1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS EN 772-21:2011Methods of test for masonryunitsPart 21: Determination of water absorptionof clay and calcium silicate masonry units bycold water absorptionBS EN 772-21:2011 BRI
2、TISH STANDARDNational forewordThis British Standard is the UK implementation of EN 772-21:2011.The UK participation in its preparation was entrusted to TechnicalCommittee B/519/1, Masonry units.A list of organizations represented on this committee can beobtained on request to its secretary.This publ
3、ication does not purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. BSI 2011ISBN 978 0 580 70261 7ICS 91.100.15Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the au
4、thority of theStandards Policy and Strategy Committee on 31 May 2011.Amendments issued since publicationDate Text affectedBS EN 772-21:2011EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 772-21 May 2011 ICS 91.100.15 English Version Methods of test for masonry units - Part 21: Determination of
5、water absorption of clay and calcium silicate masonry units by cold water absorption Mthodes dessai des lments de maonnerie - Partie 21: Dtermination de labsorption deau des lments de maonnerie en terre cuite et en silico-calcaire par absorption deau froide Prfverfahren fr Mauersteine - Teil 21: Bes
6、timmung der Kaltwasseraufnahme von Mauerziegeln und Kalksandsteinen This European Standard was approved by CEN on 25 December 2010. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national stan
7、dard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in a
8、ny other language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Rep
9、ublic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN D
10、E NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2011 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 772-21:2011: EBS EN 772-21:2011EN 772-21:2011 (E) 2 Contents Page Foreword 31
11、Scope 42 Normative references 43 Principle 44 Symbols 45 Apparatus .46 Preparation .56.1 Sampling .56.2 Drying 57 Test procedure .58 Calculation of results 59 Evaluation of results .510 Test report 5BS EN 772-21:2011EN 772-21:2011 (E) 3 Foreword This document (EN 772-21:2011) has been prepared by Te
12、chnical Committee CEN/TC 125 “Masonry”, the secretariat of which is held by BSI. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by November 2011, and conflicting national standards shall be withdraw
13、n at the latest by November 2011. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. According to the CEN/CENELEC Internal Regulations, t
14、he national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Nethe
15、rlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. BS EN 772-21:2011EN 772-21:2011 (E) 4 1 Scope This European Standard specifies a method of determining the water absorption of clay and calcium silicate masonry units by immersing them i
16、n cold water. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 771-1, Sp
17、ecification for masonry units Part 1: Clay masonry units EN 771-2, Specification for masonry units Part 2: Calcium silicate masonry units EN 771-3, Specification for masonry units Part 3: Aggregate concrete masonry units (Dense and light-weight aggregates) EN 771-4, Specification for masonry units P
18、art 4: Autoclaved aerated concrete masonry units EN 771-5, Specification for masonry units Part 5: Manufactured stone masonry units EN 771-6, Specification for masonry units Part 6: Natural stone masonry units 3 Principle After drying to constant mass a masonry unit is immersed in water for 24 h and
19、 the increase in mass is determined. 4 Symbols Md is the mass of the specimen after drying (g); Msis the mass of the specimen after soaking (g); Wsis the water absorption of the specimen (%). 5 Apparatus 5.1 Water tank large enough to contain all of the samples, supported off the base of the tank so
20、 that water is in contact with all the faces of the specimen. 5.2 Ventilated oven capable of maintaining a temperature of 105 C + 5 C. 5.3 Weighing instrument capable of weighing the specimens to an accuracy of 0,1 % of their mass when dry. BS EN 772-21:2011EN 772-21:2011 (E) 5 6 Preparation 6.1 Sam
21、pling The method of sampling shall be in accordance with the relevant part of EN 771. The minimum number of specimens shall be six, but a larger minimum number may be specified in the product specification, in which case that larger number shall be used. 6.2 Drying Dry the test specimens to constant
