3-Mineral Admixtures_ Water & Standards

5/26/2018 3-Mineral Admixtures_ Water & Standards

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Mineral Admixtures & Blended Cements

Primary purposes of adding mineral admixtures or

supplementary cementing materials in concrete To replace cement (economical & technical reasons, and

environmental consideration)

To improve the workability of fresh concrete

To reduce heat and early temperature rise To enhance the durability of hardened concrete

Mineral admixtures are divided into 3 main categories

1. Pozzolanic materials

2. Cementitious materials

3. Non-reactive materials (ground lime stone, silica flour)

May react weakly with cement under certain conditions

Main use, for workability purposes in masonry cements

supplementary cementing materials


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Pozzolanic Materials

History and origins

Greeks: Addition ofnaturally occurringmaterials from volcanicorigin to hydrauliclimes

Romans adopted &extended Greektechnology (e.g.Parthenon)

[Alkali activated binder,e.g. fly ash and/or ggbs]


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Pozzolan

Pozzouli, a town in the Bay of Naples that was the source

of a highly prized deposit of ash from Mt. Vesuvius The name pozzolan is now applied to any alumino-

silicate materials, of either natural or industrial origin

Powder: naturally occurring or to be ground to cement

fineness(Mindess et al 2003)

Rice husk ash (RHA)Palm Oil Fuel Ash (POFA)

Abundant sourcesMuch have been studiedLittle in actual use

WHY?


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Natural Pozzolans

Volcanic ask etc

By-product materials

Fly ashinorganic, non combustible residue of

powdered coal after burning in power plants Silica fumea by-product in the manufacture of Silicon

metal and alloys

Rice husk ashsiliceous residue that remains after the

rice husks are burnt under controlled conditions Calcined clay under controlled temperatures (700-900 oC)

to produce a highly reactive amorphous aluminosilicate(metakaolin)


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Composition

ASTM C 618 for fly ash & natural pozzolans

Class F fly ash (BS EN 450-1: 2005)

produced from bituminous and sub-bituminous coals

(SiO2+Al2O3+Fe2O3) 70% (BS EN 450-1 not less than 70%) Class C fly ash

produced from lignitic coals

(SiO2+Al2O3+Fe2O3) 50%BS EN 450-1: reactive SiO2content at least 25 % by mass

(Mindess et al 2003)Typical CEM l 20 6 3 65


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Composition

Crystalline components (identified by X-ray diffractionmethod)

A good pozzolan shouldhave a high fraction ofreactive glassy oramorphous material

Most pozzolanic materialscontain variousquantities of inertcrystalline phases

Examples

Class F ash: quartz, mullite, hematite, magnetite

Class C ash: free CaO, anhydrite (CaSO4), C3A, C2S, etc

(Mindess et al 2003)Low-calcium fly ashClass FHigh-calcium fly ashClass C


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Composition (contd)

Minor components

Alkali oxides in situations where pozzolanic materials are used to control

AAR, alkali content of the materials should be determined

(BS EN 450-1 Na2O equivalent not to exceed 5.0% by mass)

Unburnt carbon (determined by Loss on Ignition) In SF; 1-2%

In FA: 0.5-3% (sometimes as high as 25%)

In RHA: 3-8%

Concern for air-entrainment

Color of concrete

SO3and periclase (crystalline MgO)

unsoundness


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Physical Characteristics

(Mindess et al 2003)

Note:Surface area > 1 m2/g

(1000 m2/kg)Air permeability not suitable


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silica fume small size packing effect

reduce bleeding, reducethe size of capillary pores

fly ash




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Pozzolanic Reactions Principal reaction: amorphous silica reacts with CH

from cement hydration

CH + S + H C-S-H Composition of C-S-H from pozzolanic reactions

In cases of fly ashes or natural pozzolans: not very differentfrom that formed in regular hydration, C/S is slightly lower

generally In cases on silica fume or rice husk ash, C/S is significantly

different from that of cement hydration, ~1.0

Kinetics of the reaction is similar to the slow rate ofhydration of C2S. Thus, the addition of pozzolan has a

similar effect to higher C2S content in cement Reduce early heat evolution and early strength, but not

long-term strength so long as water is available

Increase the overall solid volume, reduce the porosity,

increase strength and durability


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Pozzolanic Reactions The extent of a pozzolanic reaction can be followed by

monitoring over time the decrease in CH derived from

hydrating of CEM 1

Slow rate of pozzolanic reaction requires prolonged periodof moist curing (particularly for durability of cover concrete)

