BS EN 1741-1998 Determination of shear strength for out-of-plane forces of joints between prefabricated components made of autoclaved aerated concrete or lightweight aggregate conc.pdf

1、| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | BRITISH STANDARD BS EN 1741:1998 The Europ

2、ean Standard EN 1741:1998 has the status of a British Standard ICS 91.100.30 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW Determination of shear strength for out-of-plane forces of joints between prefabricated components made of autoclaved aerated concrete or lightweight ag

3、gregate concrete with open structureThis British Standard, having been prepared under the direction of the Sector Board for Building and Civil Engineering, was published under the authority of the Standards Board and comes into effect on 15 September 1998 BSI 1998 ISBN 0 580 30146 X BS EN 1741:1998

4、Amendments issued since publication Amd. No. Date Text affected National foreword This British Standard is the English language version of EN 1741:1998. The UK participation in its preparation was entrusted to Technical Committee B/523, Prefabricated components of reinforced autoclaved aerated concr

5、ete and lightweight aggregated concrete with open structure, which has the responsibility to: aid enquirers to understand the text; present to the responsible European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related internat

6、ional and European developments and promulgate them in the UK. A list of organizations represented on this committee can be obtained on request to its secretary. Cross-references The British Standards which implement international or European publications referred to in this document may be found in

7、 the BSI Standards Catalogue under the section entitled “International 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

8、 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 front cover, the EN title page, pages 2 to 6, an inside back cover and a back cover.CEN European

9、 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. Ref. No. EN 1741:1998 E EUROPEAN

10、STANDARD EN 1741 NORME EUROPE ENNE EUROPA ISCHE NORM April 1998 ICS Descriptors: Concrete, cellular concrete, aggregates, reinforcing materials, prefabricated elements, joints, mechanical tests, shear tests, determination, shear strength, test specimen English version Determination of shear strength

11、 for out-of-plane forces of joints between prefabricated components made of autoclaved aerated concrete or lightweight aggregate concrete with open structure De termination de la re sistance au cisaillement des jonctions entre les e le ments pre fabrique sr e alise s en be ton cellulaire autoclave o

12、u en be ton de granulats le gers a structure ouverte, sous leffet de forces agissant en dehors du plan des e le ments Bestimmung der Schubtragfa higkeit von Fugen zwischen vorgefertigten Bauteilen aus dampfgeha rtetem Porenbeton oder haufwerksporigem Leichtbeton bei Belastung rechtwinklig zur Bautei

13、lebene This European Standard was approved by CEN on 25 March 1998. 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 standard without any alteration. Up-to-date lists and bibliographica

14、l 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, German). A version in any other language made by translation under the responsibility of a CEN me

15、mber 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, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Por

16、tugal, Spain, Sweden, Switzerland and United Kingdom.Page 2 EN 1741:1998 BSI 1998 Foreword This European Standard has been prepared by Technical Committee CEN/TC 177, Prefabricated reinforced components of autoclaved aerated concrete or lightweight aggregate concrete with open structure, the secreta

17、riat of which is held by DIN. In order to meet the performance requirements as laid down in the product standards for prefabricated components of autoclaved aerated concrete and of lightweight aggregate concrete with open structure, a number of standardized test methods are necessary. This European

18、Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by October 1998, and conflicting national standards shall be withdrawn at the latest by October 1998. According to the CEN/CENELEC Internal Regulations, the national

19、 standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom. Conte

20、nts Page Foreword 2 1 Scope 3 2 Normative references 3 3 Principle 3 4 Apparatus 3 5 Test specimens 3 5.1 Sample 3 5.2 Shape and size of test specimens 3 5.3 Number of test specimens 3 5.4 Preparation of test specimens 5 5.5 Conditioning of test specimens 5 6 Testing procedure 5 6.1 Shear test 5 6.2

21、 Investigations after shear test 6 7 Test results 6 8 Test report 6Page 3 EN 1741:1998 BSI 1998 1 Scope This European Standard specifies a method of determining the shear strength for out-of-plane forces of joints between prefabricated components made of autoclaved aerated concrete (AAC) according t

22、o prEN 12602 or lightweight aggregate concrete with open structure (LAC) according to prEN 1520. 2 Normative references This European Standard incorporates by dated or undated reference, provisions from other publications. These normative references are cited at the appropriate places in the text, a

23、nd 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. For undated references the latest edition of the publication referred to applies.

24、EN 678, Determination of dry density of autoclaved aerated concrete. EN 679, Determination of the compressive strength of autoclaved aerated concrete. EN 992, Determination of dry density of lightweight aggregate concrete with open structure. EN 1353, Determination of moisture content of autoclaved

25、aerated concrete. EN 1354, Determination of compressive strength of lightweight aggregate concrete with open structure. EN 1356:1996, Performance test for prefabricated reinforced components made of autoclaved aerated concrete or lightweight aggregate concrete with open structure under transverse lo

26、ad. prEN 1520, Prefabricated components of lightweight aggregate concrete with open structure. prEN 12602, Prefabricated reinforced components of autoclaved aerated concrete. 3 Principle The shear strength of longitudinal joints between prefabricated AAC- or LAC-components for forces acting perpendi

27、cular to the plane of the components is determined by applying a vertical line load along the middle-axis on top surface of a horizontally positioned section of a component. The loaded section is supported at both longitudinal edges. At least one of these longitudinal supports consists of an adjacen

28、t component section connected to the loaded section by a joint of the type to be tested. The load is increased continuously or in steps until failure of the joint occurs. The test can be carried out without lateral restraints (case A) or with lateral restraints preventing in-plane displacements norm

