Adhesives for load-bearing timber structures - Test methods - Part 4: Determination of the effects of wood shrinkage on the shear strength

This document specifies a method for determining the influence of shear strength in crosswise gluing by wood shrinkage under drying conditions.
It is applicable for the following applications:
a)   for assessing the compliance of adhesives with EN 301, EN 15425, EN 16254, EN 17334 and EN 17418;
b)   for assessing the suitability and quality of adhesives for load-bearing timber structures;
c)   for determining if the adhesive is capable of withstanding stresses due to wood shrinkage without unacceptable loss of strength.
This test is intended primarily to obtain performance data for the classification of adhesives for load-bearing timber structures according to their suitability for use in defined climatic environments. This test is carried out on Norway spruce (Picea abies L.).
This method is not intended to provide data for structural design and does not necessarily represent the performance of the bonded member in service.

Klebstoffe für tragende Holzbauteile - Prüfverfahren - Teil 4: Bestimmung des Einflusses von Holzschwindung auf die Scherfestigkeit

Dieses Dokument legt ein Verfahren zur Bestimmung des Einflusses von Holzschwindung unter Trocknungsbedingungen auf die Scherfestigkeit bei kreuzweiser Verklebung fest.
Es ist für folgende Anwendungsfälle geeignet:
a)   zur Beurteilung der Übereinstimmung von Klebstoffen mit EN 301, EN 15425, EN 16254, EN 17334 und EN 17418;
b)   zur Beurteilung der Eignung und Qualität von Klebstoffen für tragende Holzbauteile;
c)   zum Nachweis, ob der Klebstoff in der Lage ist, den Spannungen infolge Holzschwindung ohne unannehmbaren Festigkeitsverlust standzuhalten.
Diese Prüfung dient hauptsächlich der Ermittlung von Leistungswerten für die Klassifizierung von Klebstoffen für tragende Holzbauteile entsprechend ihrer Eignung zum Einsatz unter festgelegten klimatischen Bedingungen. Diese Prüfung wird mit Fichte (Picea abies L.) durchgeführt.
Dieses Verfahren ist nicht dafür vorgesehen, Bemessungswerte bereitzustellen, und gibt nicht zwangsläufig die Leistungsfähigkeit des verklebten Bauteiles im Gebrauch wieder.

Adhésifs pour structures portantes en bois - Méthodes d’essai - Partie 4 : Détermination de l’influence du retrait du bois sur la résistance au cisaillement

Le présent document spécifie une méthode qui permet de déterminer l’effet du retrait du bois dans des conditions de séchage sur la résistance au cisaillement de collages croisés.
Cette méthode s’applique dans les cas suivants :
a)   évaluation de la conformité des adhésifs aux EN 301, EN 15425, EN 16254, EN 17334 et EN 17418 ;
b)   évaluation de l’aptitude à l’emploi et de la qualité des adhésifs pour les structures portantes en bois ;
c)   détermination de la capacité des adhésifs à supporter des contraintes dues au retrait du bois sans perte de résistance inacceptable.
Cet essai vise principalement à obtenir des données de performance en vue de la classification des adhésifs pour structures portantes en bois en fonction de leur aptitude à l’utilisation dans des environnements climatiques définis. Cet essai est réalisé sur de l’épicéa de Norvège (Picea abies L.).
Cette méthode n’est pas destinée à fournir des données pour le calcul des structures et ne représente pas nécessairement les performances en service de l’élément collé.

Lepila za nosilne lesene konstrukcije - Preskusne metode - 4. del: Ugotavljanje vpliva krčenja lesa na strižno trdnost

General Information

Status
Published
Publication Date
30-May-2023
Current Stage
6060 - Definitive text made available (DAV) - Publishing
Start Date
15-Feb-2023
Due Date
09-Dec-2022
Completion Date
15-Feb-2023

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SLOVENSKI STANDARD
SIST EN 302-4:2023
01-april-2023
Lepila za nosilne lesene konstrukcije - Preskusne metode - 4. del: Ugotavljanje
vpliva krčenja lesa na strižno trdnost