Pozzolanic reaction is more temperature sensitive thanregular cement hydration (tropical climate beneficial)



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Ground granulated blast-furnace slag (GGBFS)

Obtained from the production of iron

Typical composition CaO = 35-45%, SiO2= 32-38%, Al2O3= 8-16%,

MgO = 5-15%, Fe2O3


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Blended Cements - US

- Setting time

- Strength

- Heat

- Sulfateresistance

Note:

Compare withEN 197-1specifications


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Examples of Cementitious Materials

TYPICAL PROPERTIES OF CEMENTITIOUS MATERIALS

COMPOUNDSPERCENTAGE BY MASS

CEM I GGBS Fly Ash SFCaO 65(63) 40(40) 3(1) [20]# 0.15(0)

SiO2 20(22) 38(35) 50(50) [35]# 92(90)

Al2O3 5(6) 11(8) 28(25) [20]# 0.7(2)

Fe2O3 3.5(3) 0.3(0) 10.4(10) [5]# 1.2(2)Na2O 0.1 0.4 0.7 1.0

K2O 0.7 0.8 2.5 1.5

MgO 0.1 7.5 2.0 0.2

Densitykg/m3

3.13.2 2.9-3.0 2.3-2.6 2.2-2.4

Fineness m2/kg 300400 350600 400 - 700 20,000*

(Data from a different source)

*Approximate value by nitrogen absorption method#[High Lime pfa]

C24


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Mineral AdmixtureEN Standards

Fly Ash: [No SS EN]BS EN 450-1: 2005, Fly ash for concretePart 1: Definition,specifications and conformity criteria

BS EN 450-1: 2005, Fly ash for concretePart 2: Conformityevaluation

Silica Fume [SS EN 13263]

BS EN 13263-1: 2005, Silica fume for concretePart 1: Definitions,requirements and conformity criteria

BS EN 13263-1: 2005, Silica fume for concretePart 2: Conformityevaluation

Ground granulated blast furnace slag [SS EN 15167]BS EN 15167-1: 2006, Ground granulated slag for use in concrete,mortar and groutPart 1: Definitions, specifications and conformitycriteria

BS EN 15167-2: 2006, Ground granulated slag for use in concrete,

mortar and groutPart 2: Conformity evaluation


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Specification for Supplementary Cementitious Materials

Type II Addition

Supplementary Cementitious (or cementing) Materials (SCM)

for Concrete

ground granulated blastfurnace slag (ggbs)

fly ash (includes co-combustion, pulverized fuel ash - pfa)

condensed silica fume (csf) SCM added to Portland cement (CEM I) which provides

calcium hydroxide needed for pozzolanic reaction

Stage 1 Reaction

PC (CEM I) + water ---------> CSH + CH

Stage 2 - Pozzolanic (Secondary) Reaction

SCM + CH + water ----------> CSH

(CSH = calcium silicate hydrates, CH = calcium hydroxide)

Fl A h


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Specification for Supplementary Cementitious MaterialsFly AshBS EN 450 : 2005 Fly ash for concrete

Part 1: Definition, specifications and conformity criteria

Part 2: Conformity evaluation

Fly AshDefinition

Fly ashfine powder of mainly spherical, glassy particles, derived fromburning of pulverised coal, with or without co-combustionmaterials, which has pozzolanic properties and consists

essentially of SiO2and Al2O3, the content of reactive SiO2 asdefined and described in EN 197-1 being at least 25% by massFly ash is obtained by electrostatic or mechanical precipitation of dust-

like particles from the flue gases of furnaces fired with pulverisedcoal, with or without co-combustion materials

