ 3 days 33.5 24.5@ 3 days 33.5 24.5 @ 7 days 41.5 33.0@ 7 days 41.5 33.0 @ 28days 54.0 43.0@ 28days 54.0 43.0

WATERWATERMixing and curing water should be ofMixing and curing water should be of good quality.good quality.Potable water is generally consideredPotable water is generally considered satisfactory for mixing concrete.satisfactory for mixing concrete.The pH of water shall be not less than 6.The pH of water shall be not less than 6.Mixing or curing of concrete with sea Mixing or curing of concrete with sea water is not recommended, because ofwater is not recommended, because of harmful salts in sea water.harmful salts in sea water.Under unavoidable circumstances,sea waterUnder unavoidable circumstances,sea water may be used for mixing or curing of plain may be used for mixing or curing of plain

concrete.concrete.

TYPICAL CHEMICAL TEST TYPICAL CHEMICAL TEST RESULTS(%) 0F OPC,SLAG &PSCRESULTS(%) 0F OPC,SLAG &PSC

OPC OPC SLAGSLAG PSC PSC1.Loss on ignition 1.39 -- 0.28 1.Loss on ignition 1.39 -- 0.28 2.Silica (SiO2.Silica (SiO2) 2) 21.65 33.87 27.68 21.65 33.87 27.683.Alumina(Al3.Alumina(Al22OO33) 5.46 19.71 12.59) 5.46 19.71 12.594.Iron Oxide(Fe4.Iron Oxide(Fe22OO33) 3.06 0.41 1.92) 3.06 0.41 1.925.Calcium Oxide 63.00 33.34 47.635.Calcium Oxide 63.00 33.34 47.636.Magnesia(MgO) 1.66 10.61 5.516.Magnesia(MgO) 1.66 10.61 5.517.Sulphuric Anhyd7.Sulphuric Anhyd -ride (SO-ride (SO33) 2.14 0.08 0.95) 2.14 0.08 0.958.Insoluble Residue 0.29 0.50 0.468.Insoluble Residue 0.29 0.50 0.469. Chloride 0.026 0.016 0.0169. Chloride 0.026 0.016 0.01610.Sulphide sulphur 0.2210.Sulphide sulphur 0.22

FLYASH (GOOD QUALITY)FLYASH (GOOD QUALITY) 1.Fineness(Blaine’s),Min.3200 cm1.Fineness(Blaine’s),Min.3200 cm22/gm/gm 22.Lime Reactivity,Min.4.5 MPa.Lime Reactivity,Min.4.5 MPa 3.Loss on Ignition,Max.5%3.Loss on Ignition,Max.5% (1000(10000 0 C)C)

SiOSiO2 2 +Ca(OH)+Ca(OH)22=Calcium Silicate=Calcium Silicate (lime) Hydrate (lime) Hydrate (Strength giving (Strength giving compound in concrete)compound in concrete)

So,when we use PPC or flyash in So,when we use PPC or flyash in concrete,pozzolanic reaction takesconcrete,pozzolanic reaction takes place between flyash and the limeplace between flyash and the lime [ Ca(OH)[ Ca(OH)22]] liberated due to the liberated due to the hydrationhydration of OPC.of OPC. Similar pozzolanic reaction takes Similar pozzolanic reaction takes placeplace when we use slag(g.g.b.s) or PSC when we use slag(g.g.b.s) or PSC in in concrete.concrete.

BENEFICIAL EFFECT OFBENEFICIAL EFFECT OFFLYASH AND G.G.B.SFLYASH AND G.G.B.S

Fresh concrete has improved workability.Fresh concrete has improved workability.The heat development is slower,and soThe heat development is slower,and so the peak temperature inside the the peak temperature inside the concrete is lower.concrete is lower.The result is a denser microstructureThe result is a denser microstructure of the hydrated cement paste andof the hydrated cement paste and hence,improvement in the long-termhence,improvement in the long-term strength & enhanced durability of strength & enhanced durability of

concrete.concrete.

TYPICAL TEMPERATURE- RISETYPICAL TEMPERATURE- RISEOF CONCRETE WITH PSCOF CONCRETE WITH PSC

Rise in temp.over initial Rise in temp.over initial temptemp.. PSC PSC PSC PSCPSC PSC PSC PSC Slag - (65%) (60%) (54%) (50%) Slag - (65%) (60%) (54%) (50%)

Max. temp.Max. temp. rise,rise,00c 22.0 22.7 23.0 c 22.0 22.7 23.0 20.5 20.5 @ 48hr @43hr @47hr @ 48hr @43hr @47hr @47hr @47hr

APPLICATIONS OF CEMENTSAPPLICATIONS OF CEMENTS WHICH CEMENT TO BE USED & WHERE?WHICH CEMENT TO BE USED & WHERE?

OPC(43grade), PPC,PSCOPC(43grade), PPC,PSC—All purpose —All purpose cement.cement. (In normal buildings and structures)(In normal buildings and structures)OPC(33grade)OPC(33grade) can be used in lower grades can be used in lower grades of concrete(say,M10,M15,M20grades etc.)of concrete(say,M10,M15,M20grades etc.) OPC(53grade):OPC(53grade): For high strength For high strength concrete.e.g inconcrete.e.g in bridge girders,prestressed concrete bridge girders,prestressed concrete railwayrailway sleepers etc.sleepers etc.

