DIN EN 384-2016 Structural timber - Determination of characteristic values of mechanical properties and density German version EN 384 2016《木材结构 机械性能和密度特征值的测定 德文版本EN 384-2016》.pdf

1、December 2016 English price group 12No part of this translation may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).ICS 79.040!%V5“2595118www.din.deDIN

2、 EN 384Structural timber Determination of characteristic values of mechanical properties and density;English version EN 384:2016,English translation of DIN EN 384:2016-12Bauholz fr tragende Zwecke Bestimmung charakteristischer Werte fr mechanische Eigenschaften und Rohdichte;Englische Fassung EN 384

3、:2016,Englische bersetzung von DIN EN 384:2016-12Bois de structure Dtermination des valeurs caractristiques des proprits mcaniques et de la masse volumique;Version anglaise EN 384:2016,Traduction anglaise de DIN EN 384:2016-12SupersedesDIN EN 384:201008www.beuth.deDTranslation by DIN-Sprachendienst.

4、In case of doubt, the German-language original shall be considered authoritative.Document comprises 21 pages 11.16 DIN EN 384:2016-122 A comma is used as the decimal marker. National foreword This document (EN 384:2016) has been prepared by Technical Committee CEN/TC 124 “Timber structures” (Secreta

5、riat: AFNOR, France). The responsible German body involved in its preparation was DIN-Normenausschuss Bauwesen (DIN Standards Committee Building and Civil Engineering), Working Committee NA 005-04-01 AA Holzbau (SpA zu CEN/TC 124, CEN/TC 250/SC 5, ISO/TC 165). Amendments This standard differs from D

6、IN EN 384:2010-08 as follows: a) the terms and definitions have been revised; b) the adjustments of test results to the reference moisture content are now presented as equations; c) the equations for determining other properties from properties derived by testing have been amended; d) as regards the

7、 determination of the 5 %-percentiles, the standard has been adapted to the revised version of EN 14358; e) the procedure for verification of a lot has been transferred to EN 14358. Previous editions DIN EN 384: 1996-07, 2004-05, 2010-08 EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 384 Augus

8、t 2016 ICS 79.040 Supersedes EN 384:2010English Version Structural timber - Determination of characteristic values of mechanical properties and density Bois de structure - Dtermination des valeurs caractristiques des proprits mcaniques et de la masse volumique Bauholz fr tragende Zwecke - Bestimmung

9、 charakteristischer Werte fr mechanische Eigenschaften und Rohdichte This European Standard was approved by CEN on 30 January 2016. 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 stan

10、dard 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 a

11、ny 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 Rep

12、ublic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey andUnited Kingdom. EUROPEAN

13、 COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management 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 384:2016 EEN 384:201

14、6 (E) 2 Contents Page European foreword . 3 Introduction 4 1 Scope 5 2 Normative references 5 3 Terms and definitions . 5 4 Symbols and abbreviations . 6 5 Mechanical properties determined from full-size specimens 8 5.1 Sampling . 8 5.2 Testing . 8 5.3 Reference conditions . 8 5.3.1 Moisture content

15、 . 8 5.3.2 Bending strength . 8 5.3.3 Tension strength . 8 5.3.4 Density 8 5.4 Adjustment factors . 9 5.4.1 General 9 5.4.2 Moisture content . 9 5.4.3 Timber size and test length . 9 5.4.4 Modulus of elasticity . 10 5.4.5 Other adjustments . 10 5.5 Analysis of data . 10 5.5.1 Sub-sample analysis 10

16、5.5.2 Characteristic values . 11 6 Bending strength and modulus of elasticity determined from small, clear hardwood specimens . 13 7 Other mechanical properties for hardwoods and softwoods 13 8 Report . 15 Annex A (normative) Requirements for reports for visual grading assignment . 16 Bibliography .