Fly ash may be processed, for example by classification, selection,sieving, drying, blending, grinding or carbon reduction, or bycombination of these processes, in adequate production plants.Such processed fly ash may consist of fly ashes from differentsources, each conforming to the definition given in this clause. Ifone or more incoming fly ashes are obtained from co-combustion,then the processed fly ash shall be considered as fly ash fromcombustion

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Fl A h


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Specification for Supplementary Cementitious MaterialsFly Ash

Test CementClause 3.3Selected brand of Portland cement of type CEM I, strength class 42,5 or

higher, conforming to EN 197-1 to be used for carrying out the testsneeded to evaluate conformity to the requirements of 5.3.2 (Activityindex), 5.3.3 (Soundness), 5.3.5 (Initial setting time) and 5.3.6 (Waterrequirement).

Test cement is selected by the fly ash producer and is further

characterised by its fineness and contents of tricalcium aluminateand alkalis as follows:

Fineness (Blaine): At least 300 m2/kg

Tricalcium aluminate: 6% to 12%

Alkalis (Na2O equivalent): 0,5% to 1,2%

Note: Performance with job cement and concrete may be very different,particularly in the case of combination in concrete production,when the Portland cement of type CEM I is not from a singlesource of consistent quality.

[Fly ash not yet available locally, no import without G-to-G agreementon waste across national boundaries, only as pre-blended cements]

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Chemical RequirementsClause 5.2

Chemical composition expressed as proportions by mass of dry fly ashLoss on ignition (EN 196-2, but using ignition time of 1h)

Category A: Not greater than 5,0% by mass

Category B: Between 2,0% and 7,0% by mass

Category C: Between 4,0% and 9,0% by mass

Chloride (EN 196-21 expressed as Cl-ion)

Not greater than 0,10% by mass

Sulfuric anhydride (EN 196-2 expressed as SO3)

Not greater than 3,0% by mass

Free calcium oxide (EN 451-1)Not greater then 2,5% by mass, if > 1,0% conformity to soundnessneeded

Reactive calcium oxide (EN 197-1:2000 method of calculation)

Not to exceed 10.0% by mass, not required if total content of

calcium oxide 10,0%

S ifi ti f S l t C titi M t i l Fl A h


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Chemical Requirements - continued

Silicon dioxide (SiO2) aluminium oxide (Al2O3) and iron oxide (Fe2O3)

(EN 196-2 modified as indicated in 5.2.1)Sum of these not less than 70% by mass, deemed to be satisfiedfor combustion of pulverised coal only

Total content of alkalis (EN 196-21 as Na2O eqv)

Not to exceed 5,0% by massMagnesium oxide (EN 196-2)

Not greater than 4,0% by mass, deemed to be satisfied forcombustion of pulverised coal only*

Soluble phosphate (Annex Cnormative)

Not greater than 100 mg/kg, deemed to be satisfied forcombustion of pulverised coal only*

*Note: Currently, coal fired power generation stations may addmunicipal solid waste as fuel (up to 10% and

more in future) and defined as co-combustion

S ifi ti f S l t C titi M t i l Fl A h


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Physical RequirementsClause 5.3

Fineness (EN 451-2)

Ash retained when wet sieved on a 0,045 mm mesh sieve shallfall within the limits of categories specified below:Category N: 40% by mass 10% of declared valueCategory S: 12% by mass (no tolerance)

Activity index (EN 196-1)

Ratio (in %) of compressive strength of standard mortar bars,prepared with 75% test cement plus 25% fly ash by mass, tocompressive strength of standard mortar bars prepared with100% test cement, when tested at the same ageStandard mortar bar for compressive strength at 28 days and at

90 days

75% and 85% respectivelySoundness (EN 196-3)Expansion determined on 30% fly ash and 70% test cement bymass 10 mmWhere free calcium oxide content of fly ash 10% by mass,requirement deemed to be satisfied

Fl A h


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Physical Requirementscontinued

Particle density (EN 196-6)

Shall not deviate by more than 200 kg/m3 from value declaredby producer

Initial setting time (EN 196-3)Determined on a 25% fly ash plus 75% test cement by masscement paste 120 min longer than initial setting time of a

