1、BRITISH STANDARD BS EN 538:1994 Clay roofing tiles for discontinuous laying Flexural strength test The European Standard EN 538:1994 has the status of a British Standard UDC 691.424.666.74:620.17BSEN 538:1994 This British Standard, having been prepared under the directionof Technical Committee B/542
2、, was published under theauthority of the Standards Board and comes into effect on 15December 1994 BSI 08-1999 The following BSI references relate to the work on this standard: Committee reference B/542/3 Draft for comment 91/16433 DC ISBN 0 580 23104 6 Cooperating organizations The European Committ
3、ee for Standardization (CEN), under whose supervision this European Standard was prepared, comprises the national standards organizations of the following countries: Austria Oesterreichisches Normungsinstitut Belgium Institut belge de normalisation Denmark Dansk Standard Finland Suomen Standardisoim
4、isliito, r.y. France Association franaise de normalisation Germany Deutsches Institut fr Normung e.V. Greece Hellenic Organization for Standardization Iceland Technological Institute of Iceland Ireland National Standards Authority of Ireland Italy Ente Nazionale Italiano di Unificazione Luxembourg I
5、nspection du Travail et des Mines Netherlands Nederlands Normalisatie-instituut Norway Norges Standardiseringsforbund Portugal Instituto Portugus da Qualidade Spain Asociacin Espaola de Normalizacin y Certificacin Sweden Standardiseringskommissionen i Sverige Switzerland Association suisse de normal
6、isation United Kingdom British Standards Institution Amendments issued since publication Amd. No. Date CommentsBSEN 538:1994 BSI 08-1999 i Contents Page Cooperating organizations Inside front cover National foreword ii Foreword 2 Text of EN 538 3 National annex NA (informative) Committees responsibl
7、e Inside back cover National annex NB (informative) Cross-references Inside back coverBSEN 538:1994 ii BSI 08-1999 National foreword This British Standard has been prepared under the direction of Technical Committee B/542, Roofing and cladding products for discontinuous laying, and is the English la
8、nguage version of EN 538:1994, Clay roofing tiles for discontinuous laying Flexural strength test, published by the European Committee for Standardization (CEN). EN 538 partially replaces BS 402:1990, which will be withdrawn in due course. EN 538 was produced as a result of international discussions
9、 in which the UK took an active part. 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 Standard does not of itself confer immunity from legal obligations. Sum
10、mary of pages This document comprises a front cover, an inside front cover, pages i and ii, theEN title page, pages 2 to 8, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment tab
11、le on the inside front cover.EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 538 May 1994 UDC 691.424.666.74:620.17 Descriptors: Ceramics, roofing tiles, determination, flexural strength, break strength English version Clay roofing tiles for discontinuous laying Flexural strength test Tuiles de
12、 terre cuite pour pose en discontinu Dtermination de la rsistance la rupture par flexion Tondachziegel fr berlappende Verlegung Prfung der Biegetragfhigkeit This European Standard was approved by CEN on 1994-05-18. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipu
13、late 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 Central Secretariat or to any CEN member. This European Standard ex
14、ists 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 Central Secretariat has the same status as the official versions. CEN members are the national standards b
15、odies of Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. CEN European Committee for Standardization Comit Europen de Normalisation Europisches Komitee fr Normung Central Se
16、cretariat: rue de Stassart 36, B-1050 Brussels 1994 Copyright reserved to CEN members Ref. No. EN 538:1994 EEN 538:1994 BSI 08-1999 2 Foreword This European Standard has been prepared by CEN/TC 128, Roof covering products for discontinuous laying, the Secretariat of which is held by ON. This Europea
17、n 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 1994, and conflicting national standards shall be withdrawn at the latest by November 1994. According to the CEN/CENELEC Internal Regulations, the foll
18、owing countries are bound to implement this European Standard: Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland, United Kingdom. Contents Page Foreword 2 1 Scope 3 2 Normative references 3 3 Sy