17、 19 DIN EN 384:2016-12 EN 384:2016 (E) 3 European foreword This document (EN 384:2016) has been prepared by Technical Committee CEN/TC 124 “Timber structures”, the secretariat of which is held by AFNOR. This European Standard shall be given the status of a national standard, either by publication of

18、 an identical text or by endorsement, at the latest by February 2017, and conflicting national standards shall be withdrawn at the latest by February 2017. 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 n

19、ot be held responsible for identifying any or all such patent rights. This document supersedes EN 384:2010. Compared to EN 384:2010, the following modifications have been made: the definitions have been revised; the adjustments of test results to the reference moisture content are presented as equat

20、ions; the equations for determining other properties from properties derived by testing have been changed; regarding the determination of 5 %-percentiles the standard has been adopted to the revised EN 14358; the procedure for verification of a lot has been transferred to EN 14358. According to the

21、CEN/CENELEC 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, Hun

22、gary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. DIN EN 384:2016-12 EN 384:2016 (E) 4 Introduction Structural design codes can only function effectively

23、if standard methods of determining the mechanical and physical properties exist. The aim of the procedures given in this standard is to derive characteristic values that are comparable in terms of the populations they represent. The standard permits the use of as much existing test data as possible

24、from various sampling and testing techniques. Where methods are given to permit characteristic values to be determined from a less than ideal amount of structural size test data, reduction factors to reflect a lower degree of confidence are employed. DIN EN 384:2016-12EN 384:2016 (E) 5 1 Scope This

25、European Standard gives a method for determining characteristic values of mechanical properties and density, for defined populations of visual grades and/or strength classes of machine graded structural timber. Additionally it covers the stages of sampling, testing, analysis and presentation of the

26、data. The standard provides methods to derive strength, stiffness and density properties for structural timber from tests with defect-free specimen. The values determined in accordance with this standard for mechanical properties and density are suitable for assigning grades and species to the stren

27、gth classes of EN 338. NOTE 1 For assigning grades and species to the strength classes in EN 338 only three properties, i.e. bending or tension strength, modulus of elasticity parallel to grain in bending or tension and density need to be determined from test data, other properties can be calculated

28、 according to Table 2. NOTE 2 EN 1912 gives examples of established visual grades assigned to strength classes. 2 Normative references The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the e

29、dition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 338, Structural timber Strength classes EN 408, Timber structures Structural timber and glued laminated timber Determination of some physical and mechanical properties E

30、N 13183-2, Moisture content of a piece of sawn timber Part 2: Estimation by electrical resistance method EN 13183-3, Moisture content of a piece of sawn timber Part 3: Estimation by capacitance method EN 14081-1:2016, Timber structures Strength graded structural timber with rectangular cross section

31、 Part 1: General requirements EN 14081-2, Timber structures Strength graded structural timber with rectangular cross section Part 2: Machine grading; additional requirements for initial type testing EN 14081-3, Timber structures Strength graded structural timber with rectangular cross section Part 3

32、: Machine grading; additional requirements for factory production control EN 14358:2016, Timber structures Calculation and verification of characteristic values 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 characteristic value representati

33、ve value of a material property used for design, which is based either on 5-percentile values (e.g. strength properties and density) or mean values (e.g. modulus of elasticity) DIN EN 384:2016-12 EN 384:2016 (E) 6 3.2 p-percentile value for which the probability of getting lower values is p % 3.3 po

34、pulation timber for which the characteristic values are relevant 3.4 timber source identifiable geographical origin of a species or species combination from which timber is, or is intended to be, strength graded 3.5 sample a number of ungraded specimens of one timber species or species combination,

35、one source, with sizes and quality representative of the timber population (see 5.1) 3.6 sub-sample part of one or more samples consisting of specimens of one grade 3.7 small clear test test to determine mechanical properties of small defect-free specimens 3.8 specimen piece of timber from which the

36、 test piece is taken 3.9 thickness lesser dimension perpendicular to the longitudinal axis of a piece of timber 3.10 width larger dimension perpendicular to the longitudinal axis of a piece of timber 3.11 depth in the case of bending, cross-sectional dimension parallel to the direction of loading; i

37、n the case of tension, the width 4 Symbols and abbreviations afdistance between the inner load points of the bending test (in mm) E0modulus of elasticity parallel to grain (in N/mm2) E0,meanmean characteristic value of modulus of elasticity parallel to grain (in N/mm2) E0,k 5-percentile characterist

38、ic value of modulus of elasticity parallel to grain (in N/mm2) E90,meanmean characteristic value of modulus of elasticity perpendicular to grain (in N/mm2) E i mean modulus of elasticity for one sub-sample (in N/mm2) DIN EN 384:2016-12 EN 384:2016 (E) 7 Ei,min lowest mean modulus of elasticity of al

39、l sub-samples (in N/mm2) Em,globalglobal modulus of elasticity in bending (in N/mm2) Em,locallocal modulus of elasticity in bending (in N/mm2) f strength property fc,0,k5- percentile characteristic value of compression strength parallel to grain (in N/mm2) fc,90,k5- percentile characteristic value o

40、f compression strength perpendicular to grain (in N/mm2) fk5- percentile characteristic value of strength (in N/mm2) fm,k5- percentile characteristic value of bending strength (in N/mm2) ft,0,k5- percentile characteristic value of tension strength parallel to grain (in N/mm2) ft,90,k5- percentile ch

41、aracteristic value of tension strength perpendicular to grain (in N/mm2) f05,i5-percentile value for each sub-sample (in N/mm2) f05,i,minlowest 5-percentile value of all sub-samples (in N/mm2) fv,k5- percentile characteristic value of shear strength (in N/mm2) Gmeanmean characteristic value of shear

42、 modulus (in N/mm2) h depth (in mm) khfactor for adjusting f when h is not 150 mm klfactor for adjusting f when test span is not 18 h knfactor to adjust for the number of sub-samples kvfactor to allow for the lower variability of f05values between sub-samples for machine grades in comparison with vi

43、sual grades span (in mm) eteffective length for the test (in mm) n total number of specimens ninumber of specimens in a sub-sample ns number of sub-samples u moisture content (in %) u ref reference moisture content, normally at 12 % density (in kg/m3) mean mean density (in kg/m3) kcharacteristic den

44、sity (5-percentile) (in kg/m3) 05,i5-percentile density for a sub-sample (in kg/m3) 05,i,minlowest 5-percentile density of all sub-samples (in kg/m3) DIN EN 384:2016-12EN 384:2016 (E) 8 5 Mechanical properties determined from full-size specimens 5.1 Sampling The sampling shall be representative of t

45、he population. Any known or suspected difference in the mechanical properties of the population due to e.g. sawmills, tree size, countries or silviculture shall be represented within the sampling by a similar proportion to their frequency in the population. This shall be the major influence in deter

46、mining the number and size of samples. Samples shall be selected from one source of timber and shall be graded visually or by machine to sub-samples according to the requirements given in EN 14081-1. For visual grading, each sub-sample shall consist of at least 40 specimens and be of one source. For

47、 bending and tension parallel to grain tests, specimens shall have a sufficient length so that critical defects can be located in the critical test zone (see 5.2). A length of at least 30 times the depth or 3.6 m whichever is the lesser meets this requirement. For the determination of strengths perp

48、endicular to the grain and shear strength clear specimens shall be sampled. 5.2 Testing Testing shall be carried out in accordance with EN 408 for strength, modulus of elasticity, density and moisture content. For bending parallel to grain, tension parallel to grain or modulus of elasticity, a criti

49、cal section shall be selected in each piece of timber. This section is the position at which failure is expected to occur and therefore determines the grade for that piece. For bending the tension edge shall be selected at random. Whenever possible the critical section shall be placed inside the inner load points in a bending test or between the jaws in a tension test (centrally if possible). If this is not possible, the second most critical