1、Methods of test for masonryPart 2: Determination of flexural strengthBS EN 1052-2:2016Incorporating corrigendum March 2017BSI Standards PublicationBS EN 1052-2:2016 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of EN 1052-2:2016, incorporating corrigendum March 2017
2、. It supersedes BS EN 1052-2:1999 which is withdrawn.The start and finish of text introduced or altered by corrigendum is indicated in the text by tags. Text altered by CEN corrigendum March 2017 is indicated in the text by g79g80.The UK participation in its preparation was entrusted to Technical Co
3、mmittee B/519, Masonry and associated testing.A list of organizations represented on this committee can be obtained on request to its secretary.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. The British Stan
4、dards Institution 2017. Published by BSI Standards Limited 2017ISBN 978 0 580 97006 1ICS 91.080.30Compliance with a British Standard cannot confer immunity from legal obligations.This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 March 2016.A
5、mendments/corrigenda issued since publicationDate Text affected30 April 2017 Implementation of CEN corrigendum March 2017EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 1052-2 March 2016 ICS 91.080.30 Supersedes EN 1052-2:1999 English Version Methods of test for masonry - Part 2: Determination
6、of flexural strength Mthodes dessai de la maonnerie - Partie 2: Dtermination de la rsistance la flexion Prfverfahren fr Mauerwerk - Teil 2: Bestimmung der Biegezugfestigkeit This European Standard was approved by CEN on 3 January 2016. CEN members are bound to comply with the CEN/CENELEC Internal Re
7、gulations which stipulate the conditions for giving this European Standard 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 CEN-CENELEC Management Centre or to any CEN me
8、mber. This European Standard exists in three official versions (English, French, German). A version in any 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.
9、 CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Polan
10、d, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. This document consolidates EN 1052-2:2016 and the corrigendum EN 1052-2:2016/AC:2017. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Mana
11、gement Centre: Avenue Marnix 17, B-1000 Brussels 2016 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 1052-2:2016 EEN 1052-2:2016(E) 2 Contents Page European foreword 3 1 Scope 4 2 Normative references 4 3 Principle . 4 4 Terms, de
12、finitions and symbols 4 4.1 Terms and definitions . 4 4.2 Symbols 5 5 Materials 5 5.1 Masonry units . 5 5.1.1 Conditioning of the units 5 5.1.2 Testing 5 5.2 Mortar . 5 6 Apparatus 6 7 Preparation of specimens 6 7.1 Masonry specimens 6 7.2 Construction and curing of the specimens 6 8 Procedure 7 8.1
13、 Placing the specimens in the testing equipment . 7 8.2 Loading . 7 8.3 Measurements and observations 9 8.4 Replications 10 9 Calculations . 10 10 Evaluation of results 10 11 Test report . 11 BS EN 1052-2:2016g8g17g3g883g882g887g884g487g884g483g884g882g883g888g525g8g526EN 1052-2:2016(E) 3 European f
14、oreword This document (EN 1052-2:2016) has been prepared by Technical 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 Septe
15、mber 2016, and conflicting national standards shall be withdrawn at the latest by September 2016. 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 pat
16、ent rights. This document supersedes EN 1052-2:1999. This document has been prepared under a mandate given to CEN by the European Commission and the European Free Trade Association. This document includes the corrigendum EN 1052-2:2016/AC:2017 which corrects 4.2, 8.1 and 8.3. According to the CEN/CE
17、NELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary,
18、Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. BS EN 1052-2:2016g8g17g3g883g882g887g884g487g884g483g884g882g883g888g525g8g526EN 1052-2:2016(E) 4 1 Scope This
19、 European standard specifies a method for determining the flexural strength of small masonry specimens for the two principal axes of loading. Guidance is given on the preparation of the specimens, the conditioning required before testing, the testing machine, the method of test, the method of calcul
20、ation and the contents of the test report. 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 amen
