1、BS EN 302-8:2017Adhesives for load-bearingtimber structures TestmethodsPart 8: Static load test of multiple bond linespecimens in compression shearBSI Standards PublicationWB11885_BSI_StandardCovs_2013_AW.indd 1 15/05/2013 15:06BS EN 302-8:2017 BRITISH STANDARDNational forewordThis British Standard
2、is the UK implementation of EN 302-8:2017. It supersedes BS EN 15416-2:2007 which is withdrawn.The UK participation in its preparation was entrusted to Technical Committee PRI/52, Adhesives.A list of organizations represented on this committee can be obtained on request to its secretary.This publica
3、tion does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. The British Standards Institution 2017.Published by BSI Standards Limited 2017ISBN 978 0 580 85715 7 ICS 83.180 Compliance with a British Standard cannot confer immunity fr
4、om legal obligations.This British Standard was published under the authority of the Standards Policy and Strategy Committee on 28 February 2017.Amendments/corrigenda issued since publicationDate T e x t a f f e c t e dBS EN 302-8:2017EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 302-8 January
5、 2017 ICS 83.180 Supersedes EN 15416-2:2007English Version Adhesives for load-bearing timber structures - Test methods - Part 8: Static load test of multiple bond line specimens in compression shear Adhsifs pour structures portantes en bois - Mthodes dessai - Partie 8 : Essai de charge statique sur
6、des prouvettes joints multiples en cisaillement par compression Klebstoffe fr tragende Holzbauteile - Prfverfahren - Teil 8: Statische Belastungsprfung an Prfkrpern mit mehreren Klebstofffugen bei Druck-Scherbeanspruchung This European Standard was approved by CEN on 30 October 2016. CEN members are
7、 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 bibliographical references concerning such national standards may be obtained on application to t
8、he CEN-CENELEC Management Centre 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 member into its own language and notified to the CEN-CENELEC Management Cen
9、tre has the same status as the official versions. 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, Lithuan
10、ia, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix
11、17, B-1000 Brussels 2017 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 302-8:2017 EBS EN 302-8:2017EN 302-8:2017 (E) 2 Contents Page European foreword . 3 Introduction 5 1 Scope 6 2 Normative references 6 3 Principle . 6 4 Appara
12、tus . 6 4.1 Test jig . 6 4.2 Equipment for climate control . 9 4.3 Testing machine 9 5 Test specimens . 9 5.1 Selection of wood 9 5.2 Preparation of laminations . 9 5.3 Preparation of test specimens . 12 6 Test procedure 12 6.1 Application of load . 12 6.2 Test climates 13 6.3 Measurements and evalu
13、ation of result 13 7 Test report 13 Bibliography . 15 BS EN 302-8:2017EN 302-8:2017 (E) 3 European foreword This document (EN 302-8:2017) has been prepared by Technical Committee CEN/TC 193 “Adhesives”, the secretariat of which is held by AENOR. This European Standard shall be given the status of a
14、national standard, either by publication of an identical text or by endorsement, at the latest by July 2017, and conflicting national standards shall be withdrawn at the latest by July 2017. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
15、 rights. CEN shall not be held responsible for identifying any or all such patent rights. This document supersedes EN 15416-2:2007. Compared to EN 15416-2:2007, the following modifications have been made: a) title has been changed; b) EN 301 and EN 16254 are included in the scope; c) introduction of
16、 (50 2) C and (90 2) C in Table 1, climate 1, with reference to EN 15425; d) layout has been made in line with EN 302-1:2013 to EN 302-7:2013; e) new drawings of the test jig with some adjusted part dimensions are included. This document is one of a package dealing with adhesives for use with timber
17、 structures, and is published in support to EN 1995, Eurocode 5: Design of timber structures (all parts). The package consists of three classification and performance requirements for adhesives for load-bearing timber structures; phenolic and aminoplastic adhesives (EN 301), one component polyuretha
18、ne adhesives (EN 15425) and emulsion polymerized isocyanate adhesives (EN 16254), and twelve test methods (EN 302 parts 1 to 8, EN 15416 parts 1, 3, 4 and 5). These European Standards have the following titles: EN 301, Adhesives, phenolic and aminoplastic, for load-bearing timber structures Classifi
