1、 g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58Test methods Part 11: Determination of air void characteristics in hardened concreteThe European St
2、andard EN 480-11:2005 has the status of a British StandardICS 91.100.30Admixtures for concrete, mortar and grout BRITISH STANDARDBS EN 480-11:2005BS EN 480-11:2005This British Standard was published under the authority of the Standards Policy and Strategy Committee on 14 December 2005 BSI 14 Decembe
3、r 2005ISBN 0 580 47268 Xrequest to its secretary.Cross-referencesThe British Standards which implement international or European publications referred to in this document may be found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Sea
4、rch” facility of the BSI Electronic Catalogue or of British Standards Online.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application.Compliance with a British Standard does not of itself confer immunity from legal obl
5、igations.Summary of pagesThis document comprises a front cover, an inside front cover, the EN title page, pages 2 to 19 and a back cover.The BSI copyright notice displayed in this document indicates when the document was last issued.Amendments issued since publicationAmd. No. Date CommentsA list of
6、organizations represented on this subcommittee can be obtained on present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep UK interests informed; monitor related international and European developments and promulgate them in t
7、he UK.National forewordThis British Standard is the official English language version of EN 480-11:2005. It supersedes BS EN 480-11:1999 which is withdrawn.The UK participation in its preparation was entrusted by Technical Committee B/517, Concrete, to Subcommittee B/517/3, Admixtures, which has the
8、 responsibility to: aid enquirers to understand the text;EUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN 480-11September 2005ICS 91.100.30 Supersedes EN 480-11:1998 English VersionAdmixtures for concrete, mortar and grout - Test methods - Part11: Determination of air void characteristics in harden
9、edconcreteAdjuvants pour btons, mortiers et coulis - Mthodesdessai -Partie 11: Dtermination des caractristiques desvides dair dans le bton durciZusatzmittel fr Beton, Mrtel und Einpressmrtel -Prfverfahren - Teil 11: Bestimmung vonLuftporenkennwerten in FestbetonThis European Standard was approved by
10、 CEN on 28 July 2005.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards m
11、ay be obtained on application to the Central Secretariat or to any CEN member.This European Standard exists in three official versions (English, French, German). A version in any other language made by translationunder the responsibility of a CEN member into its own language and notified to the Cent
12、ral Secretariat has the same status as the officialversions.CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Polan
13、d, Portugal, Slovakia,Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement Centre: rue de Stassart, 36 B-1050 Brussels 2005 CEN All rights of exploitation in any form and by any means rese
14、rvedworldwide for CEN national Members.Ref. No. EN 480-11:2005: EEN 480-11:2005 (E) 2 Contents Page Foreword 3 1 Scope .4 2 Normative references .4 3 Terms and definitions.4 4 Principle.5 5 Equipment .6 5.1 General 6 5.2 Specimen preparation 6 5.3 Microscopical analysis .6 6 Specimen production and
15、preparation7 6.1 Specimen production .7 6.2 Preparation of test surface.7 7 Microscopic procedure.8 7.1 Basic procedure8 7.2 Values recorded 9 8 Calculations.10 8.1 Data obtained 10 8.2 Total traverse length.10 8.3 Total air content 10 8.4 Total number of chords measured 10 8.5 Specific surface of t
16、he air.11 8.6 Paste: air ratio.11 8.7 Spacing factor .11 8.8 Micro-air content.11 8.9 Air void distribution11 9 Test report .13 Annex A (informative) Theoretical basis of calculation involved in Table 1 15 Annex B (informative) Worked example of the calculation of air void distribution.18 EN 480-11:
17、2005 (E) 3 Foreword This European Standard (EN 480-11:2005) has been prepared by Technical Committee CEN/TC 104 “Concrete and related products”, 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 tex
18、t or by endorsement, at the latest by March 2006, and conflicting national standards shall be withdrawn at the latest by March 2006. This document is part of the series EN 480 “Admixtures for concrete, mortar and grout Test methods“ which comprises the following Part 1 Reference concrete and referen
19、ce mortar for testing Part 2 Determination of setting time Part 4 Determination of bleeding of concrete Part 5 Determination of capillary absorption Part 6 Infrared analysis Part 8 Determination of the conventional dry material content Part 10 Determination of water soluble chloride content Part 11
20、Determination of air void characteristics in hardened concrete Part 12 Determination of the alkali content of admixtures Part 13 Reference masonry mortar for testing mortar admixtures Part 14 Admixtures for concrete, mortar and grout - Test methods - Part 14: Measurement of corrosion susceptibility
21、of reinforcing steel in concrete - Potentiostatic electro-chemical test method 1)This document is applicable together with the other standards of the EN 480 series. This document supersedes EN 480-11:1998. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the