19、mbols and abbreviations 3 4 Test principle 3 5 Samples 3 6 Apparatus 3 7 Test procedure 3 7.1 Plain tiles 3 7.2 Tiles with sidelock and headlock, tiles with sidelock only, and overlapping tiles 4 7.3 Over and under tiles 4 7.3.1 Tiles without nibs 4 7.3.2 Tiles with nib(s) with or without flat botto
20、m 4 8 Test report 8 Figure 1 Test principle 3 Figure 2 Test for plain tiles 4 Figure 3 Test method for interlocking tiles 5 Figure 4.1 Test with contoured hardwood shim 5 Figure 4.2 Test with contoured hardwood shim (variation for tiles with no flat area) 6 Figure 5.1 Test with moulded plaster shim
21、6 Figure 5.2 Test with moulded plaster shim (variation) 7 Figure 6 Test on over and under tiles without nibs 7 Figure 7 Test for over and under tiles with nibs not resting on one generatrix 8 Figure 8 Test for over and under tiles with nibs resting on one generatrix only 8EN 538:1994 BSI 08-1999 3 1
22、 Scope This European Standard describes the test method used to evaluate the flexural strength of clay roofing tiles as defined in the standard EN1304 Clay roofing tiles Product definitions and specifications. Other physical characteristics are dealt with by the standard EN539 Clay roofing tiles Det
23、ermination of physical characteristics:Impermeability and frost resistance. 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 and the publications a
24、re 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. EN 1304, Clay roofin
25、g tiles Product definitions and specifications 1) . EN 539, Clay roofing tiles Determination of physical characteristics. EN 539-1, Impermeability test. EN 539-2, Frost tests 1) . ISO 48:1979, Vulcanized rubbers Determination of hardness (Hardness between30and85IRHD). 3 Symbols and abbreviations 4 T
26、est principle Verification of the ability of the product to resist a centred load when subjected to flexion on two simple bearers. 5 Samples The evaluation of flexural strength is made on ten samples each one consisting of a whole tile dried in ambient air. If the tiles have been subjected to humidi
27、ty, they shall be dried in a laboratory atmosphere before testing (temperature+10 C and+40 C, relative humidity less than90%). 6 Apparatus The apparatus consists of: a device that applies a load with an accuracy of2% and a load increase rate of0.05kN/s; a system used as lower bearers and, depending
28、on the type of tile, either made up of rods or half-rods, one of which is articulated in order to rotate in a vertical plane and obtain as uniform a load distribution as possible on the sample, or for some over and under tiles by a flat plate supporting the tile; a round steel bar fitted to the bott
29、om of the load application device. The upper and lower bearers shall have a radius of between15mm and20mm and a length greater than the width of the tile to be tested; a set of hardwood shims used for chocking the lower bearers as defined in7.2; a hardwood shim adapted to the shape of the tile as de
30、fined in7.2, should this chocking system be preferred to the plaster shim type; For apparatus where the weight of the tile and fittings is taken into account when reading the load, the corresponding tare is not included in the failure load value. 7 Test procedure 7.1 Plain tiles Place the tile on th
31、e two lower bearers (seeFigure 2) so that: the first bearer is in the position normally occupied by the batten; the second bearer is separated from the first by a distance equal to two thirds of the overall length (L) of the tile. Place this assembly in such a position that the load application bar
32、is parallel to the two lower bearers and equidistant from both. Note the distance between the bearer axes. Apply the test load progressively at a rate of not more than0,05kN/s until the sample fails. 1) In preparation. L Overall length of tile F Load at failure Figure 1 Test principleEN 538:1994 4 B
33、SI 08-1999 Note the value (F) of the load at failure, expressed inkN and rounded off to two decimal points. 7.2 Tiles with sidelock and headlock, tiles with sidelock only and overlapping tiles Place the tile on the two lower bearers in the same horizontal plane (seeFigure 3) so that: the first beare
34、r is in the position normally occupied by the batten; the second bearer is separated from the first by a distance equal to two-thirds of the overall length (L) of the tile. In order to ensure that the tile remains in a stable position, use wooden shims of the same width as the upper shim to support