100% by mass test cement paste that meets requirements inEN 197-1 when test aloneFly ash from combustion of pulverised coal only shall bedeemed to satisfy this requirement

Water requirement (method in Annex B (normative) Method of

determining the water requirement for Category S fly ash95% of that for test cement alone (not required for category N)

Durability RequirementsFly ash conforming to definition in 3.2, fulfilling chemical

requirements in 5.2 and physical requirements in 5.3 deemedto satisfy durability requirements

S ifi ti f S l t C titi M t i l Fly Ash


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Fly AshCurrently there is no fly ash being produced in Singapore, but new

coal fired electricity power plant may be built in the future

Currently fly ash cannot be directly import (classified as a waste)Fly ash may be preblended with CEM I as a blended cement (conforming

to EN 177-1 CEM II/A, CEM ll/B ) and can then be importedOther cement types with fly ash and other supplementary cementitious

materials, e.g. ggbs, limestone powder, may also be used inpreblended cements (CEM IV and CEM V) and can be imported

Durability RequirementsFly ash conforming to definition in 3.2, fulfilling chemical requirements

in 5.2 and physical requirements in 5.3 deemed to satisfydurability requirements

The k-value concept (EN 206-1, Subclause 5.2.5.2) permits type lladditions (fly ash and silica fume) to be taken into account byreplacingwater/cement ratio with water/(cement + k x addition) ratio

[Note: BS 8500 (SS 544) provides alternate specific recommendationsfor different exposure conditions in terms of cement type,

minimum cement content and maximum water-cement ratio]

S ifi ti f S l t C titi M t i l GGBS C31


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Specification for Supplementary Cementitious MaterialsGGBSSS EN 15671 : 2008 Ground granulated blast furnace slag for use in

concrete, mortar and groutPart 1: Definitions, specifications and conformity criteria

Part 2: Conformity evaluationGGBSDefinition

Granulated blastfurnace slagvitrified material made by rapid coolingof a slag melt of suitable composition, obtained by smelting ironore in a blastfurnace, consisting of at least two thirds by mass ofglassy slag and possessing hydraulic properties when suitablyactivated

NOTERapid cooling includes quenching in water (granulation) andprojecting through water and air (pelletisation)

Ground granulated blastfurnace slagfine powder made by grindinggranulated blastfurnace slag

Clause 4ConstituentsThe main constituent shall be granulated blastfurnace slag as defined.

Its chemical composition shall consist of at least two-thirds bymass of the sum of calcium oxide (CaO), magnesium oxide (MgO)and silicon oxide (SiO2). The remainder shall be aluminium oxide

(Al2O3) together with small amount of other components. The ratioby mass (CaO + MgO)/(SiO2) shall exceed 1.0.

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Specification for Supplementary Cementitious Materials GGBS


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Specification for Supplementary Cementitious MaterialsGGBS

Chemical RequirementsClause 5.2

Chemical properties of ground granulated blastfurnace slag shall

conform to the requirements in Table 1Table 1Chemical requirements given as characteristicvalues

Property Test reference Requirements a

magnesium oxide EN 196-2 18 %

sulfide EN 196-2 2.0 %sulfate EN 196-2 2.5 %

loss on ignition, corrected for oxidationof sulfide

EN 196-2 3.0%

chloride b EN 196-2 0.10%

moisture content Annex A 1.0 %a Requirements are given by mass of the ground granulated blastfurnace slagb Ground granulated blastfurnace slag may contain more than 0.10 % chloride

but in that case the maximum chloride content, as a value not to be exceeded,shall be stated on the packages of the documents (see Clause 6)



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Physical RequirementsFineness (EN 196-6)

Specific surface not less than 275 m2/kg

Requirements when combined with test cement

Initial setting time (EN 196-3)Combination (by mass) of 50% ggbs with 50% test cement shall

not be more than twice as long as that of test cement on its own Activity index (EN 196-1)Ratio (in %) of compressive strength of combination (by mass)of 50% ggbs with 50% test cement to the compressivestrength if test cement on its own with water : combination ratio

and water : cement ratio both at 0,50Activity index: at 7 days and at 28 days shall be not less than45% and 70% respectively