22、 mass Mdin a ventilated oven (5.2) at a temperature of 105 C + 5 C. Constant mass is reached if, during the drying process in two subsequent weighings with not less than a 24 h interval, the loss in mass between the two determinations is not more than 0,2 % of the total mass. Allow the specimens to
23、cool to ambient temperature before they are weighed. 7 Test procedure Place each unit in the tank of water. Leave clay units submerged for 24 h + 0,5 h. Leave calcium silicate units submerged for 48 h 0,5 h. Take the units from the tank and remove any water from their surfaces using a damp cloth or
24、sponge. Weigh the specimens and record their mass, Ms. 8 Calculation of results Calculate the water absorption Wsof each of the units to the nearest 1 %. Ws= ddsMMM x 100 % 9 Evaluation of results Calculate the mean water absorption to the nearest 1 %. 10 Test report The test report shall contain th
25、e following information: a) number , title and date of issue of this European Standard; b) name of the organization that carried out the sampling and the method used; c) date of testing; d) description of the specimens to EN 771-1 or EN 771-2 as is relevant; e) number of specimens in the sample; BS
26、EN 772-21:2011EN 772-21:2011 (E) 6 f) mass of each specimen dry and after soaking; g) soaking period in hours; h) individual and mean water absorption values to the nearest 1 %; i) remarks, if any. This page deliberately left blankBSI is the independent national body responsible for preparing Britis
27、h Standardsand other standards-related publications, information and services. It presents the UK view on standards in Europe and at the international level. It is incorporated by Royal Charter.British Standards Institution (BSI)raising standards worldwideBSI Group Headquarters389 Chiswick High Road
28、 London W4 4AL UKTel +44 (0)20 8996 9001Fax +44 (0)20 8996 Standards are updated by amendment or revision. Users of British Stan-dards should make sure that they possess the latest amendments or editions.It is the constant aim of BSI to improve the quality of our products and serv-ices. We would be
29、 grateful if anyone finding an inaccuracy or ambiguity whileusing this British Standard would inform the Secretary of the technical com-mittee responsible, the identity of which can be found on the inside frontcover.Tel: +44 (0)20 8996 9001 Fax: +44 (0)20 8996 7001BSI offers Members an individual up
30、dating service called PLUS which ensuresthat subscribers automatically receive the latest editions of standards.Tel: +44 (0)20 8996 7669 Fax: +44 (0)20 8996 7001Email: Buying standardsYou may buy PDF and hard copy versions of standards directly using acredit card from the BSI Shop on the website ad
31、dition all orders for BSI, international and foreign standards publicationscan be addressed to BSI Customer Services.Tel: +44 (0)20 8996 9001 Fax: +44 (0)20 8996 7001Email: In response to orders for international standards, it is BSI policy tosupply the BSI implementation of those that have been pub
32、lishedas British Standards, unless otherwise requested.Information on standardsBSI provides a wide range of information on national, Europeanand international standards through its Knowledge Centre.Tel: +44 (0)20 8996 7004 Fax: +44 (0)20 8996 7005Email: Various BSI electronic information services ar
33、e also available whichgive details on all its products and services. Tel: +44 (0)20 8996 7111 Fax: +44 (0)20 8996 7048Email: BSI Subscribing Members are kept up to date with standardsdevelopments and receive substantial discounts on the purchase priceof standards. For details of these and other bene
34、fits contact Membership Ad-ministration. Tel: +44 (0)20 8996 7002 Fax: +44 (0)20 8996 7001 Email: Information regarding online access to British Standards via BritishStandards Online can be found at information about BSI is available on the BSI website at www.bsi- subsists in all BSI publications.
35、 BSI also holds the copyright,in the UK, of the publications of the international standardization bodies. Ex-cept as permitted under the Copyright, Designs and Patents Act 1988 no ex-tract may be reproduced, stored in a retrieval system or transmitted in anyform or by any means electronic, photocopy
36、ing, recording or otherwise without prior written permission from BSI. This does not preclude the freeuse, in the course of implementing the standard of necessary details such assymbols, and size, type or grade designations. If these details are to be usedfor any other purpose than implementation then the prior written permissionof BSI must be obtained. Details and advice can be obtained from the Copy-right & Licensing Manager.Tel: +44 (0)20 8996 7070Email:
