1、BRITISH STANDARD Prefabricated timber formwork beams - Requirements, classification and assessment The European Standard EN 13377:2002 has the status of a British Standard ICs 91.220 BS EN 13377:2002 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW BS EN 13377:ZOOZ Amd. No. ISB
2、N O 580 40939 2 National foreword Date Comments This British Standard is the official English language version of EN 13377:2002. The UK participation in its preparation was entrusted by Technical Committee B/514, Access and support equipment, to Subcommittee B/514/26, Falsework, which has the respon
3、sibility to: - - aid enquirers to understand the text; present to the responsible internationaUEuropean committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. -
4、 A list of organizations represented on this subcommittee can be obtained on request to its secretary. Attention is drawn to National Annex NA (informative) which contains additional information and explanations for UK users. Cross-references The British Standards which implement international or Eu
5、ropean publications referred to in this document may be found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online. This publication does not purport to include
6、 all the necessary provisions of a contract. Users are responsible for its correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. This British Standard, having been prepared under the direction of the Building and civil Enpineering Sector p
7、olicv Summary of pages This document comprises a front cover, an inside front cover, the EN title page, pages 2 to 28, an inside back cover and a back cover. - - and was published under the authority ofthe Standards policv and The BSI copyright date displayed in this document indicates when the docu
8、ment was last issued. Strategy Committee on 5 December 2002 Amendments issued since publication O BSI 5 December 2002 EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 13377 August 2002 ICs 91.220 English version Prefabricated timber formwork beams - Requirements, classification and assessment Po
9、utrelles de coffrage prfabriques en bois - Exigences, classification et valuation Industriell gefertigte Schalungstrger aus Holz - Anforderungen, Klassifizierung und Nachweis This European Standard was approved by CEN on 29 May 2002 CEN members are bound to comply with the CENKENELEC Internal Regula
10、tions 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 Management Centre or to any CEN member. This Europ
11、ean 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 Management Centre has the same status as the official versions. CEN members are the nationa
12、l standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION EUROPISCHES KOMITEE FR NORMUNG COMIT EUR
13、OPEN DE NORMALISATION Management Centre: rue de Stassart, 36 B-1050 Brussels O 2002 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 13377:2002 E EN 13377:2002 (E) Contents page Foreword 3 Introduction . 4 1 Scope 4 2 Normative refe
14、rences 4 3 Terms. definitions and symbols . 5 4 Classification 8 5 Performance requirements . 8 6 Prototype assessment . 11 7 Evaluation of conformity . 11 8 Ongoing production inspection . 12 9 Marking . 12 10 Instructions for use . 12 Annex A (normative) Test and calculation methods to establish s
15、tructural parameters . 13 Annex B (normative) Statistical analysis of test results for the calculation of the characteristic value 18 Annex C (normative) Minimum requirements for production control 19 Annex D (normative) Test procedures for beams with webs conforming to 5.2.2.c) 21 Annex E (informat
16、ive) Values for use in calculation for site use 24 Annex F (informative) Ongoing production inspection 26 Bibliography 27 2 EN 13377:2002 (E) Foreword This document EN 13377:2002 has been prepared by Technical Committee CEN/TC 53 “Temporary works equipment“, the secretariat of which is held by DIN.