35、the tile on the lower bearers, and a shim adapted to fit the shape of the tile for the upper bearer. This upper support can be obtained either by using a contoured hardwood shim (Figure 4.1 and Figure 4.2) or a moulded plaster one (Figure 5.1 andFigure 5.2) to keep the load application bar horizonta
36、l. The contoured piece of wood has a strip of rubber on the part in contact with the tile. This 5mm-thick strip shall have a specified IRHD hardness50 5, measured as per ISO48:1979. The width of the contoured hardwood shim or moulded plaster shim shall be equal to the diameter of the load applicatio
37、n bar. Place the assembly in such a position that the load application bar is parallel to the two lower bearers and equidistant from both. Note the distance between the bearer axes. Apply the load progressively at a rate of0,05kN/s until the sample fails. Note the value (F) of the load at failure, e
38、xpressed inkN, and rounded off to the nearest two decimal points. 7.3 Over and under tiles 7.3.1 Tiles without nibs Place the tile, with its concavity facing downward in a horizontal position, on the plate of the apparatus so that the load application bar is in contact with the tiles upper generatri
39、x and the bars horizontal pin is approximately halfway between the two ends of the tile (seeFigure 6). Apply the load progressively at a rate of approximately0,05kN/s until the sample fails. Note the value (F) of the load at failure, expressed inkN and rounded off to the nearest two decimal points.
40、Determine the average load at failure as the arithmetical mean of ten readings expressed in kN and rounded off to two decimal points. 7.3.2 Tiles with nib(s) with or without flat bottom Place the tile on the two lower bearers (seeFigure 7andFigure 8) so that: the first bearer is in the position norm
41、ally occupied by the batten; the second bearer is separated from the first by a distance equal to two-thirds of the overall length (L) of the tile. In the case of tiles that lie only on one generatrix, hold the sample in place by using shims at one end (see diagram for method, Figure 8). Place the a
42、ssembly in such a position that the load application bar is parallel to the two lower bearers and equidistant from both. Note the distance between the bearer axes. Apply the load progressively at a rate of approximatively0,05kN/s until the sample fails. Note the value (F) of the load at failure, exp
43、ressed inkN and rounded off to the nearest two decimal points. Determine the average load at failure as the arithmetical mean of ten readings expressed in kN and rounded off to the nearest two decimal points. Figure 2 Test for plain tilesEN 538:1994 BSI 08-1999 5 Figure 3 Test method for interlockin
44、g tiles Figure 4.1 Test with contoured hardwood shimEN 538:1994 6 BSI 08-1999 Figure 4.2 Test with contoured hardwood shim (variation for tiles with no flat area) Figure 5.1 Test with moulded plaster shimEN 538:1994 BSI 08-1999 7 Figure 5.2 Test with moulded plaster shim (variation) Figure 6 Test on
45、 over and under tiles without nibsEN 538:1994 8 BSI 08-1999 8 Test report The test report shall specify: the European standard number, EN538; the name of the test laboratory; the date on which the laboratory received the sample; the test date; a description and identification of the tile, including
46、the type, the length and the width, the manufacturers name and, where possible, the production date; the distance between the centres of the lower bearers, except for over and under tiles without nibs; the load at failure for each tile, expressed to the nearest0.01kN; the minimum load registered at
47、failure; the mean load at failure; comments if necessary; signature of the person responsible for the test. NOTEA tiles flexural strength depends on its shape. Consequently, the values indicated in the report cannot be compared directly from one type of tile to another. Figure 7 Test for over and un
48、der tiles with nibs not resting on one generatrix Figure 8 Test for over and under tiles with nibs resting on one generatrix onlyBSEN 538:1994 BSI 08-1999 National annex NA (informative) Committees responsible The United Kingdom participation in the preparation of this European Standard was entruste
49、d by Technical Committee B/542, Roofing and cladding products for discontinuous laying, to Subcommittee B/542/3, Clay roofing tiles, upon which the following bodies were represented: Clay Roofing Tile Council Department of the Environment (Building Research Establishment) National Clayware Federation National Federation of Roofing Contractors National House-building Council Royal Institution of British Architects National annex NB (informat
