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IS 15388:2003

Indian StandardSILICA FUME SPECIFICATION

ICS91.100. I5

0 BIS 2003

BUREAU OF INDIAN STANDARDSMANAK BHAVAN, 9 BAHADUR SHAH ZAFAR MARGNEW DELHI 110002

August 2003 Price Group 4

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Cement and Concrete Sectional Committee, CED 2

FOREWORDThis Indian Standard was adopted by the Bureau of Indian Standards, after the draft finalized by the Cement andConcrete Sectional Committee had been approved by the Civil Engineering Division Council.Si I ica fume is very fine pozzolanic material composed of ultra fine, amorphous glassy sphere (average diameter,0.10-0. 15~m) of silicon dioxide (Si02) produced during the manufacture of silicon or ferro-silicon by electricarc furnaces at temperature of over 2 000C. The micro silica is formed when SiO gas produced in the furnacemixes with oxygen, oxidizes to Si02, condensing into the pure spherical particles of micro silica that form themajor part of the smoke or fume from the furnace. These fumes are collected and bagged called silica fume. It isalso known as condensed silica fume and micro silica. The Committee also felt that chloride content in silicafume shall be declared by the manufacturer so that different samples of silica fume can be compared and Engineer-in-Charge is in knowledge of the amount of chloride entering into concrete through silica fume.This standard has been formulated to fulfil the need for a specification for this material, in view of its increasinguse in the country.[n the preparation of this standard, due weightage has been given to the international coordination among thestandards and practices in different countries in addition to relating it to the practices in the field in this country.For this, assistance has been derived from the following:

a) ASTM C 1240-2000 Standard specification for use of silica fume as a mineral admixture in hydrauliccement concrete, mortar and grout; issued by the American Society for Testing and Material

b) EN 197-1:2001 Cement Part 1: Composition, specifications and conformity criteria for commoncements

The composition of the Committee responsible for formulation of the standard is given at Annex B.For the purpose of deciding whether a particular requirement of this standard is complied with, the final value,observed or calculated, expressing the result of a test, shall be rounded off in accordance with IS 2: 1960 Rulesfor rounding off numerical values (revisecf). The number of significant places retained in the rounded off valueshou]d be the same as that of the specified value in this standard.

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IS 15388:2003

Indian StandardSILICA FUME SPECIFICATION

1 SCOPEThis standard covers the chemical and physicalrequirements of silica fume for use in concrete andother systems containing hydraulic cement.2 REFERENCESThe following standards contain provisions whichthrough reference in this text, constitute provisions ofthis standard. At the time of publication, the editionsindicated were valid. All standards are subject torevision and parties to agreements based on thisstandard are encouraged to investigate the possibilityof applying the most recent editions of the standardsindicated below.

[S No. Title1727:1967 Methods of test for pozzolanic

materials (@W revision4082:1996 Recommendations on stacking and

storage of construction materials andcomponents at site (second revision

4305:1967 Glossary of terms relating topozzolana

6491:1972 Methods of sampling fly ash3 TERMINOLOGY3.0 For the purpose of this standard, the definitionsgiven in IS 4305 and the following shall apply.3.1 Silica Fume Very fine pozzolanic material,composed mostly of amorphous silica produced byelectric arc furnaces as a byproduct of the productionof elemental silicon or ferro-silicon alloys.3.2 Silica Fume in Natural State Silica fume takendirectly from the collection filter. The bulk densitytypically being in the range of 150-350 kg/m3.3.3 Densitied Silica Fume Silica fume that has beentreated to increase the bulk density by particleagglomeration. The bulk density typically being above500 kg/m3.3.4 Silica Fume Slurry A homogeneous, liquidsuspension of silica fume particles in water, typicallywith a dry content of 50 percent by mass,corresponding to about 700 kg/m3 of silica fume.4 CHEMICAL REQUIREMENTSSilica fume shall conform to the chemical requirementsgiven in Table 1.

Table 1 Chemical RequirementsClause 4)

s ] Characteristic Requirements TestMethod

N 2 3 4i SiOz , percentbymass, 85.0 IS 1727

Minii) Moisture content, percent 3 .0 see

by mass, Max Note 1iii) Loss on ignition, percent 4.0 1S 1727

by mass, J xiv) Alkalies as NalO, percent, 1.5 See

Max Notes2 and 3

NOTES1 For determination of moisture content, dry a weighed sampleas received to constant mass in an oven at 105C to 11OC.Express in percentage, the loss in mass and record as moisturecontent.Z Requirement of limiting alkali shall be applicable in casesilica fume is to be used in concrete containing reactiveaggregate.3 For determination of alkalies, method of test used fordetermination of this in cement maybe adopted.

5 PHYSICAL REQUIREMENTSSilica fume shall conform to the physical requirementsgiven in Table 2.6 SAMPLING AND CNTERIA FOR CONFERMfTY6.1 Sampling6.1.1 The methods and procedure of sampling of silicafume shall be same as the method given for fly ash inIS 6491. All samples whether grab or composite shallhave amass of at least 1 kg. Two grab/~omposite samplesshall be taken from the lot for the first 100 t of silicafume. For each subsequent 100 t from the lot of silicafi.tme, one sample shall be taken. However, not less thantwo samples shall be taken in any sampling programme.6.1.2 The sample or samples for the purpose of testingmay be taken by the purchaser or his representative orby any person appointed to supervise the work for thepurpose of which the silica fume is required or by thelatters representative.6.2 Criteria for Conformity6.2.1 The samples of silica fume drawn in accordancewith 6.1 and then prepared as per 7 and shall be testedas per 4 and 5.

1

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IS 15388:2003Table 2 Physical Requirements

Clause 5

SI Characteristic Requi~e- Method ofNo. ment Test, Ref to

r -Annex IS

No.1 2 3 4 5i Specific surface m:/g, 15 A

Mirf see Note I )11) Oversize percent 10 1727

retained on 45 micron ISSieve, Max see Note I )

iii) Oversize percent 5 1727retained on 45 micron ISSieve, variation fromaverage percent, Max(see Notes I and 2)

w) Compressive strength at 85.0 17277 days as percent ofcontrol sample, Mirr seeNote 3)

NOTESI Any oqe of the tests specified in (i) or (ii) and (iii) indicatedmay he adopted.

7.2 A sampling device of appropriate size shall be usedto take material from the thoroughly mixed sample forpurpose of making the test specimen. At least sixrandom sub-samples shall be taken to prepare the testspecimen.

8 STORAGE AND INSPECTION8.1 The silica fume shall be stored in such a manner soas to permit easy access for proper inspection andidentification of each consignment.8.2 Adequate facilities shall be provided to the purchaserfor careful sampling and inspection, either at the sourceor at the site of work, as may be specified by thepurchaser. For guidance on storage of silica fume at site,IS 4082 maybe referred to. In general, the material shallbe stored similar to cementifly ash storage dependingupon the storage requirement in bags/bulk form.9 DELIVERYThe supply of silica fume shall be m~de in suitablequantities mutually agreed upon between the purchaserand the supplier. Where so required by the purchaser,the material shall be supplied in bags (jute laminated,multiply paper or polyethylene lines).

2 For (iii) the average shall consist of the ten preceding tests orall of the preceding tests if the number is less than ten. 10 MANUFACTURERS CERTIFICATE3 In the test method for determination of compressive strength The supplier/manufacturer shall satisfy himself that theOfsilica fume cement mortar in accordance with IS 1727, the silica fume conforms to the requirements of this\alue of factor N may be taken as one. standard and, if requested by the purchaser, shall