29、al to the joint (case B). 4 Apparatus a) Saw, for cutting components and test specimens; b) Testing machine or jack, capable of applying a vertical compressive load without shock continuously or in steps. The precision of the machine or jack and of the load indication shall be such that the failure

30、load can be determined to an accuracy of 3 %. The measuring range shall be such that the failure load is higher than one-tenth of the range used; c) Callipers and/or a rule, capable of reading the dimensions of the test specimens and the joints to an accuracy of 1 mm; d) Devices, according to Figure

31、s 1, 2, and 3 for loading and supporting the test specimen; e) Weighing equipment, capable of determining the mass of the sections to an accuracy of 5 kg; f) Steel plates and rollers, according to Figures 1, 2 and 3; g) Device for measuring the relative vertical displacement between the joined secti

32、ons (optional). 5 Test specimens 5.1 Sample The sample for the preparation of the test specimens shall be taken in such a manner that it is representative of the product to be investigated. In the case of AAC, the direction of rise of the mass during manufacture shall be marked on the components. 5.

33、2 Shape and size of test specimens A test specimen normally consists of an arrangement of three sections taken from prefabricated components with standard width and thickness which shall be joined in the intended manner (see Figure 1). The length of the sections shall be equal to their width. For ce

34、rtain investigations test specimens consisting of two sections may be used (see Figures 2 and 3). 5.3 Number of test specimens A test set shall consist of at least three test specimens, each normally made of three sections taken from the same component (see Figure 1). When testing an asymmetric join

35、t between two sections, two test sets with different arrangements of the sections with respect to loading and supports shall be carried out (see Figures 2 and 3).Page 4 EN 1741:1998 BSI 1998 a = b2 2h$ 100 mm is the maximum permitted gap g is the maximum permitted gap 1 2 3 Support frame Moveable su

36、pport rollers Upper supports 4 5 6 Lateral supports (only in case B) Load distribution beam Soft fibreboard or equalizing layer Figure 1 Arrangement of standard shear test a = b2 2h$ 100 mm 1 2 3 Support frame Moveable support rollers Upper supports 4 5 6 Lateral supports (only in case B) Load distr

37、ibution beam Soft fibreboard or equalizing layer Figure 2 Arrangement of one-sided shear test (type 1)Page 5 EN 1741:1998 BSI 1998 1 2 3 Support frame Moveable support rollers Upper supports 4 5 6 Lateral supports (only in case B) Load distribution beam Soft fibreboard or equalizing layer Figure 3 A

38、rrangement of one-sided shear test (type 2) 5.4 Preparation of test specimens AAC components shall be allowed to cool for at least 2 d after autoclaving before being assembled. LAC components shall be at least 21 d old before being assembled and at least 28 d at testing. The sections shall be cut to

39、 length from the components by means of a saw. Before jointing, length, thickness, and width of the sections shall be measured. The shape and dimensions of the longitudinal faces adjacent to the joint (e.g. tongue and groove) shall also be determined. If the components or sections are frozen or cold

40、, they shall be stored with sufficient space between each other at room temperature for at least 2 d before jointing. The sections shall then be arranged on a support frame according to Figure 1, 2 or 3. Each support consists of a roller with a diameter of 20 mm or more and a steel plate between the

41、 roller and the section. The supports shall extend over the full length of the test specimen. The steel plates shall have a width of (50 2) mm and a thickness of at least 10 mm. The section on which the load is applied shall be weighed prior to being jointed. The gap between the assembled sections s

42、hall have the maximum width permitted by the manufacturer. If a dry jointing system is used (e.g. tongue and groove joint), the sections shall be simply laid together without additional fixing. In the case of joints to be grouted with mortar or concrete, the sections shall be placed in position and

43、fixed temporarily together in at least two places before grouting. After hardening of the grouting material the restraint shall be removed. Grouting shall be performed according to the instructions of the manufacturer of the components. The grouting procedure (including e.g. any prewetting of the co

44、ncrete adjacent to the joint), the recipe, consistency, and the temperature of the grouting material shall be recorded in the test report. A grouted joint shall be protected against moisture loss under plastic foil immediately after grouting and cured at room temperature for at least 7 d before the

45、test. 5.5 Conditioning of test specimens The test specimens shall be kept at room temperature before and during testing. The mass-related moisture content of the concrete at testing shall be at least 10 % for AAC and at least 5 % for LAC. This shall be checked after the shear test (see 6.2). NOTE Wh

46、en in doubt about the moisture content, this can be estimated in advance by testing related samples of material. 6 Testing procedure 6.1 Shear test The load shall be applied as line load acting in a vertical direction parallel to the joints and along the longitudinal axis of the section to be loaded

47、. It shall be uniformly distributed over the whole length of the test specimen and have a width equal to the width of the loaded section less twice its thickness, but not less than 100 mm, by means of a distribution beam and an intermediate layer of soft fibre board.Page 6 EN 1741:1998 BSI 1998 The

48、load shall be applied continuously or in steps until failure of a joint. In the case of incremental loading, the size of the load steps shall not exceed 1/10 of the estimated failure load. For each step the load may be increased rapidly, but without shock. After reaching the intended load level, the

49、 load shall be kept constant for 1 min before the next load step is applied. The total duration of the shear test should be approximately 10 min. The formation of cracks or irregularities and the rupture load shall be noted in the test report. If required, the relative vertical displacement between the joined sections should be measured. 6.2 Investigations after shear test Observations on the extent of filling of grouted joints shall be indicated in the test report. Samples shall be taken from the sections in the vicinit