17、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 February 2003, and conflicting national standards shall be withdrawn at the latest by February 2003. The annexes A, B, C and D are normative, the an
18、nexes E and F are informative. According to the CENKENELEC Internal Regulations, the national 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, Luxemb
19、ourg, Malta, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom. 3 EN 13377:2002 (E) Introduction This European Standard is a product standard primarily for use in the field of falsework and formwork. Formwork beams should be made so that the properties specified in cla
20、use 5 are retained under site conditions such as exposure to water, water vapour and cement. Whilst this European Standard deals with the two most common types of prefabricated timber formwork beams in use it is not intended to prevent development of other types of formwork beams made of timber and
21、wood based materials. Research and development in the field of panel materials is continuous. Even if formwork beams are made with materials which do not conform with this European Standard, the principles of this European Standard should be considered in the design and assessment of such beams. To
22、obtain test results and their statistical evaluation annexes A and B respectively can be used. The values for strength and stiffness given in Tables 1 and 2 have been established from experience. To use these values, the partial safety factor for actions, E, should be taken into account as well as t
23、he partial safety factor for the material, I/.I, and modification factor, kmod, for timber, (see ENV 1995-1-1). Annex E gives some guidance. For more information on timber see the Bibliography in annex F. 1 Scope This European Standard specifies classification, requirements and assessment procedures
24、 for prefabricated timber formwork beams. It also gives information on production control requirements. Prefabricated timber formwork beams are intended for use in falsework and formwork and to be loaded in the direction of the beam depth. They are of glued I-shaped construction consisting of two id
25、entical flange members of solid timber connected by a single web of wood based material with beam depths of 160 mm, 200 mm and 240 mm, or connected by or a lattice of solid timber members with a beam depth of 240 mm beam depth. 2 Normative references This European Standard incorporates by dated or u
26、ndated reference, provisions from other publications. These normative references are cited at the appropriate places in the text, and the publications are listed hereafter. For dated references, subsequent amendments to or revisions of any of these publications apply to this European Standard only w
27、hen incorporated in it by amendment or revision. For undated references the latest edition of the publication referred to applies (including amendments). EN 301, Adhesives, phenolic and aminoplastic for load bearing timber structures - Classification and performance requirements. EN 31 O, Wood-based
28、 panels - Determination of modulus of elasticity in bending and of bending strength. EN 31 7, Particleboards and fibreboards - Determination of swelling in thickness after immersion in water. EN 31 9, Particleboards and fibreboards - Determination of tensile strength perpendicular to the plane of th
29、e board. EN 323, Wood based panels - Determination of density. 4 EN 13377:2002 (E) EN 338, Structural timber - Strength classes. EN 385: 1 995, Finger jointed structural timber - Performance requirements and minimum production requirements. EN 408, Timber structures -Solid timber and glued laminated
30、 timber - Determinations of some physical and mechanical properties. EN 51 8, Structural timber - Grading - Requirements for visual strength grading standards. EN 51 9, Structural timber - Grading - Requirements for machine strength graded timber and grading machines. EN 636-3, Plywood - Specificati
31、ons - Part 3: Requirements for plywood for use in exterior conditions. ENV 1995-1-1 :I 993, EUROCODE 5: Design of timber structures - Part 1-1: General rules and rules for buildings. EN 131 83-2, Moisture content of a piece of sawn timber - Part 2: Estimation by electrical resistance method. prEN 13
32、353, Solid-wood-panels - Requirements. prEN 13354, Solid-wood-panels - Bonding quality - Test method. 3 Terms, definitions and symbols 3.1 Terms and definitions For the application of this European Standard, the following terms and definitions apply. 3.1 .I formwork beam beam in formwork constructio
33、n and loaded in the direction of the beam depth 3.1.2 timber formwork beam glued prefabricated I-shaped beam consisting of two identical flange members of solid timber connected by a web of wood based panel material or a lattice of solid timber members 3.1.3 panel web beam timber formwork beam in wh