furnish a certificate to this effect, indicating the results6.2.1.1 Samples representing each 100 t of silica fume of the tests carried out on the samples of silica fume.shall be tested for moisture content, loss on ignitionand oversize. 11 MARKING6.2.1.2 Testing for all other physical and chemicalrequirements shall be carried out on composite samplesrepresenting not more than 400 t material each. Thecomposite samples shall be prepared by combiningportions equally from each of 100 t sample.6.2.2 The lot shall be considered passing if samplesmeet in all the requirements. The silica fume may berejected if it fails to meet any of the requirements ofthis standard. In case of dissatisfaction with the resultsof tests, the producer or supplier may request re-testingof the failed consignment.7 SAMPLE PREPARATION7.1 The grab or composite samples drawn in accordancewith 6.1 shall be mixed thoroughly. A clean and drylaboratory concrete drum mixer provides adequatemixing for the purpose. The amount of silica fume shallbe 10 to 50 percent of the volume capacity of the mixer.The mixing time shall be 5 + 1 min. A polyethylenefilm shall be secured on the drum to keep the materialin the drum during mixing of the sample lot.

11.1 Each bag/consignment of silica fume shall beclearly and permanently marked with the,

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IS 15388:200312 HEALTH AND SAFETY12.1 Owing to its fineness and its high silicon dioxidecontent, fears have been expressed over the use of thepowder forms of micro silica. A large number ofX-ray diffraction analysis suggest that it is amorphousmaterial and should therefore be less dangerous than acrystalline material. However, it is advisable to takeall necessary precautions while handling and using the

material. In many applications silica fume is handledas a aqueous slurry, redueing the dusiproblem virtuallyto zero in such cases.12.2 Similar information shall be provided in theshipping invoices accompanying the shipment of bulksilica fume.12.3 The silica fume consignment shall be in goodcondition at the time of inspection.

ANNEX ATable 2

DETERMINATION OF SPECIFIC SURFACE AREA BY GASADSORPTION USING THE BET METHOD

A-1 SCOPEThis method of test specifies the determination of thetotal specific external and internal surface area ofdisperse or porous solids by measuring the amount ofphysically adsorbed gas according to the method ofBrunauer, Emmett and Teller (BET method).The BET method cannot reliably be applied to solidswhich absorb the measuring gas.A-2 PRINCIPLEThe method specified involves the determination ofthe amount of adsorbate or adsorptive gas required tocover the external and the accessible internal poresurfaces of a solid with a complete monolayer ofadsorbate. This monolayer capacity can be calculatedfrom the adsorption isotherm using the BET equation.Nitrogen at its boiling point (about 77 K) is usuallythe most suitable adsorptive.A-3 PROCEDUREA-3.1 Sample PreparationPrior to the determination of an adsorption isotherm,remove physically adsorbed material from the samplesurface by degassing, while avoiding irreversiblechanges to the surface. As certain the maximumtemperature at which the sample is not affected byrhermogravimetric analysis or by trial experimentsusing different degassing conditions of time andtemperature. When vaccumed conditions are used,degassing to a residual pressure of approximately 1 Paor better is usually sufficient. Degassing of a samplecan also be performed at elevated temperature byflushing with helium or with adsorptive. Degassing is

complete when a steady value of the residual gaspressure p of its composition or the sample mass m isreached.A-3.2 Methods of MeasurementsAdsorption isotherms may be obtained by volumetric,gravimetric, calorimetric or spectroscopicmeasurements or by the carrier gas method usingcontinuous or discontinuous operation. The procedurerecommended by the manufacturer shall be followed.The adsorptive gas is admitted to the sample containerwhich is held at a constant temperature. The amountsadsorbed are measured in equilibrium with theadsorptive gas pressure p and plotted against relativepressure, lpo o give an adsorption isotherm.A-4 EVALUATION OF ADSORPTION DATAThe amount of gas adsorbed n~, preferably expressedin moles per gram, is plotted as ordinate against therespective pressure, plpo as abscissa to give theadsorption isotherm. The monolayer capacity n~ iscalculated using the BET equation.