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Test CementThe test cement shall conform to EN 197-1 and shall be selected by

the ground granulated blastfurnace slag manufacturer, subject tothe following restrictions:

- CEM I, of strength class 42,5 or higher;

- Blaine fineness shall be at least 300 m2/kg;

- tricalcium aluminate shall be between 6% and 12%;

- alkali (Na2O equivalent) content shall be between 0.5% and 1,2%

(same requirements as test cement for fly ash)

Durability Requirements

GGBs conforming to SS EN 15167-1: 2008 is deemed to satisfydurability requirements, provided that other requirement fordurability of concrete in relevant standards and/or regulationsvalid in the place of use are fulfilled.

The k-value concept (EN 206-1, Subclause 5.2.5.2) covers only type lladditions (fly ash and silica fume) without any provision for GGBS

in a similar manner (see SS 544-1: 2009 for guidance)



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Evaluation of conformity

Initial type testing and factory production control shall be carried outaccording to relevant clauses in EN 15167-2

Conformity shall be continually evaluated on the basis of testing of spotsamples for properties using test methods and minimum testingfrequency for autocontrol testing by manufacturer as specified in Table 2

Statistical criterion: percentile Pk of 10% for required characteristic value oran allowable probability of acceptance CR(consumers risk) of 5%

Conformity shall be verified either by variables or by attributes, as describedin 8.22 and 8.2.3 and as specified in Table 2

The control period shall be 12 months for the routine situation.

Table 2Properties, test methods and minimum testing frequencies forthe autocontrol testing by the manufacturer or his agent and the

statistical assessment procedureMinimum testing frequency: Routine situation and Initial period for a new

GGBSStatistical assessment procedure: Inspection by Variable or by Attributes

for indicated chemical and physical properties

[Use of combination without producers certified conformity data mayneed to verify conformity by userpre-blended cement preferred]


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Slag Hydration

GGBFS reacts slowly with water, strength developmenttoo slow

Activation of slag by

Soluble sodium salts, NaOH, Na2CO3, NaSiO3

Ca(OH)2

Slags are commonly activated by Portland cement

In slag-cement blends, slag also shows pozzolanicbehavior

Products of slag hydration A mixture of C-S-H and AFm (monosulphoaluminate)

The rate of hydration of activated slag is similar to thatof C2S, as is the heat of hydration

Specification for Supplementary Cementitious Materials Silica Fume


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Specification for Supplementary Cementitious MaterialsSilica Fume

BS EN 13263 : 2005 Silica Fume for concretePart 1: Definition, requirements and conformity criteriaPart 2: Conformity evaluation

Definitions

Silica fume (condensed silica fume, microsilica)

very fine particles of amorphous silicon oxide collected as a by-productof the smelting process used to produce silicon metal and ferro-siliconalloys

Silica fume slurry

homogeneous, pH regulated liquid suspension of silica fume in water,typically with a dry content of 50% by mass, corresponding to about700 kg of silica fume per m3of slurry

Densified silica fumesilica fume that has been treated to increase the bulk density by particleagglomeration, the bulk density typically being above 500 kg/m3

Undensified silica fume

silica fume taken directly from the collection filter, the bulk density

typically being in the range 150 kg/m3to 350 kg/m3



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Chemical Requirements

Silicon dioxide (EN 196-2)SiO2 : not less than 85% by mass

Elemental silicon (ISO 9286)Si : not less than 0,4% by mass

Free calcium oxide (EN 451-1)

CaO : not greater than 1,0%Sulfate (EN 196-2)SO3 : not greater than 2,0% by mass

Total content of alkalis (EN 196-2)Na2O equivalent : to be declared

Chloride (EN 196-2)Cl: not greater than 0,3% by mass, if > 1,0% by mass, upper limitfor characteristic value to be declared by manufacturer

Loss on ignition (EN 196-2)by using ignition time of 1 hour, not greater than 4,0% by mass