IN AGGRESSIVE IN AGGRESSIVE ENVIRONMENTSENVIRONMENTS

For aggressive environments,we preferFor aggressive environments,we prefer blended cements( PPC or PSC).blended cements( PPC or PSC).When there is SOWhen there is SO33 in soil & ground in soil & ground water,water, Low CLow C33A (<5%) sulphate-resistingA (<5%) sulphate-resisting cement should be used.cement should be used.When both SOWhen both SO3 3 & Cl are & Cl are there :OPC(withthere :OPC(with 5-8% C5-8% C33A or PSC(with>50% slag) isA or PSC(with>50% slag) is required to be used.required to be used.

IN AGGRESSIVE IN AGGRESSIVE ENVIRONMENTSENVIRONMENTS

Low alkali(<0.6% alkali as NaLow alkali(<0.6% alkali as Na22O Equiv.)OPC O Equiv.)OPC is to be used in concrete dams & in otheris to be used in concrete dams & in other Hydraulic structures(e.g.in Tunnel linings,Hydraulic structures(e.g.in Tunnel linings, Power Houses,Spillways etc.),because inPower Houses,Spillways etc.),because in Himalayan regions,aggregates may be Himalayan regions,aggregates may be reactive.reactive. Use of flyash(at least 20%) or slag(at Use of flyash(at least 20%) or slag(at leastleast 50%) along with low alkali OPC will50%) along with low alkali OPC will be advantageous,in such cases.be advantageous,in such cases.

MASS CONCRETE MASS CONCRETE STRUCTURESSTRUCTURES

In mass concrete structures (massiveIn mass concrete structures (massive structures: size >1m),OPC(33grade) willstructures: size >1m),OPC(33grade) will be preferred for low grade (say M15) be preferred for low grade (say M15) concrete (eg.concrete dam),because ofconcrete (eg.concrete dam),because of low heat of hydration in this cement.low heat of hydration in this cement. PPC or PSC can also be used. PPC or PSC can also be used. Because of low heat of hydration,theBecause of low heat of hydration,the temperature rise inside the concretetemperature rise inside the concrete will be less.will be less.

TYPICAL APPLICATIONSTYPICAL APPLICATIONS Use of 43 grade OPCUse of 43 grade OPC:: In RMC plants( 43grade OPC+ In RMC plants( 43grade OPC+ Flyash).Flyash). In concrete roads(M40 grade of In concrete roads(M40 grade of concreteconcrete for National Highways, M30 grade of for National Highways, M30 grade of concrete for Rural roads).concrete for Rural roads). Use of 53 grade OPCUse of 53 grade OPC:: In high strength In high strength concrete(M50,M60,M70concrete(M50,M60,M70 and M80)and M80)

USE OF 53 USE OF 53 GRADE OPCGRADE OPCIn prestressed concrete railway In prestressed concrete railway sleepers(M50 grade concrete).sleepers(M50 grade concrete).In Delhi Metro precast segments(M50 In Delhi Metro precast segments(M50 grade concrete), bridge piers(M60grade concrete), bridge piers(M60 grade of concrete, bridge pedestalsgrade of concrete, bridge pedestals (M70 grade of concrete) over river (M70 grade of concrete) over river

Yamuna.Yamuna. Terhi dam Spillway(M60 grade of Terhi dam Spillway(M60 grade of

concrete).concrete).Kol dam Spillway( M80 grade of Kol dam Spillway( M80 grade of

concrete).concrete).

USE OF (OPC + FLYASH)USE OF (OPC + FLYASH) In Ready Mixed Concrete Plants.In Ready Mixed Concrete Plants. Delhi Metro Underground Bottom Delhi Metro Underground Bottom

SlabsSlabs (M35 grade concrete)(30% (M35 grade concrete)(30%

flyash+OPC).flyash+OPC). In Ropar (Punjab ) concrete roadsIn Ropar (Punjab ) concrete roads (M40 grade concrete using 50% (M40 grade concrete using 50%

flyash).flyash).

USE OF SLAG OR PSCUSE OF SLAG OR PSC In concrete Pile cap in Durgapur steelIn concrete Pile cap in Durgapur steel plant modernisation project(M40 gradeplant modernisation project(M40 grade concrete).concrete). In Bandra(Mumbai) sewage disposalIn Bandra(Mumbai) sewage disposal pipe line(OPC 53-grade+70% slag used)(M45 pipe line(OPC 53-grade+70% slag used)(M45

grade).grade). In marine jetty at Ennore(Tamil Nadu)(M35 In marine jetty at Ennore(Tamil Nadu)(M35

&M40).&M40). In M40 grade Petronet concrete piles atIn M40 grade Petronet concrete piles at Dahej(Gujarat). Dahej(Gujarat). In concrete dam(100m high) at KoteshwarIn concrete dam(100m high) at Koteshwar (in Uttarakhand)( PSC with 55% slag was used).(in Uttarakhand)( PSC with 55% slag was used).

USE OF SLAG & FLYASHUSE OF SLAG & FLYASHIn a cable stayed bridge at In a cable stayed bridge at

sea(Norway) (PSC was used for sea(Norway) (PSC was used for M70 grade concrete)M70 grade concrete)

In the twin towers at KualalumpurIn the twin towers at Kualalumpur (OPC+PFA)was used for M80 grade(OPC+PFA)was used for M80 grade concrete).concrete).In Euro tunnel (M30 grade concrete),In Euro tunnel (M30 grade concrete), ( OPC + slag +flyash) were used.( OPC + slag +flyash) were used.