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1、BRITISH STANDARD BS 146:1996 Specification for Portland blastfurnace cements Licensed Copy: sheffieldun sheffieldun, na, Fri Nov 24 08:28:45 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 146:1996 This British Standard, having been prepared under the direction of the Sector Board for Building and Civ
2、il Engineering, was published under the authority of the Standards Board and comes into effect on 15 June 1996 BSI 01-1999 First published May 1923 Second edition July 1926 Third edition June 1932 Fourth edition September 1941 Fifth edition November 1947 Sixth edition March 1958 Seventh edition Octo
3、ber 1973 Eighth edition November 1991 Ninth edition June 1996 The following BSI references relate to the work on this standard: Committee reference B/516/6 Draft for comment 94/100796 DC ISBN 0 580 25330 9 Committees responsible for this British Standard The preparation of this British Standard was
4、entrusted by Technical Committee B/516, Cement and lime, to Subcommittee B/516/6, Cement specifications, upon which the following bodies were represented: British Aggregate Construction Materials Industries British Cement Association British Precast Concrete Federation British Ready Mixed Concrete A
5、ssociation Cement Admixtures Association Cementitious Slag Makers Association County Surveyors Society Department of the Environment (Building Research Establishment) Department of Transport (Highways Agency) Electricity Association National Rivers Authority Quality Ash Association Society of Chemic
6、al Industry Amendments issued since publication Amd. No.DateComments Licensed Copy: sheffieldun sheffieldun, na, Fri Nov 24 08:28:45 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 146:1996 BSI 01-1999i Contents Page Committees responsibleInside front cover Forewordii 1Scope1 2References1 3Definitions
7、1 4Cement1 5Constituents1 6Composition, notation and manufacture2 7Compressive strength3 8Physical properties3 9Chemical properties3 10Marking3 11Information to be provided3 12Sampling and testing for acceptance inspection at delivery4 Annex A (informative) Conformity criteria (cement manufacturers
8、autocontrol)6 Annex B (informative) Compositional requirements for all cement types10 Annex C (informative) Product guidance11 Table 1 Composition2 Table 2 Compressive strength3 Table 3 Chemical properties4 Table 4 Acceptance inspection limits5 Table A.1 Minimum testing frequencies7 Table A.2 Parame
9、ters determining the conformity procedure8 Table A.3 Major defects9 Table A.4 Acceptability constant kA9 Table A.5 Acceptable number of defects cA9 Table B.1 Extreme compositional possibilites10 List of referencesInside back cover Licensed Copy: sheffieldun sheffieldun, na, Fri Nov 24 08:28:45 GMT+0
10、0:00 2006, Uncontrolled Copy, (c) BSI BS 146:1996 ii BSI 01-1999 Foreword This edition of this British Standard has been prepared by Subcommittee B/516/6. It introduces technical changes but it does not reflect a full revision of the standard, which will be undertaken in due course. It is based on t
11、he work of Technical Committee 51, Cement and building limes, of the European Committee for Standardization (CEN), which has prepared a European Prestandard specification for cements published as DD ENV 197-1. As an intrinsic part of this activity, CEN has published EN 196, a series of methods of te
12、sting cement, which the UK is implementing to replace the relevant Parts of BS 4550. In consequence, this British Standard specifies requirements in terms of the test procedures in BS EN 196. It supersedes BS 146:1991 which is withdrawn. The requirements for compressive strength, physical and chemic
13、al properties are specified as characteristic values and conformity is assessed by means of a statistical procedure for continuous inspection operated by the cement manufacturer (autocontrol) (see annex A). This includes the concept of “major defects” which are “likely to reduce materially the usabi
14、lity of the cement for its intended purpose”. However, DD ENV 197-1 is considered to be inappropriate in its entirety for the manufacture of cement in the UK and the annex therefore incorporates several footnotes identifying specific aspects. In particular, it is assumed, for this edition of this Br
15、itish Standard, that some limits are required for acceptance inspection. Clause 12 therefore gives appropriate values which in several cases are more stringent than those for major defects given in annex A. The strength requirements are based on the BS EN 196-1 mortar prism test at 28 days. In addit
16、ion to the two classes of standard strength, 32.5 and 42.5, with two and three subclasses respectively of early strength, this British Standard includes a higher class of standard strength, 52.5 with two subclasses of early strength, to cover all Portland blastfurnace cements available in the UK (se
17、e Table 2). It should be noted that for prescribed or standard mixes, as described in BS 5328-1, unless the cement content is increased appropriately, the use of cements of the 32.5 standard strength class will lead to concrete of lower compressive strength and may reduce durability, compared with c
18、ements of a higher strength class. This edition introduces the following changes. a) The two methods of producing Portland blastfurnace cements, i.e. by intergrinding and by dry blending, have been retained (see 6.3). A procedure for combining Portland cement and ground granulated blastfurnace slag
19、in the concrete mixer is included in BS 5328-1. b) Compositional requirements are expressed as a percentage of the total mass of the constituents but excluding calcium sulfate and any additives. This departure from the traditional method of calculation in the UK is fully explained in annex B. c) Req
20、uirements are not specified for fineness, but the limit in BS 6699 is applicable to the blastfurnace slag constituent where the dry blending method is used (see 6.3). d) Guidance on the use of cement has been included in annex C and attention is drawn to the safety precautions recommended therein wh
21、en working with cement. Cement will partially hydrate when exposed to water vapour; annex C also includes guidance on storage. New editions of other British Standards for cement, i.e. BS 12, BS 4027, BS 4246, BS 6588, BS 6610 and BS 7583 have been revised at the same time. Product certification. Pur
22、chasers are recommended to specify cement manufactured and supplied to a nationally recognized third party product certification scheme. Licensed Copy: sheffieldun sheffieldun, na, Fri Nov 24 08:28:45 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 146:1996 BSI 01-1999iii A British Standard does not p
23、urport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside fron
24、t cover, pages i to iv, pages 1 to 12, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover. Licensed Copy: sheffieldun sheffieldun, na, Fri Nov 24
25、08:28:45 GMT+00:00 2006, Uncontrolled Copy, (c) BSI iv blank Licensed Copy: sheffieldun sheffieldun, na, Fri Nov 24 08:28:45 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 146:1996 BSI 01-19991 1 Scope This British Standard1) specifies requirements for the composition and manufacture and for the stre
26、ngth, physical and chemical properties of two Portland blastfurnace cements, Portland slag cement and blastfurnace cement, as characteristic values. Requirements for marking, provision of information, sampling and testing for acceptance at delivery are also specified. It gives the procedures for the
27、 manufacturers autocontrol system to ensure conformity. 2 References 2.1 Normative references This British Standard incorporates, by reference, provisions from specific editions of other publications. These normative references are cited at the appropriate points in the text and the publications are
28、 listed on the inside back cover. Subsequent amendments to, or revisions of, any of these publications apply to this British Standard only when incorporated in it by updating or revision. 2.2 Informative references This British Standard refers to other publications that provide information or guidan
29、ce. Editions of these publications current at the time of issue of this standard are listed on the inside back cover, but reference should be made to the latest editions. 3 Definitions For the purposes of this British Standard the definitions in BS 6100-6.1 apply together with the following. 3.1 cha
30、racteristic value that value of a property corresponding to an acceptable percentage of defects, generally 10 % but 5 % for the lower strength limits 4 Cement NOTE 1Cement is a hydraulic binder, i.e. it is a finely ground inorganic material which, when mixed with water, forms a paste which sets and
31、hardens by means of hydration reactions and processes and which, after hardening, retains its strength and stability even under water. Cement conforming to this British Standard shall, when appropriately batched and mixed with aggregate and water, be capable of producing mortar or concrete which ret
32、ains workability for a sufficient time and shall after defined periods attain specified strength levels and also possess long-term volume stability. NOTE 2Hydraulic hardening of cement conforming to this British Standard is primarily due to the hydration of calcium silicates2), but other chemical co
33、mpounds may also participate in the hardening process, e.g. aluminates. The sum of the proportions of reactive calcium oxide (CaO)3) and reactive silicon dioxide (SiO2)4) shall be not less than 50 % (m/m). Cement conforming to this British Standard ultimately consists of individual small grains of d
34、ifferent materials but it shall be statistically homogeneous in composition. A high degree of uniformity in all cement properties shall be obtained through continuous mass production processes, in particular adequate grinding and homogenization processes. NOTE 3Qualified and skilled personnel and fa
35、cilities to test, evaluate and adjust product quality are essential for producing cement conforming to this British Standard. During the cement manufacturing process and its control, the composition of the cement shall be kept within the limits specified in this British Standard. 5 Constituents 5.1
36、Portland cement clinker Portland cement clinker is a hydraulic material which shall consist of not less than two-thirds by mass of calcium silicates (CaO)3.SiO2 and (CaO)2.SiO2), the remainder containing aluminium oxide (Al2O3), iron oxide (Fe2O3) and other oxides. The ratio by mass (CaO)/(SiO2) sha
37、ll be not less than 2.0. The content of magnesium oxide (MgO) shall not exceed 5.0 % (m/m). 1) Other types of cement standardized in the UK are specified in BS 12, BS 915, BS 1370, BS 4027, BS 4246, BS 4248, BS 6588, BS 6610 and BS 7583. 2) There are also cements whose hardening is mainly due to oth
38、er compounds, e.g. calcium aluminate in high alumina cement. 3) Reactive calcium oxide (CaO) is considered to be only that fraction of the CaO which under normal hardening conditions can form calcium silicate hydrates or calcium aluminate hydrates. To evaluate this fraction, the total CaO content is
39、 to be reduced by the part calculated as calcium carbonate (CaCO3) on the basis of the measured carbon dioxide (CO2) content and the part calculated as calcium sulfate (CaSO4) on the basis of the measured sulfate content (expressed as SO3) disregarding the SO3 taken up by alkalis. 4) Reactive silico
40、n dioxide (SiO2) is defined as that fraction of the SiO2 which, after treatment with hydrochloric acid (HCl), is soluble in boiling potassium hydroxide (KOH) solution. The quantity of reactive SiO2 is determined by subtracting from the total SiO2 content (see 13.9 of BS EN 196-2:1995) that fraction
41、of the SiO2 contained in the insoluble residue (see clause 10 of BS EN 196-2:1995), both on a dry basis. Licensed Copy: sheffieldun sheffieldun, na, Fri Nov 24 08:28:45 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 146:1996 2 BSI 01-1999 Portland cement clinker shall be made by burning, at least to
42、sintering, a precisely specified mixture of raw materials (raw meal, paste or slurry) containing CaO, SiO2, Al2O3 and small quantities of other materials. The raw meal, paste or slurry shall be finely divided, intimately mixed and therefore homogeneous. 5.2 Granulated blastfurnace slag NOTE 1Granula
43、ted blastfurnace slag is a latent hydraulic material, i.e. it possesses hydraulic properties when suitably activated. Granulated blastfurnace slag shall contain at least two-thirds by mass of glassy slag. The slag shall consist of at least two-thirds by mass of the sum of CaO, MgO and SiO2. The rema
44、inder contains Al2O3 together with small amounts of other oxides. The ratio by mass (CaO + MgO)/(SiO2) shall exceed 1.0 (see also 6.3). NOTE 2Granulated blastfurnace slag is made by rapid cooling of a slag melt of suitable composition, as obtained in smelting iron ore in a blastfurnace. 5.3 Minor ad
45、ditional constituents Minor additional constituents if present shall be one or more of natural pozzolana, pulverized-fuel ash (fly ash) or filler. NOTE 1The minor additional constituents should not promote corrosion of the reinforcement or impair the properties of the cement or of the mortar or conc
46、rete made from the cement. NOTE 2Natural pozzolanas are usually substances of volcanic origin or sedimentary rocks with appropriate chemical and mineralogical composition. Fly ash is obtained by electrostatic or mechanical precipitation of dust-like particles from the flue gases from furnaces fired
47、with pulverized hard coal. Ash obtained by other methods is not considered in this British Standard. For the purposes of this British Standard, the term “filler” covers any natural or artificial inorganic mineral materials other than blastfurnace slag, natural pozzolana or pulverized-fuel ash, e.g.
48、calcareous materials, which, after appropriate preparation, due to their particle size distribution, improve the physical properties of the cement (such as workability or concrete bleeding). 5.4 Calcium sulfate Calcium sulfate shall be added in small quantities to the other constituents of cement du
49、ring its manufacture in order to control setting. NOTECalcium sulfate can be gypsum (calcium sulfate dihydrate, CaSO4.2H2O), hemihydrate (partially dehydrated gypsum, CaSO4.H2O), or anhydrite (anhydrous calcium sulfate, CaSO4) or any mixture of them. Gypsum and anhydrite are found naturally. Calcium sulfate is also available as a by-product of certain industrial processes. 5.5 Additives If the total quantity of additives exceeds 1.0 % (m/m) of the cement, the type and quantity shall be stated on the packaging and/or on the delivery note. NOTE 1These additiv
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