A48



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Physical Requirements

Specific surface (ISO 9277)

by nitrogen absorption, not less than 15,0 m2/g, (15 000 m2/kg)nor more than 35,0 m2/g (35 000 m2/kg)

Dry mass content in slurry

dry mass content shall not deviate from value declared by

supplier by more than

2% by mass of slurry when determined bydrying a representative sample of at least 5 g of slurry in a wellventilated oven at (105 5) OC to constant mass

Activity index (compressive strength from mortar barsEN 196-1)

ratio (in %) of compressive strength prepared with 80% test

cement plus 10% silica fume per mass of total binder to thatprepared with 100% test cement, when test at the same age andat least 100% when tested at a mortar age of 28 days

S ifi i f S l C i i M i l


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Conformity Criteria

Autocontrol testingbased on testing spot samples by manufacturer for properties,test methods and minimum testing frequencies as specified inTable 1 of EN 13261-1:2005

Conformity criteria for physical and chemical properties and

evaluation procedurebased on spot samples and statistical conformity criteria onthe same basis as for fly ash, either using inspection byvariables or inspection by attributes

[Silica fumein powder or slurry form, product likely to be certified]

[Note: Conformity control for fly ash follows similar approaches as forggbs and silica fume see EN 450-1 and EN 15671 for details]



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Test cement

Selected brand of Portland cement of type CEM I, strength class 42,5 orhigher, conforming to EN 197-1 to be used for carrying the tests

needed to evaluate conformityto the requirement of 5.3.3 inEN 13263-1:2005

Test cement is selected by the silica fume manufacturer and is furthercharacterised by its fineness and contents of tricalcium aluminateand alkalis as follows:Fineness (Blaine): 300 m2/kg to 400 m2/kg (EN 196-6)Tricalcium aluminate: 8% to 12% (EN 196-2)Alkalis (Na2O equivalent): 0,6% to 1,2% (EN 196-2)

The requirements of test cement for silica fume is no t ident ical to thatfor fly ash and GGBS (both with same requirements)

Specification for Supplementary Cementitious Materials Test Cements


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Specification for Supplementary Cementitious Materials Test Cements

Comparison of Test Cements

Test cement requirementsAddition

Fly ash GGBS Silica fumeCEM I, strength class 42,5 or higher 42,5 or higher 42,5 or higher

Blaine finenessm2/kg at least 300 at least 300 300 to 400

Tricalcium aluminate 6% to 12% 6% to 12% 8% to 12%

Alkali (Na2O equivalent) 0,5% to 1,2% 0,5% to 1,2% 0,6% to 1,2%

Note: Test cement for silica fume meets requirements for testing fly ashand GGBS [single test cement for all three preferred]

Cements used as test cements are for conformity testing of additions and

may not be of the same chemical and physical properties as that tobe used in a project.

Initial testing of designed concrete is necessary, unless the particularconcrete has been certified or demonstrated to meet therequirements for the project from inspection records by anaccredited Certification Body (by SAC in Singapore)


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Effects of Mineral Admixtureson Properties of Fresh & Hardening Concrete

Heat of hydration

Reduce the overall heat of hydration

Reduce the rate of heat liberation

Reduce temperature rise in concrete

Workability

Improve cohesiveness

Fly ash and silica fume are particularly beneficial due to theirspherical shape

Addition of fly ash allow w/cm to be reduced while maintaining

slump Silica fume is more beneficial provided that a water reducing

admixture is used (spherical particles provide lubricationamong cement particles; eliminate bleeding and segregation,but make concrete more susceptible to plastic shrinkage)


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Effects on Microstructure

Increase C-S-H & reduce CH leads to more homogenousmicrostructure (CH contributes mainly high pH)

Improve pore structure, reduce overall porosity & poresize



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Effects on Strength Development Develop very good strength over time

May reduce early-age strength, can be offset by reducing

w/cm More reactive pozzolanic materials such as silica fume

and calcined clay will reduce setting time and contributeto early strength


Note:Pozzolanic reactioncontributes to a lotmore strength gainbetween 28 and 56

days than CEM l(control)


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Effects on Drying Shrinkage and Creep

As an approximation, addition of mineral admixtures

does not significantly affect the drying shrinkage orcreep of concrete

However, if volume changes are critical, test should bemade to determine the exact characteristics under the

anticipated service conditions.

