Mic
rosi
lica
600
High Strength Concrete
A Natural Pozzolan for High Performance Concrete
Mic
rosi
lica
600
Thinner Elements •Lowermaterialscost •Reducedelementweight •Reducedheatbuildup •Increaseduseablespace •Opportunitiesformoreelegantdesigns
Improved Element Properties •Lesscolumnshortening •Reducedcreep
Reduced Reinforcement •Lowermaterialcost •Fasterconstruction •Simplifiedrebarplacing •Lowerrebarfixingcost •Lessrebarcongestion–improvement concretecompaction
Enhanced Concrete Properties •Betterpumpability •Lowerheatgeneration •Betterformfinish
MICROSILICA 600 — for High Strength Concrete Highstrengthconcrete(HSC)provideseconomicbenefitsthroughthinner(lighter)constructionelementsandreducedconstructiontimes.
Strengthsof100MPaarebeingachievedbyreadymixconcretesuppliersthroughtheuseofMicrosilica600.
NewZealandConcreteDesignStandard–NZ3101,limitstheuseofhighstrengthconcrete.Asbrittlenessincreaseswithstrength,seismicdesignrequirementslimitcompressivestrengthto70MPaforductilestructuresandstructuresoflimitedductility.Otherstructurescanbedesignedusingconcretestrengthsofupto100MPa.
Theuseofhighstrengthconfinementsteel,besidesreducingthecongestingoftransversereinformcementaroundcolumnsandbeamjoints,greatlyimprovestheductilebehaviour.
Table 1. Comparative cost of columns using HSC and normal concrete
Benefits of Microsilica 600 Concrete EconomicsTheuseofMicrosilica600inHSCleadstoeconomicalandfasterconstruction.
GeneralWhereverconcreteelementsareincompression,higherstrengthconcretewillresultinreducedmaterialcost.
Inadditionthereareotherindirectcostsavingswhichcanbesignificant.Thinnertunnelliningsleadtosavingsinexcavation.Lighterstructuresresultsinreducedfoundationrequirements.
Precast ConcreteForpreciseconcreteelements,onsitecartagedemandsarelessened.Transportcostsarereduced.
ColumnsCostanalysiscarriedoutbytheNZCement&ConcreteAssociation(table1)showthatbyincreasingconcretestrengths,financialsavingscanbeachieved.
ItemConventional600mmx500mm40MPaConcrete
HSCOption450mmx450mm70MPaConcrete
Savings
Concrete $8400 $6660 $1740
Reinforcement
Longitudinal $7129 $3210 $3910
Transverse $13360 $9340 $8004
Formwork $23760 $19440 $4320
Total $52640 $38650 $13990
Savings 26.6%
Mic
rosi
lica
600
Physical Properties
Compressive StrengthThepozzolanicreactivity,finepowderpackingmechanismandtheimprovementofbondattheaggregatepasteinterfaceincreasesthestrengthofMicrosilica600concrete.
Laboratorytestseries(Figure1)carriedoutoverayearusingcommerciallyavailableaggregatesandsand,producedaverageresults10%higherthanthoseachievedusingjustPortlandCement.
TheefficiencyofMS600dependsonmanyfactors.Generally,however,Microsilica600doesnotdecrease 7daystrengthsandsignificantincreasesincompressivestrengthofconcreteareobtainedby21days.
Theincreaseinstrengthisinlinewiththelevelsofefficiencyasreportedinthe“GeneralMicrosilica600”brochure.
Drying Shrinkage
Atthesamewater/binderratiothereislittledifferenceinthelongtermshrinkagecharacteristicsofMicrosilica600concreteandstandardconcrete(Figure3).Althoughwatercontentisrecognizedasbeingthemajorcontributortoconcretedryingshrinkage,aggregateandsandpropertiesalsoinfluencetheperformance.
ExtensivetestscarriedoutusingaggregatesandsandssourcedfrommajorNewZealandquarriesproducedawiderangeofshrinkagevalues(figure3).
Figure 1. Strength improvement. In this case 28 day strength increased by 10% but increases of
up to 20% are possible.
Figure 3. Shrinkage of Microsilica 600 concrete is similar to conventional concrete.
Strength Improvement
0102030405060708090
0 20 40 60 80 100
Time in Days
Stre
ngth
MPa
8% MS600Control
Drying Shrinkage
0100200300400500600700
0 20 40 60Time in days
400-control
400-7% MS 600
400-10% MS600
Drying Shrinkage
0
200
400
600
800
1000
0 20 40 6
Time in days
Min values
Max values
0
Figure 4. Concrete shrinkage values over time. The influence of aggregate and sand on the shrinkage
properties 10% MS600 dosage.
Figure 3. High strength concrete (105 MPa at 28 days) used for these bridge beams had a release strength after
steam curing (heat maturity 620° CH) of 60 MPa.Whangamarino River Bridge Beams, NZ
Mic
rosi
lica
600
Tensile Strength
Improvedaggregatetopastebondingpropertiesincreasetheconcrete’sinherenttensilestrength.Relativetocompressionstrength,thetensilestrengthofMicrosilica600concreteisgreaterthanconventionalconcrete.
Modulus of Elasticity
ExtensivetestswerecarriedoutonaggregatesobtainedfromfivemajorNewZealandquarries.
Asshownintable2withintherangeofstrengthsconsidered,Microsilica600impactslittleontheModulusofElasticity.Geologicalpropertiesofthecoarsefractionoftheconcreteaggregatesdidinfluenceperformance.
Table 2. Relationship between strength and Modulus of Elasticity.
Figure 6. MS600 was used in concrete for high strength columns,
reducing their size and giving increased usable area.
Figure 5. Microsilica 600 increases the tensile to
compressive strength ratio.
MICROSILICA 600 APPLICATIONS & INFORMATION
Product NoteThe information contained in this brochure is offered in good faith and every effort has been made to ensure its accuracy. However, due to differences in conditions, environments and materials no liability is accepted by Microsilica NZ, Golden Bay Cement or their agents for loss or damage, direct or otherwise, resulting from the application of the information contained herein. Microsilica NZ reserves the right to change product specification without prior notice
MICROSILICANZ POBox1359,ShortlandSt,Auckland1140, NewZealand.Ph6473454710. [email protected]
OtherMicrosilica600applicationsforspecialistconcretesandhighperformanceconcretearedetailedinthefollowingbrochures: •Industrial&CommercialFloors •ChemicalResistantConcrete •WaterproofConcrete •MarineConcrete •Shotcrete
Referenceshouldalsobemadetotheoperationalandsafetyrequirementsinthefollowingdocuments: •Health&SafetyDataSheet •ConcreteMixingInstructions •ConcretePlacement&FinishingProcedures •PlasticPropertiesofMicrosilica600Concrete
Strength MOE
MPa GPa
Control 59 42.4
5%MS600 65 42.1
10%MS600 68 41.5
Tensile/Compression Strength
01234567
0 50 100
Compressive Strength MPa
Tens
ile S
tren
gth
Mpa
Springleaf Towers, Singapore
Top Related