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1、| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | BRITISH STANDARD BS EN 480-11:1999 The Eur
2、opean Standard EN 480-11:1998 has the status of a British Standard ICS 91.100.30 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW Admixtures for concrete, mortar and grout Test methods Part 11: Determination of air void characteristics in hardened concrete Licensed Copy: sheffi
3、eldun sheffieldun, na, Sat Nov 04 09:27:46 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS EN 480-11:1999 This British Standard, having been prepared under the direction of the Sector Committee for Building and Civil Engineering, was published under the authority of the Standards Committee and comes i
4、nto effect on 15 February 1999 BSI 02-1999 ISBN 0 580 30794 8 Amendments issued since publication Amd. No.DateText affected National foreword This part of BS EN 480 has been prepared by Subcommittee B/517/3 and is the English language version of EN 480-11:1998, Admixtures for concrete, mortar and gr
5、out Test methods Part 11: Determination of air void characteristics in hardened concrete, published by the European Committee for Standardization (CEN). A list of organizations represented on this subcommittee can be obtained on request to its secretary. This standard is part of a package of standar
6、ds comprising BS EN 480 Parts 1, 2, 4, 5, 6, 8, 10, 11 and 12, and BS EN 934 Parts 2 and 6. When all the standards in this package have been published, BS 5075 Parts 1, 2 and 3 will be amended by deleting all the clauses that conflict with the package. This standard has been prepared to provide a me
7、thod to test air entraining admixtures for concrete for conformity to BS EN 943-2. It may find wider use to provide data on the air void spacing in air entrained concrete. The method is not used for testing air entraining/plasticizing admixtures for mortar covered by prEN 934-3. The UK has drawn the
8、 attention of CEN to some errors that have been corrected in this English language version. Cross-references The British Standards which implement international or European publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled International
9、Standards Correspondence Index, or by using the Find facility of the BSI Standards Electronic Catalogue. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Stan
10、dard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, the EN title page, pages 2 to 12, an inside back cover and a back cover. Licensed Copy: sheffieldun sheffieldun, na, Sat Nov 04 09:27:46 GMT+00:00 2006, Unco
11、ntrolled Copy, (c) BSI CEN European Committee for Standardization Comite Europe en de Normalisation Europa isches Komitee fu r Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels 1998 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members
12、. Ref. No. EN 480-11:1998 E EUROPEAN STANDARDEN 480-11 NORME EUROPE ENNE EUROPA ISCHE NORM October 1998 ICS 91.100.10; 91.100.30 Descriptors: construction materials, concrete, hardened concrete, mortars: material, grouting, concrete admixtures, tests, characteristics, void fractions, air English ver
13、sion Admixtures for concrete, mortar and grout Test methods Part 11: Determination of air void characteristics in hardened concrete Adjuvants pour be tons, mortiers et coulis Me thodes dessais Partie 11: De termination des caracte ristiques des vides dair dans le be ton durci Zusatzmittel fu r Beton
14、, Mo rtel und Einpremo rtel Pru fverfahren Teil 11: Bestimmung von Luftporenkennwerten in Festbeton This European Standard was approved by CEN on 16 October 1997. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standar
15、d the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CEN member. This European Standard exists in three official versions (English, French, Ge
16、rman). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark,
17、Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. Licensed Copy: sheffieldun sheffieldun, na, Sat Nov 04 09:27:46 GMT+00:00 2006, Uncontrolled Copy, (c) BSI Page 2 EN 480-11:1998 BSI 02-1999 Foreword T
18、his European Standard has been prepared by Technical Committee CEN/TC 104, Concrete (performance, production, placing and compliance criteria), the Secretariat of which is held by DIN. This European Standard shall be given the status of a national standard, either by publication of an identical text
19、 or by endorsement, at the latest by April 1999, and conflicting national standards shall be withdrawn at the latest by April 1999. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austri