19、cation and performance requirements EN 15425, Adhesives One component polyurethane (PUR) for load-bearing timber structures - Classification and performance requirements EN 16254, Adhesives Emulsion polymerized isocyanate (EPI) for load-bearing timber structures Classification and performance requir
20、ements EN 302-1, Adhesives for load-bearing timber structures Test methods Part 1: Determination of longitudinal tensile shear strength EN 302-2, Adhesives for load-bearing timber structures Test methods Part 2: Determination of resistance to delamination BS EN 302-8:2017EN 302-8:2017 (E) 4 EN 302-3
21、, Adhesives for load-bearing timber structures Test methods Part 3: Determination of the effect of acid damage to wood fibres by temperature and humidity cycling on the transverse tensile strength EN 302-4, Adhesives for load-bearing timber structures Test methods Part 4: Determination of the effect
22、s of wood shrinkage on the shear strength EN 302-5, Adhesives for load-bearing timber structures Test methods Part 5: Determination of maximum assembly time under referenced conditions EN 302-6, Adhesives for load-bearing timber structures Test methods Part 6: Determination of the minimum pressing t
23、ime under referenced conditions EN 302-7, Adhesives for load-bearing timber structures Test methods Part 7: Determination of the working life under referenced conditions EN 302-8, Adhesives for load-bearing timber structures Test methods Part 8: Static load test of multiple bond line specimens in co
24、mpression shear EN 15416-1, Adhesives for load bearing timber structures other than phenolic and aminoplastic Test methods Part 1: Long-term tension load test perpendicular to the bond line at varying climate conditions with specimens perpendicular to the glue line (Glass house test) EN 15416-3, Adh
25、esives for load bearing timber structures other than phenolic and aminoplastic Test methods Part 3: Creep deformation test at cyclic climate conditions with specimens loaded in bending shear EN 15416-4, Adhesives for load bearing timber structures other than phenolic and aminoplastic Test methods Pa
26、rt 4: Determination of open assembly time under referenced conditions EN 15416-5, Adhesives for load bearing timber structures other than phenolic and aminoplastic Test methods Part 5: Determination of minimum pressing time under referenced conditions According to the CEN-CENELEC Internal Regulation
27、s, the national standards organisations 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, Iceland, Ireland, Italy,
28、Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. BS EN 302-8:2017EN 302-8:2017 (E) 5 Introduction Safety statement Persons using this European Standard should be familiar with
29、the normal laboratory practice, if applicable. This European Standard cannot address all of the safety problems, if any, associated with its use. It is the responsibility of the user to establish appropriate safety and health practices and to ensure compliance with any regulatory conditions. Environ
30、mental statement It is understood that some of the material permitted in this European Standard may have negative environmental impact. As technological advantages lead to better alternatives for these materials, they will be eliminated from this European Standard to the extent possible. At the end
31、of the test, it is recommended that the user of this European Standard take care to carry out an appropriate disposal of the wastes, according to local regulation. BS EN 302-8:2017EN 302-8:2017 (E) 6 1 Scope This European Standard specifies a method of determining the ability of adhesive bonds to re
32、sist static load. It is applicable to adhesives used in load bearing timber structures. It is suitable for the following applications: a) for assessing the compliance of adhesives according to EN 301, EN 15425 and EN 16254; b) for assessing the suitability and quality of adhesives for load-bearing t
33、imber structures; c) for assessing the effect on the bond strength resulting from constant load at different climate conditions. This method is intended primarily to obtain performance data for the classification of adhesives for load bearing timber structures according to their suitability for use
34、in defined climatic environments. This method is not intended to provide data for structural design, and does not necessarily represent the performance of the bonded member in service. 2 Normative references The following documents, in whole or in part, are normatively referenced in this document an