Adhesives for load-bearing timber structures - Test methods - Part 4: Determination of

the effects of wood shrinkage on the shear strength

Klebstoffe für tragende Holzbauteile - Prüfverfahren - Teil 4: Bestimmung des Einflusses

von Holzschwindung auf die Scherfestigkeit

Adhésifs pour structures portantes en bois - Méthodes d’essai - Partie 4 : Détermination

de l’influence du retrait du bois sur la résistance au cisaillement
Ta slovenski standard je istoveten z: EN 302-4:2023
ICS:
83.180 Lepila Adhesives
91.080.20 Lesene konstrukcije Timber structures
SIST EN 302-4:2023 sl,en,fr

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
SIST EN 302-4:2023
---------------------- Page: 2 ----------------------
SIST EN 302-4:2023
EN 302-4
EUROPEAN STANDARD
NORME EUROPÉENNE
February 2023
EUROPÄISCHE NORM
ICS 83.180 Supersedes EN 302-4:2013
English Version
Adhesives for load-bearing timber structures - Test
methods - Part 4: Determination of the effects of wood
shrinkage on the shear strength

Adhésifs pour structures portantes en bois - Méthodes Klebstoffe für tragende Holzbauteile - Prüfverfahren -

d'essai - Partie 4 : Détermination de l'influence du Teil 4: Bestimmung des Einflusses von

retrait du bois sur la résistance au cisaillement Holzschwindung auf die Scherfestigkeit

This European Standard was approved by CEN on 18 December 2022.

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 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 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.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,

Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,

Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and

United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels

© 2023 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 302-4:2023 E

worldwide for CEN national Members.
---------------------- Page: 3 ----------------------
SIST EN 302-4:2023
EN 302-4:2023 (E)
Contents Page

European foreword ....................................................................................................................................................... 3

Introduction .................................................................................................................................................................... 4

1 Scope .................................................................................................................................................................... 6

2 Normative references .................................................................................................................................... 6

3 Terms and definitions ................................................................................................................................... 6

4 Symbols ............................................................................................................................................................... 7

5 Principle ............................................................................................................................................................. 7

6 Apparatus ........................................................................................................................................................... 7

7 Method ................................................................................................................................................................ 7

7.1 General ................................................................................................................................................................ 7

7.1.1 Selection of timber .......................................................................................................................................... 7

7.1.2 Preparation of cover pieces ......................................................................................................................... 8

7.1.3 Preparation of core pieces ........................................................................................................................... 8

7.1.4 Conditioning ...................................................................................................................................................... 8

7.2 Preparation of the bonded assemblies .................................................................................................... 9

7.3 Number of bonded assemblies ................................................................................................................ 11

7.4 Dry storage treatment ................................................................................................................................ 11

7.5 Preparation of the test piece .................................................................................................................... 11

7.6 Climatic storage ............................................................................................................................................ 12

7.7 Test procedure .............................................................................................................................................. 12

8 Expression of results ................................................................................................................................... 13

9 Test report ...................................................................................................................................................... 13

9.1 The adhesive .................................................................................................................................................. 13

9.2 Preparation of the samples and the testing procedures ................................................................ 13

9.3 Test results ..................................................................................................................................................... 14

---------------------- Page: 4 ----------------------
SIST EN 302-4:2023
EN 302-4:2023 (E)
European foreword

This document (EN 302-4:2023) has been prepared by Technical Committee CEN/TC 193 “Adhesives”,

the secretariat of which is held by UNE.

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 August 2023, and conflicting national standards shall

be withdrawn at the latest by August 2023.

Attention is drawn to the possibility that some of the elements of this document may be the subject of

patent rights. CEN shall not be held responsible for identifying any or all such patent rights.

This document supersedes EN 302-4:2013.
The main changes compared to the previous edition are listed below:
a) the list of standards in the Introduction has been updated;
b) two new standards, EN 17334 and EN 17418, have been included in the Scope;
c) two new clauses (Terms and definitions and Symbols) have been introduced;

d) preparation of samples with 0,3 mm and 2 mm glue line thickness has been added;

e) a new NOTE has been added at the end of 7.2;
f) the second paragraph in 7.6 has been changed;
g) nominal glue line thickness has been added in 9.2 c);
h) the Bibliography has been deleted.