PIPO _ +Cl p. [, l P/PO ] mC mc P

whereP=

Po =

n=a

3

pressure of the adsorptive in equilibriumwith the adsorbate, Pa;saturation vapour pressure of theadsorptive, Pa;specific amount adsorbed, mol g-;

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IS 15388:2003?1m = specific monolayer capacity ofadsorbate;amount of adsorbate needed to cover the

surface with a complete monolayer ofmolecules; and

C = BET parameter.A-5 TEST REPORTThe report of the determination shall include thefollowing information :

a)b)

c)

d)e)

Laboratory, type of equipment, date ofdetermination;Characterization of the sample, for examplesource, chemical composition, purity, methodof sampling, sample division;Pre-treatment and degassing conditions, forexample temperature, residual pressure,partial pressures, duration of degassing,flushing with adsorptive or helium, massreduction;Mass of degassed sample, in g;Experimental procedure for adsorptionisotherm determination, for examplevolumetric, gravimetric, chromatographic,

f-g

h)

j)k)

static or continuous gas admission, single-point determination, calibration of deadvolume or buoyancy;Adsorptive (chemical nature, purity, moisturecontent);Adsorption isotherm (n~,expressed, in mol g-l,plotted against relative pressure, p/pO), sampletemperature in kelvin, saturation vapourpressure, expressed in Pa);Evaluation parameters: multipoint or single-point determination, BET plot or range oflinearity, monolayer capacity n,expressed inmol g-], C value, molecular cross-sectionalarea am expressed in square nanometers;Specific surface area, a,, expressed in mlg;andReference material(s) used for validation ofresults.

A-6 USE OF REFERENCE MATERIALTo ensure proper working conditions and correct dataevaluation, the apparatus performance should bemonitored periodically using a certified surface areareference material.

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ANNEX B1oreword

COMMITTEE COMPOSITIONCement and Concrete Sectional Committee, CED 2

OrganizationIn personal capacity ( Chandrika at 15h Cross, 63-64, East Park Road,

Mallesu,aram, Bangalore-560003B.G. Shirke Construction Technology Limited, PuneBuilders Association of India, MumbaiBuilding Materials Technology Promotion Council, New Delhi

Cement Corporation of India Limited, New Delhi

Central Board of Irrigation and Power, New Delhi

Central Building Research Institute, Roorkee

Central Public Works Department, New Delhi

Central Road Research Institute. New Delhi

Central Soil and Materials Research Station. New Delhi

Central Water Commission, New Delhi

Directorate General of Supplies Disposals, Bangalore

Engineer-in-Chiefs Branch, Army Headquarters, New Delhi

Fly Ash Mission, Department of Science Technology, New Delhi

Gammon India Limited, Mumbai

Geological Survey of India, Jaipur

Grasim Industries Limited, Mumbai

Gujarat Ambuja Cements Limited, Ahmedabad

Hospital Services Consultancy Corporation (India) Ltd, Noida

Housing and Urban Development Corporation Limited, New Delhi

Indian Concrete institute, Mumbai

Indian Institute of Science, Bangalore[ndian Institute of Technology, RoorkceIndian Institute of Technology, KharagpurIndian Roads Congress, New Delhi

Institute for Solid Waste Research Ecological Balance,Vishakhapatnam

Representative sDR H. C. VMVESVARAYAChairmanSHRIG. R. B}{ARITKARSECRETARYSHRIT. N. G(JPTA

SHJUJ. K. PRASADAlternateSHRIMAHESHKUMAR

SHKI1. K. WAITALA/terns/eMEMBERSECRBTARY

DIRECTORCIVIL)AhernateDR C. L. VERMADR B. K. RAO Alternate

CHIEFENGINEERDESIGN)SUPERINTENDINGNGINEERS S) Alternate

HEAODIRECTORAlternate

DIRECTORSHIUP. L. KASHYAPAlternate

DIRECTORCMDD) (N W)DEPUTYDISECTOR(CMDD) (NW S) Ahernate

SHRIV. BALSUBIWMANIANSHRJR. P. SINGHAlternafe

MAJ GEN YASNMALHOTRASHIUMAHFNDRAPRASADAlternate

DR VIMALKUMARSHRIMUKf3HMATHURAlternate

SHRIS. A. RE~OISHRIM. U. SHAHAlfernafe

DR S. S. AMETADR D. K. RAI Alternate

SHRIA. K. JAJ~COL SUDHIRTAMHANEYRETD) A/terns/c

SHRJJ. P. DESAISHRIB. K. JAGETIAAlternate

SHRIJ. SARUPSHRIP. K. JAIPURIARAlternate

SHRIV. SURESHSHRIV. ARULKUMARAlternate

SHRI L. N. APTESHRID. SRINIVASANAlternate

PROFT. S. NA~ARAJPROFA. K. JAINDR ASHOKKUMARGHOSHDR S. S. SEHJLA

SHRIARUNKUMARSHARMAAlternateDR N. BHANUMATHIDAS

SHIUN. KALIDASA/ternate

Continued on page 6

5

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IS 15388:2003Colftinued ,flom page 5)