35、d are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 301:2013, Adhesives, phenolic and aminoplastic, for load-bearing timber structures Classificatio
36、n and performance requirements EN 15425:2017, Adhesives One component polyurethane (PUR) for load-bearing timber structures Classification and performance requirements EN 16254:2013+A1:2016, Adhesives Emulsion polymerized isocyanate (EPI) for load-bearing timber structures Classification and perform
37、ance requirements 3 Principle Bonded test pieces are subjected to a constant compression shear load under a series of three different climates. Number of failures and the amount of deformation is measured after the end of the last climate cycle. 4 Apparatus 4.1 Test jig The test Equipment is shown i
38、n Figure 1 and Figure 2. BS EN 302-8:2017EN 302-8:2017 (E) 7 Dimensions in millimetres Key 1 top plate 2 spacer plate 3 base plate 4 tension rod 5 centre rod Figure 1 Test jig BS EN 302-8:2017EN 302-8:2017 (E) 8 Dimensions in millimetres Key 1 top plate 3 base plate 2 spacer plate 4 tension rod (the
39、 given lengths are minimum values) 5 centre rod. (the given length is a minimum value) Figure 2 Dimensions of plates and rods BS EN 302-8:2017EN 302-8:2017 (E) 9 If longer rods are used, distance blocks need to be placed on top and/or under the specimen. The distance blocks shall be prepared in such
40、 a way that the two contact surfaces, between the distance block and the jig and between the distance block and the specimen, are parallel. Dimension of distance blocks: at least 48 mm 51 mm 10 mm. NOTE Blocks produced from several pieces of plywood bonded together have been found suitable The sprin
41、g shall have the following characteristics: outside diameter (unloaded): 105 mm; end fix: both ends fixed and grounded; free length: 320 mm; compression at maximum load: 45 mm to 50 mm. NOTE A spring rate of 81 N/mm has shown to be suitable. 4.2 Equipment for climate control The used equipment shall
42、 be capable of maintaining (50 2) C, (70 2) C or (90 2) C with a relative humidity of (10 5) % in order to reach one of the climate conditions 1 a), 1 b) or 1 c) in Table 1, and the two climates (20 2) C and (85 5) % relative humidity and (50 2) C and (75 5) % relative humidity. 4.3 Testing machine
43、A testing machine capable to apply a compression load is required. 5 Test specimens 5.1 Selection of wood Untreated beech wood (Fagus sylvatica L.) with a density of (700 50) kg/m3at 12 % moisture content shall be used. The material shall be straight-grained and free from knots, machining defects (s
44、uch as chipped grain, dubbed ends, feed roll polish, coarse knife marks and feed roll compression) and any drying defects such as case hardening, collapse, splits or checks. The angle of the annual rings to the surface to be bonded shall be between 30 and 60. 5.2 Preparation of laminations Condition
45、 the wood at (20 2) C and (65 5) % relative humidity (hereafter climate 20/65 until a moisture content of (12 1) % has been obtained. Plane each lamination not more than 4 h before applying the test adhesive. The parts, of which the specimen is built of, shall have the same direction for the annual
46、rings in the cross section (according to Figure 3). BS EN 302-8:2017EN 302-8:2017 (E) 10 Figure 3 Orientation of annual rings in cross section of lamination Three laminated wood members shall be prepared in order to produce six test samples. The laminated members shall be prepared from boards (16,0
47、0,1) mm thick (after planing) by (60,0 0,1) mm wide by (305,0 0,1) mm along the grain. Each laminated member shall be made from two outer lamellas as above and alternate spacers and wood sections for the inner part. The wood sections shall be sliced from a third board identical to those above. The w
48、ood sections shall be (28,5 0,1) mm along the grain by (16,0 0,1) mm thick by (60,0 0,1) mm wide (according to Figure 4). Spacers shall be made of suitable material, which makes it possible to remove them without destroying the specimen or disturb the positioning of the central pieces. Dimension of
49、spacers: length (6,4 0,1) mm, thickness slightly less than the mid-section pieces, width (60,0 0,1) mm. NOTE Spacers made from PTFE have shown to be a suitable material. BS EN 302-8:2017EN 302-8:2017 (E) 11 Dimensions in millimetres Dimensions in millimetres Figure 4 Test specimen layers prior to bonding Figure 5 Test specimen after bonding and planing The centre layer of the assembly shall be m