Any feedback and questions on this document should be directed to the users’ national standards body.

A complete listing of these bodies can be found on the CEN website.

According to the CEN-CENELEC Internal Regulations, 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, France, Germany, Greece, Hungary, Iceland,

Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of

North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and the

United Kingdom.
---------------------- Page: 5 ----------------------
SIST EN 302-4:2023
EN 302-4:2023 (E)
Introduction

This document is one of a series dealing with adhesives for use with timber structures, and is published

in support of the EN 1995 series, Eurocode 5: Design of timber structures. The series consists of five

classification and performance requirements for adhesives for load-bearing timber structures, phenolic

and aminoplastic adhesives (EN 301), one component polyurethane adhesives (EN 15425), emulsion

polymer isocyanate adhesives (EN 16254), two component epoxy and polyurethane adhesives for glued

in rods (EN 17334) and for on-site repair of cracked timber structures (EN 17418) and all together

twelve test methods (EN 302-1, EN 302-2, EN 302-3, EN 302-4, EN 302-5, EN 302-6, EN 302-7,

EN 302-8, EN 15416-1, EN 15416-3, EN 15416-4 and EN 15416-5).
These European Standards have the following titles:

EN 301, Adhesives, phenolic and aminoplastic, for load-bearing timber structures — Classification and

performance requirements
EN 302, Adhesives for load-bearing timber structures — Test methods:
— Part 1: Determination of longitudinal tensile shear strength
— Part 2: Determination of resistance to delamination

— Part 3: Determination of the effect of acid damage to wood fibres by temperature and humidity

cycling on the transverse tensile strength
— Part 4: Determination of the effects of wood shrinkage on the shear strength
— Part 5: Determination of maximum assembly time under referenced conditions
— Part 6: Determination of the minimum pressing time under referenced conditions
— Part 7: Determination of the working life under referenced conditions
— Part 8: Static load test of multiple bond line specimens in compression shear

EN 15416, 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)

— Part 3: Creep deformation test at cyclic climate conditions with specimens loaded in bending shear

— Part 4: Determination of open assembly time under referenced conditions
— Part 5: Determination of minimum pressing time under referenced conditions

EN 15425, Adhesives — One component polyurethane (PUR) for load-bearing timber structures —

Classification and performance requirements

EN 16254, Adhesives — Emulsion polymer isocyanate (EPI) for load-bearing timber structures —

Classification and performance requirements
---------------------- Page: 6 ----------------------
SIST EN 302-4:2023
EN 302-4:2023 (E)

EN 17334, Glued-in rods in glued structural timber products — Testing, requirements and bond shear

strength classification

EN 17418, Two-component epoxy and polyurethane adhesives for on-site repair of cracked timber

structures — Testing, requirements and repair strength verification
Safety statement

Persons using this document should be familiar with the normal laboratory practice, if applicable. This

document 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.
Environmental statement

It is understood that some of the material permitted in this standard can have a negative environmental

impact. As technological advantages lead to better alternatives for these materials, they will be

eliminated from this standard to the greatest extent possible.

At the end of the test, it is recommended that the users of the standard take care to carry out an

appropriate disposal of the wastes, according to local regulations.
---------------------- Page: 7 ----------------------
SIST EN 302-4:2023
EN 302-4:2023 (E)
1 Scope

This document specifies a method for determining the influence of shear strength in crosswise gluing

by wood shrinkage under drying conditions.
It is applicable for the following applications:

a) for assessing the compliance of adhesives with EN 301, EN 15425, EN 16254, EN 17334 and

EN 17418;

b) for assessing the suitability and quality of adhesives for load-bearing timber structures;

c) for determining if the adhesive is capable of withstanding stresses due to wood shrinkage without

unacceptable loss of strength.

This test is intended primarily to obtain performance data for the classification of adhesives for load-

bearing timber structures according to their suitability for use in defined climatic environments. This

test is carried out on Norway spruce (Picea abies L.).

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 are referred to in the text in such a way that some or all of their content

constitutes requirements of this document. For dated references, only the edition cit

...