[Issues to be covered under hardened concrete]


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Effect on Durability

Used extensively for improving the durability of concrete

Improvements in durability result from the reduction inCH, changes in pore structure, and reduction in w/c

Increase sulfate resistance

Control alkali-aggregate reaction

Reduce chloride diffusion Reduce leaching and efflorescence

EN 206-1 5.2.5.2 k-value concept:

Type II additions to be taken into account by replacing:water/cement ratio with water/(cement + k x addition) ratio in

minimum cement content for durability requirements

BS 8500 (SS 544) for deemed to satisfied approach for differentexposure conditions provides specific minimum cement contentand maximum water/cement ratio directly in relation to specifictypes of cement (i.e. inclusive of k-value concept)


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Linear expansion of concreteexposed to standard ASTM tests forsulphate attack or alkali-aggregate

reaction(More details in topic on aggregates)

Expansion limitfor AAR

Solid lines: w/c=0.5



Note:Better performance with ggbsthan fly ash at commonly usedreplacement rates in both cases

Concrete Constituent Materials Water


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Concrete Constituent MaterialsWater

BS EN 206-1, Mixing water (clause 5.1.4)

Suitability is established for mixing water and for recycled water from

concrete production conforming to EN 1008.

BS EN 1008: 2002 Mixing water for concreteSpecification forsampling, testing and assessing the suitability of water, includingwater recovered from processes in the concrete industry, as mixing

water for concreteThe new standard replaces BS 3148: 1980 and provides more specific

requirements and test methods including water recovered fromprocesses in the concrete industry

Water recovered from processes in the concrete industry shall conformto the requirements of Annex A (normative)

Clause A.4 Requirementsprovides additional requirements to thoseset out in Clause 4 Requirements for all types of water

Constituent Materials for ConcreteWater


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BS EN 1008: 2002 Mixing water for concreteSpecification for sampling, testingand assessing the suitability of water, including water recovered fromprocesses in the concrete industry, as mixing water for concrete

3 Classification of types of water3.1 Portable water

This water is considered as suitable for use in concrete. Such water needsno testing

3.2 Water recovered from processes in the concrete industryThis water, defined in A.2.1, will normally be suitable for use in concrete, but

shall conform to the requirements of Annex A (normative)3.3 Water from underground sources

This water may be suitable for use in concrete, but shall be tested3.4 Natural surface water and industrial waste water

This water may be suitable for use in concrete, but shall be tested3.5 Sea water or brackish water

This water may be used for concrete without reinforcement or otherembedded metal, but is in general not suitable for the production ofreinforced or prestressed concreteFor concrete with steel reinforcement, or embedded metal, the permittedtotal chloride content in the concrete is the determining factor

3.6 Sewage waterThis water is not suitable for use in concrete



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Co c ete Co st tue t ate a s ateClause 4 Requirements

The water shall be examined in accordance with the test proceduresstated in Table 1. (see BS EN 1008, Table 1 for details)

Table 2Maximum chloride content of mixing water (see BS EN 1008,Table 2 for details) or maximum value in concrete in 5.2.7 of EN 206-1Sulphates as SO4

2-shall not exceed 2 000 mg/l.Alkaliequivalent sodium oxide content not normally exceed 1 500 mg/lTable 3Requirements for harmful substances or tests for setting time

and compressive strength (see BS EN 1008 Table 3 for details)Clause 4.4 Setting time and strengthWhen tested in accordance with 6.1.4 the initial setting time obtained on

specimens made with the water shall be not less than 1 hour and notdiffer by more than 25% from the initial setting time obtained onspecimens made with distilled or de-ionised water.

The final setting time shall not exceed 12 hours and not differ by morethan 25% from the final setting time obtained on specimens made withdistilled or de-ionised water.

The mean compressive strength at 7 days of the concrete or mortarspecimens, prepared with the water, shall be at least 90% of the mean

strength of corresponding specimens prepared with distilled or de- ionised water



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Clause 4 Requirements

Table 1Requirements and test procedures for preliminaryinspection of mixing water



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Clause 4 Requirements

Table 2Maximum chloride content of mixing water

Table 3Requirements for harmful substances

End use Max. chloride content mg/l Test procedurePrestressed concrete or grout 500

6.1.3Concrete with reinforcement orembedded metal

1 000

Concrete without reinforcement or

embedded metal

4 500

Substance Maximum content (mg/l) Test procedure

Sugars 100

6.1.3

Phosphates; expressed as P2O5 100

Nitrates; expressed as NO3- 500

Lead; expressed as Pb2+ 100

Zinc; expressed as Zn2+ 100



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Co c ete Co st tue t ate a s ate

Conformity evaluation

The requirements given in this standard are expressed as absolutevalues. For conformity the mixing water shall conform to the

requirements given in Clause 4.

Annex A (normative) Requirements for the use of water recovered fromprocesses in the concrete industry

All water recovered from processes in the concrete industry or

combined water used in concrete shall conform to the requirementsspecified in clause 4 and the following requirements:

Water in storage shall be adequately protected against contamination.Water with a density less than or equal to 1.01 kg/l may be assumed to

contain negligible amount of solid material.

Daily inspection of density of recovered water or combined waterSuitability of recovered water or combined water to Clause 4.

Annex B (informative) Testing scheme for mixing water for concrete(see EN 1008: 2002 for details)

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Comparison of ASTM and BS-EN Standards

ASTM BS-EN

Portland

cement

C 150Spec for Portland

cements

197-1: 2000 (SS EN 197-1: 2008)

CEM IPortland cementBlendedcements

C 595Spec for blendedhydraulic cements

197-1: 2000 (SS EN 197-1: 2008)

CEM IIPortland comp. cement

CEM IIIblastfurnace cement

CEM IVpozzolanic cement

CEM Vcomposite cement

C 1157Performance Specfor blended hydraulic

cements

Mineraladmixtures

C 618Spec for coal fly ashand raw or calcined naturalpozzolans for use in concrete

450-1: 2005 Fly ash for concreteDefinition, spec, and conformitycriteria

C 989Spec for GGBFS for

use in concrete and mortars

15167-1: 2006 (SS EN 15167: 2008)

Ground granulated blast furnaceslag for use in concrete, mortars,and grouts

C 1240Spec for silica fumeused in cementitious

mixtures

13263-1: 2005 (SS EN 13263: 2008)

Silica fume for concrete

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Comparison of ASTM and BS-EN Standards

ASTM BS-EN

Aggregate C 33Spec for concreteaggregates (not includinglightweight, heavyweight,and recycled aggregates)

BS-EN 12620: 2002 (SS EN 12620: 2009)(including natural, manufactured, andrecycled aggregates with density >2000kg/m3)

Admixtures C 494Spec for chemicaladmixtures

C 1017Spec for chemicaladmixtures for flowingconcrete

BS EN 934-2: 2012 (SS EN 934-2: 2009)*

Admixtures for concrete, mortar andgrout

Water C 94Spec for Ready-mixed concrete calls for

test on setting time and 7-day strength of mortar

BS EN 1008: 2002

Mixing water for concrete (including

water recovered from processes in theconcrete industry, as mixing water forconcrete

F rther Reading Optional


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Further Reading - OptionalTopic Mindess et al (2003) Neville (5thEd)

Cement Chapters 3 & 4 Chapter 1

Mineral admixtures Chapter 5 Chapter 2Chemical admixtures Chapter 8 Chapter 5

Water Chapter 6 Chapter 4

Aggregate Chapter 7 Chapter 3

Fresh concrete Chapter 9 Chapter 4

Hardened concrete- responds to stress- Time dependent deformation

Chapter 13Chapter 16

Chapter 6Chapter 9

Hardened concrete- assessment of strength Chapter 14 Chapter 12

Durability Chapter 18 Chapter 10

E- book: Mindess et al : 2003


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E- book: Mindess et al : 2003

Documents

3-Mineral Admixtures_ Water & Standards