20、a, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom. Contents Page Foreword2 1Scope3 2Normative references3 3Definitions3 3.1Air void3 3.2Total air content A3 3.3P
21、aste Content P3 3.4Specific surface of air void system a3 3.5Spacing factor L3 3.6Air void distribution3 3.7Micro air content A3003 3.8Traverse line3 3.9Length of traverse Ttot4 3.10Chord length l4 3.11Chord length classification4 4Principle4 5Equipment4 5.1General4 5.2Specimen preparation4 5.3Micro
22、scopical analysis4 6Specimen production and preparation5 6.1Specimen production5 6.2Preparation of test surface5 Page 7Microscopical procedure6 7.1Basic procedure6 7.2Values recorded6 8Calculations7 8.1Data obtained7 8.2Total traverse length7 8.3Total air content7 8.4Total number of chords measured7
23、 8.5Specific surface of the air7 8.6Paste: air ratio7 8.7Spacing factor7 8.8Micro-air content7 8.9Air void distribution7 8.9.1 Basis of calculation7 8.9.2 Calculation of chord frequency7 8.9.3 Calculation of void frequency8 8.9.4 Calculation of void distribution8 8.9.5 Calculation of air content8 8.
24、9.6 Presentation of results8 8.9.7 Column contents8 9Test report8 Annex A (informative) Theoretical basis of calculations involved in Table 110 Annex B (informative) Worked example of the calculation of air void distribution11 Licensed Copy: sheffieldun sheffieldun, na, Sat Nov 04 09:27:46 GMT+00:00
25、 2006, Uncontrolled Copy, (c) BSI Page 3 EN 480-11:1998 BSI 02-1999 1 Scope This European Standard describes a test method for determination of the air void structure in a hardened concrete sample which contains entrained air. The air void structure is described by means of the following parameters,
26、 which are defined in clause 3: i) total air content; ii) specific surface of air void system; iii) spacing factor; iv) air void size distribution; v) micro air content. The method as described is only suitable for use on hardened concrete specimens where the original mix proportions of the concrete
27、 are accurately known and the specimen is representative of these mix proportions. This will generally be the case only where the concrete concerned is produced in a laboratory. 2 Normative references This European Standard incorporates by dated or undated reference, provisions from other publicatio
28、ns. These normative references are cited at the appropriate places in the text and the publications are listed hereafter. For dated references, subsequent amendments to or revisions of any of these publications apply to this European Standard only when incorporated in it by amendment or revision. Fo
29、r undated references the latest edition of the publication referred to applies. EN 480-1, Admixtures for concrete, mortar and grout Test methods Part 1: Reference concrete and reference mortar for testing. EN 934-2, Admixtures for concrete, mortar and grout Concrete admixtures Part 2: Definitions an
30、d requirements. ISO 2736-2, Concrete tests Making of test specimens Part 2: Making and curing of test specimens for strength tests. 3 Definitions For the purposes of this standard, the following definitions apply. 3.1 air void space enclosed by the cement paste that was filled with air or other gas
31、prior to the setting of the paste. This does not refer to voids of submicroscopic dimensions, such as the porosity inherent in a hydrated cement paste. For the purposes of this test method, all voids within the cement paste are considered that are visible at the test magnification with an intercepte
32、d chord length of up to 4 mm, other than obvious cracks 3.2 total air content A proportion of the total volume of the concrete that is air voids; expressed as a percentage by volume 3.3 paste content P proportion of the total volume of the concrete that is hardened cement paste, expressed as a perce
33、ntage by volume. This is the sum of the proportional volumes of cement, mixing water and any admixtures present. For the purposes of this test method it is calculated from the batch weights of the test concrete 3.4 specific surface of air void system a calculated parameter representing the total sur
34、face area of the air voids divided by their volume; units are mm21. The calculation method used is based on the average chord length and is valid for any system of spherical voids 3.5 spacing factor L calculated parameter related to the maximum distance of any point in the cement paste from the peri
35、phery of an air void, measured through the cement paste; units are mm. The calculation of this parameter assumes that all air voids present are of uniform size and are evenly distributed through the cement paste such that the model system has the same total volume and surface area as the real system