SLOVENSKI STANDARD
oSIST prEN 302-4:2021
01-november-2021
Nadomešča:
SIST EN 302-4:2013
Lepila za nosilne lesene konstrukcije - Preskusne metode - 4. del: Ugotavljanje
vpliva krčenja lesa na strižno trdnost

Adhesives for load-bearing timber structures - Test methods - Part 4: Determination of

the effects of wood shrinkage on the shear strength

Klebstoffe für tragende Holzbauteile - Prüfverfahren - Teil 4: Bestimmung des Einflusses

von Holzschwindung auf die Scherfestigkeit

Adhésifs pour structures portantes en bois - Méthodes d'essai - Partie 4: Détermination

de l'influence du retrait du bois sur la résistance au cisaillement
Ta slovenski standard je istoveten z: prEN 302-4
ICS:
83.180 Lepila Adhesives
91.080.20 Lesene konstrukcije Timber structures
oSIST prEN 302-4:2021 en

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
oSIST prEN 302-4:2021
---------------------- Page: 2 ----------------------
oSIST prEN 302-4:2021
DRAFT
EUROPEAN STANDARD
prEN 302-4
NORME EUROPÉENNE
EUROPÄISCHE NORM
September 2021
ICS 83.180 Will supersede EN 302-4:2013
English Version
Adhesives for load-bearing timber structures - Test
methods - Part 4: Determination of the effects of wood
shrinkage on the shear strength

Adhésifs pour structures portantes en bois - Méthodes Klebstoffe für tragende Holzbauteile - Prüfverfahren -

d'essai - Partie 4: Détermination de l'influence du Teil 4: Bestimmung des Einflusses von

retrait du bois sur la résistance au cisaillement Holzschwindung auf die Scherfestigkeit

This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee

CEN/TC 193.

If this draft becomes a European Standard, 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.

This draft European Standard was established by CEN 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.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,

Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,

Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and

United Kingdom.

Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are

aware and to provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without

notice and shall not be referred to as a European Standard.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels

© 2021 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 302-4:2021 E

worldwide for CEN national Members.
---------------------- Page: 3 ----------------------
oSIST prEN 302-4:2021
prEN 302-4:2021 (E)
Contents Page

European foreword ...................................................................................................................................................... 3

Introduction .................................................................................................................................................................... 4

1 Scope .................................................................................................................................................................... 6

2 Normative references .................................................................................................................................... 6

3 Terms and definitions ................................................................................................................................... 6

4 Symbols .............................................................................................................................................................. 7

5 Principle ............................................................................................................................................................. 7

6 Apparatus .......................................................................................................................................................... 7

7 Method ................................................................................................................................................................ 7

7.1 General................................................................................................................................................................ 7

7.2 Preparation of the bonded assemblies ................................................................................................... 9

7.3 Number of bonded assemblies ................................................................................................................ 11

7.4 Dry storage treatment ................................................................................................................................ 11

7.5 Preparation of the test piece ................................................................................................................... 11

7.6 Climatic storage ............................................................................................................................................ 12

7.7 Test procedure .............................................................................................................................................. 12

8 Expression of results .................................................................................................................................. 13

9 Test report ...................................................................................................................................................... 13

9.1 The adhesive .................................................................................................................................................. 13

9.2 Preparation of the samples and the testing procedures ............................................................... 13

9.3 Test results ..................................................................................................................................................... 13

Bibliography ................................................................................................................................................................ 15

---------------------- Page: 4 ----------------------
oSIST prEN 302-4:2021
prEN 302-4:2021 (E)
European foreword

This document (prEN 302-4:2021) has been prepared by Technical Committee CEN/TC 193 “Adhesives”,

the secretariat of which is held by UNE.
This document is currently submitted to the CEN Enquiry.
This document will supersede EN 302-4:2013.