21、dments) applies. EN 772-1, Methods of test for masonry units Part 1: Determination of compressive strength EN 772-10, Methods of test for masonry units Part 10: Determination of moisture content of calcium silicate and autoclaved aerated concrete units EN 998-2, Specification for mortar for masonry
22、Part 2: Masonry mortar EN 1015-3, Methods of test for mortar for masonry Part 3: Determination of consistence of fresh mortar (by flow table) EN 1015-7, Methods of test for mortar for masonry Part 7: Determination of air content of fresh mortar EN 1015-11, Methods of test for mortar for masonary Par
23、t 11: Determination of flexural and compressive strength of hardened mortar 3 Principle The flexural strength of masonry is derived from the strength of small specimens tested to destruction under four point loading. The maximum load achieved is recorded. The characteristic value, calculated from th
24、e maximum stresses achieved by the samples is considered to be the flexural strength of the masonry. 4 Terms, definitions and symbols 4.1 Terms and definitions For the purposes of this document, the following terms and definitions apply. 4.1.1 masonry assemblage of masonry units laid in a specified
25、pattern and jointed together with mortar 4.1.2 flexural strength of masonry strength of masonry in pure bending assuming a linear stress distribution of internal stresses BS EN 1052-2:2016g8g17g3g883g882g887g884g487g884g483g884g882g883g888g525g8g526EN 1052-2:2016(E) 5 4.2 Symbols For the purposes of
26、 this document, the following symbols apply. b is the height or width of a masonry specimen perpendicular to the direction of span, (mm) Fi, max is the maximum load applied to an individual masonry specimen, (N) fmean is the mean flexural strength of the masonry specimens, (N/mm2) fxi is the flexura
27、l strength of an individual masonry specimen, (N/mm2) fxk is the characteristic flexural strength of masonry, (N/mm2) hu is the height of masonry unit, (mm) k is the numerical factor ls is the length of a masonry specimen in the direction of span, (mm) lu is the length of masonry unit, (mm) l1 is th
28、e spacing of the outer bearings, (mm) l2 is the spacing of the inner bearings, (mm) l3 is the length of specimen outside the outer support (1/2(ls l1), (mm) deleted text n is the number of specimens s is the standard deviation of the log values tu w is the width of masonry unit, (mm) is the weight o
29、f the sample (N) x is the distance between the flexural crack in the specimen after testing and the nearer of the outer supports, (mm) 5 Materials 5.1 Masonry units 5.1.1 Conditioning of the units The conditioning of masonry units shall be as specified: Record the method of conditioning the units pr
30、ior to laying. Measure the moisture content by mass of autoclaved aerated concrete and calcium silicate masonry units in accordance with EN 772-10. Record the age of non-autoclaved concrete units at the time of testing the masonry specimens. 5.1.2 Testing Determine the compressive strength of a samp
31、le of masonry units, using the method given in EN 772-1. For non-autoclaved concrete units determine the compressive strength at the time of testing the masonry specimens. 5.2 Mortar The mortar, its mixing procedure and its flow value shall conform to the requirements of EN 998-2, unless otherwise s
32、pecified, and these shall be reported in the test report. Take representative samples of fresh mortar from the masons board to make mortar prisms, to determine the flow value in accordance with EN 1015-3, and to determine the air content in accordance BS EN 1052-2:2016g8g17g3g883g882g887g884g487g884
33、g483g884g882g883g888g525g8g526EN 1052-2:2016(E) 6 with EN 1015-7. Use the prism specimens to determine the mean compressive strength at the time of testing of the masonry specimens in accordance with EN 1015-11. 6 Apparatus A testing machine complying with the requirements given in Table 1, and acco
34、mmodating variations of plane. The testing machine shall have adequate capacity but the scale used shall be such that the ultimate load on the specimen exceeds one fifth of the full scale reading. The machine shall be provided with a load pacer or equivalent means to enable the load to be applied at
35、 the rate specified. The bearings shall be designed to ensure that contact is provided over the full width of the masonry, for example by using a hollow rubber bolster of at least 7 mm wall thickness and a 10 mm bore containing an 8 mm diameter steel rod. Table 1 Requirements for testing machines Ma