36、 NOTEThis model is an approximation; the value obtained is probably larger than the actual value. 3.6 air void distribution set of calculated values of the number and/or volume of air voids of various diameters within the hardened cement paste NOTEThe model used for this calculation assumes that onl
37、y voids having diameters of certain discrete values are present. This model will therefore lie between the real case and the single diameter model that is used in the calculation of the spacing factor. A graphical representation of the distribution can be obtained by plotting the volume of air attri
38、butable to each size of void, either as a volume percentage of the cement paste or as a proportion of the total air content. 3.7 micro air content A300 calculated parameter representing the air content attributed to air voids of 0,3 mm (300 mm) diameter or less; the value for this parameter is obtai
39、ned during the calculation of the air void distribution 3.8 traverse line one of a series of lines across the polished specimen face traced by the relative motion of the microscope and specimen during the test Licensed Copy: sheffieldun sheffieldun, na, Sat Nov 04 09:27:46 GMT+00:00 2006, Uncontroll
40、ed Copy, (c) BSI Page 4 EN 480-11:1998 BSI 02-1999 3.9 length of traverse Ttot total distance traversed across the surface of the specimens during the test measurement. It is made up of two parts, the total traverse across the surface on solid phases, Ts, and across air voids, Ta, in each case the u
41、nits are mm 3.10 chord length l distance along the traverse line across an air void, units are mm 3.11 chord length classification chord lengths across individual air voids are classified into classes based on the length of the chord. The total number of chords in any particular class, i, is designa
42、ted by Ci. Clause 8.9 and Table 1 contain details of the boundary values for the classes 4 Principle Hardened samples of air-entrained concrete are sectioned perpendicular to the original free upper surface to produce specimens for analysis. These specimens are then ground and polished to produce a
43、smooth flat surface finish suitable for microscopical investigation. The air void structure is examined by scanning along a series of traverse lines running parallel to the original free upper surface. The number of air voids intersected by the traverse lines are recorded, as are the individual chor
44、d lengths of the traverse across the air voids. A mathematical analysis of the recorded data then allows a description of the air void system in terms of the required parameters. Other methods of air void analysis such as the point count method may be used provided that they can be shown to give ess
45、entially the same results for the air void parameters required as the method described herein. In the case of dispute the method described in this standard shall be used. 5 Equipment 5.1 General The following list of equipment has been found suitable for this test. Other apparatus may be used if it
46、can be shown to produce satisfactory results. Not all the equipment may be required for individual test measurements. 5.2 Specimen preparation a) Diamond saw. b) Grinding machine. One or more instruments able to provide a finished surface of the required quality. These include instruments with a cas
47、t iron disc, usually with a minimum diameter of 400 mm, used in conjunction with silicon carbide powder of various grain sizes (typically 120, 60, 30, 16 and 12 mm) or instruments with special grinding discs of the varying grain sizes. c) Refrigerator and oven. d) Various chemicals for treatment of
48、the polished surface, including; glycerol, stamp ink (matt or dull black, not water soluble), zinc paste and gypsum powder (grain size # 3 mm). 5.3 Microscopical analysis a) A motorized or hand operated cross-traverse table. This consists of a platform, on which the specimen rests, which is mounted
49、on lead screws by means of which it can be moved smoothly in two perpendicular directions. One lead screw is required for movement in a direction perpendicular to and two lead screws for movement parallel to the original upper surface. The lead screws should be capable of providing a measure of the total distance travelled to an accuracy of 1 %. b) Lighting equipment. c) A means of recording the traverse distances and the total number of air voids traversed, divided into classes based on the individual chord lengths. d) Stereoscopi