34、ich the web is made of a wood based panel material (see Figure la) 3.1.4 lattice web beam timber formwork beam made with lattice struts (see Figure 1 b). 3.1.5 lattice strut member, positioned diagonally or at right angles to the flange, which connects two parallel flange members (see Figure 1 b) 5
35、EN 13377:2002 (E) Key H Depth of beam b Flange width h Depth (thickness) of flange t Thickness of web Key 1 Flange 2 Panelweb 3 Vertical strut 4 Diagonal strut a) Panel web beam (type P) b) Lattice web beam (type L) Figure 1 - Timber formwork beams General construction and symbols used for the dimen
36、sions 3.2 Symbols The principal symbols used in this standard are listed below: 6 EN 13377:2002 (E) Number 1 2 Symbol Denomination Unit U module of the lattice web beam mm b flange width mm 3 4 5 I EI I bending stiffness e E modulus of elasticity kN/mm2 distance of proportion at load positions I kNm
37、2 6 7 F action kN H depth of beam mm 8 9 10 II I k, I statistical factor 1 h depth (thickness) of flange mm I second moment of area m m4 kmod modification factor 12 I L Ispanof beam 13 14 15 16 Im M bending resistance kNm n number of specimens R resistance kN/mm2 S standard deviation 17 18 19 20 t t
38、hickness of web mm V shear resistance kN W section modulus mm3 Y mean value 21 22 23 I I partial safety factor for material yi single value partial safety factor for actions 7 EN 13377:2002 (E) 1 4 Classification This standard specifies types of beam; the classification is based on: - the web constr
39、uction: Type P for a panel web beam; Type L for a lattice web beam; - the overall depth, H: the two digits in the identification symbols represent the depth in centimetres. The nominal load bearing and rigidity properties for each class are listed in Tables 1 and 2. For classification see Tables 1 a
40、nd 2. The identification symbols are given in column 1 of Tables 1 and 2. 2 3 4 5 6 7 Table 1 - Classification, dimensions and structural properties of panel web beams beam depth minimum flange width Class I bimml EI vi, MI I kN I :G I kNm kNm2 1 Class L24 PI6 I 160 I 65 I 200 I 18,4 I 36,8 I 5.9 2
41、3 4 5 6 7 8 9 Rb,n,k Rb,m,l MILI Mm,i kNI kNI kNmI kNmI minimum beam fiange EI vi, depth width b kNm2 kNI supported supported supported in between supported at nodes in between nodes mml at nodes nodes mml 240 80 800 28,2 60,7 43,4 15,2 8,7 P20 I 200 I 80 I 450 I 23,9 I 47,8 I 10.9 P24 I 240 I 80 I
42、700 I 28,2 I 56,4 I 14.1 NOTE 1 NOTE 2 For explanation of symbols, see 3.2. For calculation of “safe working loads“, see annex E. To obtain the required bearing area, the lateral compression strength for the strength class C 24 with 5,3 N/mm2 in accordance with EN 338:1995 shall be used. 5 Performan
43、ce requirements 5.1 General Beams shall conform to the requirements of this clause according to their class. Conformity with the requirements shall be verified, see clauses 6 and 7, and manufacturing shall be subject to production control, see clause 8 and annex C. 8 EN 13377:2002 (E) All requiremen
44、ts should be met with a moisture content of solid timber members of (12 f 2) % (manufacturing target moisture content). 5.2 Material and assembly requirements 5.2.1 Members of solid timber shall at least conform to strength class C 24 of EN 338. Solid timber components -strength class NOTE exceed 20
45、 %. It is recommended that the growth ring width is less than 4 mm and the amount of compression wood does not 5.2.2 Wood based panel components The web shall be made of one of the following materials: a) b) plywood conforming to EN 636-3; solid wood panels for use in exterior conditions conforming
46、to prEN 13353; c) any other wood based material, which conforms after passing the wet-dry-cyclic test (see annex D) with the subsequent requirements: i) tension strength perpendicular to the plane determined in accordance with EN 319 shall not be less than 0,l N/mm2 (see D.3.1); and i) irreversible
47、swelling shall not exceed 20 % (see D.3.2). The following properties of this wood based material shall be made available: - density established in accordance with EN 323; - bending strength established in accordance with EN 310; - thickness swelling established in accordance with EN 31 7; - internal
48、 bond established in accordance with EN 31 9 The established properties shall be used as requirements for production control (see annex C). 5.2.3 Shear strength of the glue line in beam sections with webs conforming to 5.2.2 After applying the wet-dry cyclic testing procedure given in annex D, the m
49、ean value of the shear strength of beam sections shall be at least 9 kN (see D.4.6). 5.2.4 Glued finger joints Glued finger joints in flanges shall conform to EN 385. 5.2.5 Glue Glue shall fulfil the requirements of type I of EN 301. 9 EN 13377:2002 (E) 5.3 Dimensions 5.3.1 Principal dimensions The length of the beam shall conform to the manufacturers declared dimension within a tolerance of 10 mm. The beam depth, H, shall conform to the data in Tables 1 and 2 within a limit deviation of f 1 % or f 2 mm, whichever is the smaller. The flange width, b, shall conf