36、ximum permissible repeatability of forces as percentage of indicated force Maximum permissible mean error of forces as percentage of indicated force Maximum permissible error of zero force as percentage of maximum force of range 2,0 2,0 0,4 7 Preparation of specimens 7.1 Masonry specimens For each o
37、f the two principal axes of loading use at least five specimens according to Figure 1 having the sizes given in Table 2. The size of the masonry specimens shall be chosen so that the distance between the inner and outer bearings shall be not less than the thickness of the masonry specimen. The thick
38、ness of the specimen shall be equal to tuunless otherwise specified. Table 2 Specimen sizes for testing the flexural strength of masonry Direction hu mm b mm Additional conditions Flexural strength for a plane of failure parallel to the bed joints any g951 400 and g951 1,5 lu minimum 2 bed joints wi
39、thin l2 Flexural strength for a plane of failure perpendicular to the bed joints g950 250 g951 240 and g951 3hu minimum 1 head joint every course within l2 250 g951 1000 minimum 1 bed joint and minimum 1 head joint every course within l2 7.2 Construction and curing of the specimens Build the specime
40、ns within 30 min after completion of the conditioning of the units, using mortar mixed not more than one hour beforehand unless the mortar is designed to be used over a more prolonged period. Construct the specimens to the bond specified. Do not allow the work to be interrupted before completion. Im
41、mediately after building, pre-compress each specimen using a uniformly distributed mass to give a vertical stress between 2,5 10g9393N/mm2and 5,0 10g9393N/mm2; then cure the specimens, and maintain them undisturbed until testing. For other than lime-based mortar prevent the test specimens from dryin
42、g out during the curing period by close covering with polyethylene sheet, and maintain the specimens undisturbed until testing unless otherwise specified. Test each specimen at an age of BS EN 1052-2:2016g8g17g3g883g882g887g884g487g884g483g884g882g883g888g525g8g526EN 1052-2:2016(E) 7 28 days 1 day,
43、unless otherwise specified, and determine the compressive strength of the mortar at the same age, following EN 1015-11. For lime-based mortars an alternative curing regime and period may be necessary and this should be specified. 8 Procedure 8.1 Placing the specimens in the testing equipment Test th
44、e masonry specimen in the vertical attitude under four-point loading (see Figure 1). As an alternative, the specimen can be tested in a horizontal position. If the specimens are to be tested horizontally, determine the weight of each specimen to the nearest 1 N. The distance between the outer bearin
45、gs and the end of the specimen shall be greater than or equal to 15 mm. The distance between the inner bearings may be varied to suit the format of the masonry but shall be 0,4 times to 0,6 times the spacing of the outer bearings. The inner bearings shall be located so that they are, as far as pract
46、icable, midway between the nearest mortar joints which are parallel to the bearings. When testing in the vertical attitude ensure that the base of each masonry specimen is free from frictional restraint, for example by setting it on two layers of polytetrafluoroethylene with grease between them or o
47、n ball, needle or roller bearings. When testing in the horizontal attitude care is needed, especially with masonry of low flexural strength, to avoid failures in handling and placing in the test machine. It may be necessary to build extra test specimens to ensure that five valid results can be achie
48、ved. 8.2 Loading Increase the flexural stress at a rate between 0,03 N/mm2/min and 0,3 N/mm2/min. BS EN 1052-2:2016g8g17g3g883g882g887g884g487g884g483g884g882g883g888g525g8g526EN 1052-2:2016(E) 8 Dimensions in mm Key g132g947g884g142u and b g951 400 mm and hu g950 250 mm and more than two bed joints
49、 in l2 g132g947g886g138u and b g951 240 mm and hu g950 250 mm and a minimum of one head joint in l2 Flexural strength for a plane of failure parallel to the bed joints Flexural strength for a plane of failure perpendicular to the bed joints Key g132g947g883g481g887g142u and b g951 400 mm and hu g950 250 mm and two g132g947g886g138u and b g951 240 mm and hu g950 250 mm and a BS EN 1052-2:2016g8g17g3g883g882g887g884g487g884g483g884g882g883g888g525g8g526EN 1052-2:2016(E) 9 bed joints in l2 minimum of one head joint in l2 Flexural strength for