OrganizationLarsen Toubro Limited, Mumbai

Madras Cements Ltd, ChennaiMinistry of Road Transport Highways, New Delhi

National Council for Cement and Building Materials, Ballabgarh

National Test House, Kolkata

OCL India Limited, New DelhiPublic Works Department, Chennai

Research, Design Standards Organization, Lucknow

Sardar Saro\ar Narmada Nigam Limited, District Narmada

Structural Engineering Research Centre, Chemrai

The Associated Cement Companies Limited, Mumbai

The India Cements Limited, Chennai

The Indian Hume Pipe Company Limited, Mumbai

fhe Institution of Engineers (India), Bangalore

In personal capacity (F-12, Naraina Vihar, New DelhiBIS Directorate General

o

Representative sSHRI C. R. V. SUBRAMANWM

Snru S. CHOWDHtJRYA[ternOte)DR N. BHANUMATHIDASSHSUC. C. BHATTACHARYA

SHIUI. K. pANoEY A/ternateDR S. C. MAITI

DR (SHRIMATI)S. LAKMIAfternateSHRI D. K. KANUNGO

SHIUB. R. MEE~A AlternateDR S. C. AHLUWALIASUPERtNTENDINGNCINEERDESIGN)

EXECUTIVENOINEERAlternateJOINTDIRECTORSTD) (B S)/CB-11

JOINTDIRECTORSTD) (B S)/CB-I A1/ernateCHIEFENGINEERNAVGAMDAM)

SUPEIUNTENDINGNGtNEERAlternateSHRI S. GOPALAKRJSHNAN

SHJUN. P. RAIAMANEAlternateSHRIT. N. Tlwmt

DR D. GHOSHAlternateSHRIS. GOPINATH

SHRIR. ARUNACHALAMAlternate)SHRIP. R. C. NAIR

SHRIP. D. KELKARAlternateDR H. C. VtsvF.svARAYA

SHRJD. C. CHATURVEDIAlternateSHRIY. R. TANEJASHRIS . K. JAIN, Director and Head (CED)[Representing Director General Ex-oficio ]

Member SecretariesSHRI SANJAYPANT

Joint Director (CED), BISSHRIALOKKESARI

Deputy Director (CED), BIS

Cement, Pozzolana and Cement Additives Subcommittee, CED 2:1In personal capacity ( Chandrika at 15h Cross, 63-64, East Park Road,Mu{lesu,aram, Bangalore-560003

All Inciia Mini Cement Manufacturers Association, HyderabadButldlng Materials Technology Promotion Council, New DelhiCement Corporation of India Ltd, New Delhi

Cement Manufacturers Association, KolkataCentral Building Research Institute, Roorkee

Central Electricity Authority, New Delhi

Centml Public Works Department, New Delhi

DR H. C. VISVESVARAYAConvenerSHRIK. GOPI PRASAOSHRIJ. K. PRASADSHRIL K. WATTAL

SHRIMATISARASWATHIEW AlternateSHRI SOMNATHBANERIEEDR B. K. RAO

DR MANJITSINOHAlternateSHRI Y. K. SHARMA

SHRJMOHANKUMARAlternateCHIEFENGINEERCDO)

SUPERINTENDINGNGINEERS S) Alternate

Contittued on page 7

6

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IS 15388:2003

OrganizatiOtlCentral Road Research Institute, New Delhi

Central Soil and Materials Research Station, New Delhi

Central Water Commission, New Delhi

Dalmia Cement (Bharat) Limited, New Delhi

Engineer-in-Chiefs Branch, Chandigarh

Fly Ash Mission. Department of Science Technology, New Delhi

Gammon India Limited, MurnbaiCimsim Industries Limited, Mumbai

Gu~arat Ambuja Cements Ltd, Ahmedabad

Gujaral Engineering Research Institute, Vadodara

lndlan Concrete Institute, Chennai

Indian Institute of Science, BangaloreIndian Instnute of Technology, KharagpurIodorama Cement Limited, Mumbai

Larsen Toubro Limited, MumbaiMadras Cements Ltd, ChennaikMaharashtra Engineering Research Institute, Nasik

Ministry of Commerce Industry, New Delhi

Ministry of Road Transport Highways, New Delhi

National Council of Cement and Building Materials, Ballabgarh

National Test House (WR), Mumbai

Orissa Cement Limited, New DelhiPublic Works Department, Chennai

Research, Design and Standards Organization, Lucknow

Tamtl Nadu Minerals Limited, ChennaiThe Associated Cement Company Ltd, Mumbai

Tbe Hindustan Construction Company Limited, Mumbai

Representative sSHRI S. S. SE~HRA

SHRI SATANDERKUMARAlternateDIRECTOR

Stou N. CHANDRASBKARANAlternateDIRITTOR(C MDD-11)

DEPUTYDKWCTORCMDD-H) Al[erna/cDR K. C. NARANG

SHRIC. S. SHARMAAlternateStirumA LAL

LT-COL DWJENORAKUMARAlternateDR VIMALKUMAR

SHRIMUKWHMATHURAlternateSHRIS . A. RLDDISHRIA. K. JAIN

COL SUDHIRTAMHANEYRETD) Alferwak,RI J. P. DESAISHRIB. K. JACiETIAAlferna[e

DIRFCTORSHRIJ. K. PAT~LA/fernafe

DR C. S. VISWANATHAPROFM. S. SHETTYAlternate

PROFT. S. NAGARAJDR ASHOKKUMARGHOSHSHRIK. K. TAPAJUA

SHP.JA. K. PRASHARAlternateSHRIS. CHOWDHURYDR N. BHANUMATHIDASDIRECTOR

RESEARCHOFFICERAlternafeSHRIP . K. JAIN

SHFUSHAISHKUMARAlternateSHSUV. VELAYUTHAM

SHRI1. K. PANDEYAlternateDR K. MOHAN

DR (SHRIMATI)S. LAXMIAlternateSHRIB. R, MEENA

SHRIB. K. MANDALAlternateDR S. C. AHLUWALIASUPERINTENDINGNGINEERDESIGN)

SENIORDFPUTYCHIEFENGINEERAlterna/eDEPUTYDIRECTOR(B F)

ASSISTANTDESIGNENGINEERB F) AkowafeSHRIK. SUMA~THBABUSHRIT. N. TIWARI

DR D. GHOSHAlternateSHRI A. P. PHADKE

SHRID. M. SAVURA[fernafe

. a

7

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Bureau of Indian Standards131S is a statutory institution established under the Bureau of Zndian Standards Act, 1986 to promoteharmonious development of the activities of standardization, marking and quality certification of goodsand attending to connected matters in the country.CopyrightBIS has the copyright of all its publications. No part of these publications may be reproduced in any formwithout the prior permission in writing of BIS. This does not preclude the free use, in the course ofimplementing the standard, of necessary details, such as symbols and sizes, type or grade designations.Enquiries relating to copyright be addressed to the Director (Publications), BIS.Review of Indian StandardsAmendments are issued to standards as the need arises on the basis of comments. Standards are also reviewedperiodically; a standard along with amendments is reaffirmed when such review indicates that no changes areneeded; if the review indicates that changes are needed, it is taken up for revision. Users of Indian Standardsshould ascertain that they are in possession of the latest amendments or edition by referring to the latest issue ofBIS Catalogue and Standards: Monthly Additions.This Indian Standard has been developed from DOC : No. CED 2 (4956).

Amendments Issued Since Publication

Amend No. Date of Issue Text Affected

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