22、 following countries are bound to implement this European Standard: Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain,
23、Sweden, Switzerland and United Kingdom. 1) This part is under preparation EN 480-11:2005 (E) 4 1 Scope This document 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 fol
24、lowing parameters, 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
25、 the concrete 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 The following referenced documents are indispensable for the application of this docum
26、ent. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 480-1, Admixtures for concrete, mortar and grout Test methods Part 1: Reference concrete and reference mortar for testing; EN 934-2,
27、 Admixtures for concrete, mortar and grout Part 2: Concrete admixtures Definitions, requirements, conformity, marking and labelling ISO 1920-3, Testing of concrete - Part 3: Making and curing test specimens 3 Terms and definitions For the purposes of this European Standard, the following terms and d
28、efinitions apply. 3.1 air void space enclosed by the cement paste that was filled with air or other gas 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 vo
29、ids within the cement paste are considered that are visible at the test magnification with an intercepted 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 cont
30、ent P proportion of the total volume of the concrete that is hardened cement paste, expressed as a percentage 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
31、 test concrete. EN 480-11:2005 (E) 5 3.4 specific surface of air void system calculated parameter representing the total surface area of the air voids divided by their volume; units are mm-1. The calculation method used is based on the average chord length and is valid for any system of spherical vo
32、ids 3.5 spacing factor calculated parameter related to the maximum distance of any point in the cement paste from the periphery 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 dis
33、tributed through the cement paste such that the model system has the same total volume and surface area as the real system NOTE This 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
34、of air voids of various diameters within the hardened cement paste NOTE The model used for this calculation assumes that only 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 calculati
35、on of the spacing factor. A graphical representation of the distribution can be obtained by plotting the volume of air attributable 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 rep
36、resenting the air content attributed to air voids of 0,3 mm (300 m) diameter or less. The value for this parameter is obtained 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 microsc
37、ope and specimen during the test 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 units are mm 3.10 c
38、hord length l distance along the traverse line across an air void, units are m 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 designated by Ci. in8.9 an
39、d 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 smooth flat surface fini
40、sh suitable for microscopic investigation. EN 480-11:2005 (E) 6 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 chord len
41、gths 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 essentia
42、lly the same results for the air void parameters required as the method described herein. In the case of dispute the method described in this document 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 can b
43、e 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 cast iro
44、n 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 m) or instruments with special grinding discs of the varying grain sizes; c) Refrigerator and oven; d) Various chemicals for treatment of the po
45、lished surface, including; glycerol, stamp ink (matt or dull black, not water soluble), zinc paste and gypsum powder (grain size 3 m). 5.3 Microscopical analysis a) A motorised or hand operated cross traverse table. This consists of a platform, on which the specimen rests, which is mounted on lead s
46、crews 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 dis
47、tance 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) Stereoscopic microscope, magnification (100 10) x. The instrument used must be capa
48、ble of providing the necessary resolution to classify the chords measured into classes as detailed in section 7.2. Other forms of imaging may be used, such as a television camera mounted on the microscope with linked monitor. In these cases the image used for measurements shall be selected so as to
49、produce results for voids counted which are consistent with those produced using direct visual examination through a microscope. NOTE Use of imaging systems of other magnification may lead to differences in the diameter of the smallest visible voids. These may lead to counting variations and different values for calculated parameters. EN 480-11:2005 (E) 7 6 Specimen production and preparation 6.1 Specimen production Two samples, of minimum dimension 150 mm, shall be cast from the concrete under investigation