In comparison with the previous edition, the following technical modifications have been made:

— list of standards in Introduction updated;
— two new standards, EN 17334 and EN 17418, have been included in the scope;
— two new clauses (Terms and definitions and Symbols) are introduced;

— preparation of samples with 0,3 mm and 2 mm glue line thickness has been added;

— the Bibliography has been deleted.
---------------------- Page: 5 ----------------------
oSIST prEN 302-4:2021
prEN 302-4:2021 (E)
Introduction

This document is one of a series dealing with adhesives for use with timber structures, and is published

in support of EN 1995, Eurocode 5: Design of timber structures. The series consists of five classification

and performance requirements for adhesives for load-bearing timber structures, phenolic and

aminoplastic adhesives (EN 301), one component polyurethane adhesives (EN 15425), emulsion

polymerised isocyanate adhesives (EN 16254), two component epoxy and polyurethane adhesives for

glued in rods (EN 17334) and for on-site repair of cracked timber structures (EN 17418) and all together

twelve test methods (EN 302 ( all parts), EN 15416-1, EN 15416-3, EN 15416-4 and EN 15416-5).

These European Standards have the following titles:

EN 301, Adhesives, phenolic and aminoplastic, for load-bearing timber structures — Classification and

performance requirements
EN 302, Adhesives for load-bearing timber structures — Test methods
— Part 1: Determination of longitudinal tensile shear strength
— Part 2: Determination of resistance to delamination

— Part 3: Determination of the effect of acid damage to wood fibres by temperature and humidity

cycling on the transverse tensile strength
— Part 4: Determination of the effects of wood shrinkage on the shear strength
— Part 5: Determination of maximum assembly time under referenced conditions
— Part 6: Determination of the minimum pressing time under referenced conditions
— Part 7: Determination of the working life under referenced conditions
— Part 8: Static load test of multiple bond line specimens in compression shear

EN 15416, 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 loaded perpendicular to the glue line (Glasshouse test)

— Part 3: Creep deformation test at cyclic climate conditions with specimens loaded in bending shear

— Part 4: Determination of open assembly time under referenced conditions
— Part 5: Determination of minimum pressing time under referenced conditions

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 requirements

EN 17334, Glued-in rods in glued structural timber products ― Testing, requirements, and bond shear

strength classification

EN 17418, Two-component epoxy and polyurethane adhesives for on-site repair of cracked timber

structures ― Testing, requirements, and repair strength verification
---------------------- Page: 6 ----------------------
oSIST prEN 302-4:2021
prEN 302-4:2021 (E)
Safety statement

Persons using this document should be familiar with the normal laboratory practice, if applicable. This

document 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.
Environmental statement

It is understood that some of the material permitted in this standard can have a negative environmental

impact. As technological advantages lead to better alternatives for these materials, they will be eliminated

from this standard to the greatest extent possible.

At the end of the test, it is recommended that the user of the standard take care to carry out an appropriate

disposal of the wastes, according to local regulations.
---------------------- Page: 7 ----------------------
oSIST prEN 302-4:2021
prEN 302-4:2021 (E)
1 Scope

This document specifies a method for determining the influence of shear strength in crosswise gluing by

wood shrinkage under drying conditions.
It is suitable for the following applications:

a) for assessing the compliance of adhesives with EN 301, EN 15425, EN 16254, EN 17334 and

EN 17418;

b) for assessing the suitability and quality of adhesives for load-bearing timber structures;

c) for determining if the adhesive is capable of withstanding stresses due to wood shrinkage without

unacceptable loss of strength.

This test is intended primarily to obtain performance data for the classification of adhesives for load-

bearing timber structures according to their suitability for use in defined climatic environments. This test

is carried out on Norway spruce (Picea abies L.).

This method is not intended for use to provide numerical design data and does not necessarily represent

the performance of the bonded member in service.
2 Normative references

The following documents are referred to in the text in such a way that some or all of their content

constitutes requirements 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 301, Adhesives, phenolic and aminoplastic, for load-bearing timber structures - Classification and

performance requirements

EN 13183-1, Moisture content of a piece of sawn timber - Part 1: Determination by oven dry method

ISO 5893, Rubber and plastics test equipment - Tensile, flexural and compression types (constant rate of

traverse) - Specification

ISO 6344-2, Coated abrasives - Grain size analysis - Part 2: Determination of grain size distribution of

macrogrits P12 to P220
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

— ISO Online brows
...

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