1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS EN 12812:2008Falsework Performance requirements and general designBS EN 12812:2008 BRITISH STANDARDA list of organizations represented on this committee can beobtained on requ
2、est to its secretary.This publication does not purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. BSI 2011 ISBN 978 0 580 60505 5 ICS 91.220 Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Stand
3、ard was published under the authority of theStandards Policy and Strategy Committee on 31 January 2011.Amendments issued since publicationDateT e x t a f f e c t e dNational forewordThis British Standard is the UK implementation of EN 12812:2008. It supersedes BS EN 12812:2004 which is withdrawn.The
4、 UK participation in its preparation was entrusted to TechnicalCommittee B/514, Access and support equipment.The design methodology within BS EN 12812:2008 is significantly different from that in BS 5975. Technical Committee B/514 advises that caution should be taken when applying BS EN 12812:2008.B
5、S EN 12812:2008 specifies performance requirements for the design of falsework in accordance with one of three classes: A, B1 and B2. Limit state design methods are specified for design Classes B1 and B2. It does not provide guidance for the structural design of Class A. BS 5975, which exists in par
6、allel with this standard and provides recommendations on the design of falsework, without definition of classes or physical parameters and using permissible stress methods, is recommended by Technical Committee B/514 as a suitable method for the structural design of Class A falsework, as defined in
7、BS EN 12812:2008.The Bragg Report, published in 1975 by the Advisory Committee on Falsework, first introduced a minimum lateral stability force. This force was subsequently incorporated, as a minimum horizontal disturbing force of 2.5 % of the applied vertical load in BS 5975, assuming first-this fo
8、rce has made a significant contribution to the safe use of falsework in the UK since its introduction. Technical Committee B/514 also advises that BS EN 12812:2008 does not recommend a minimum horizontal force.BS EN 12812:2008 does not provide guidance on procedures necessary for the successful mana
9、gement of work on site. The recommendations of the Bragg Report in respect of the falsework coordinator have not been included in it. BS 5975 includes procedural controls for all temporary works, including falsework, for the design, independent checking of the design, and for the successful manageme
10、nt of work on site, including the appointment of a temporary works coordinator. Technical Committee B/514 reaffirms the importance of these controls.This standard contains a National Annex NA that provides informative guidance on its application. It should be noted that there are a number of textual
11、 and numerical differences between the 2004 and 2008 editions; only those that are considered to be material are commented on in the National Annex NA. It is therefore not a comprehensive listing of all of the differences. Further, the UK committee advises that the symbols used in this standard shou
12、ld be read with caution.order analysis. Technical Committee B/514 advises that the application of EUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN 12812July 2008ICS 91.220 Supersedes EN 12812:2004 English VersionFalsework - Performance requirements and general designEtaiements - Exigences de perfor
13、mance et mthodes deconception et calculsTraggerste - Anforderungen, Bemessung und EntwurfThis European Standard was approved by CEN on 7 June 2008.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a
14、 national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the CEN Management Centre or to any CEN member.This European Standard exists in three official versions (English, French, German). A version
15、in any other language made by translationunder the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as theofficial versions.CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark,
16、Estonia, Finland,France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROP
17、ISCHES KOMITEE FR NORMUNGManagement Centre: rue de Stassart, 36 B-1050 Brussels 2008 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 12812:2008: EEN 12812:2008 (E) 2 Contents Page Foreword. 3 Introduction 4 1 Scope . 5 2 Normative re
18、ferences . 5 3 Terms and definitions. 6 4 Design classes 7 4.1 General. 7 4.2 Design class A 7 4.3 Design class B 7 5 Materials 8 5.1 General. 8 5.2 Basic requirements for materials 8 5.3 Weldability . 8 6 Brief 8 7 Design requirements 8 7.1 General. 8 7.2 Thickness of material . 9 7.3 Connections 9
19、 7.4 Flexibility of prefabricated support towers 9 7.5 Foundation 10 7.6 Towers providing support . 12 8 Actions. 13 8.1 General. 13 8.2 Direct actions 13 8.3 Indirect actions . 17 8.4 Other actions “Q9” 17 8.5 Load combinations. 17 9 Structural design for classes B1 and B2 18 9.1 Technical document
20、ation 18 9.2 Structural design 20 9.3 Imperfections and boundary conditions 23 9.4 Calculation of internal forces 30 9.5 Characteristic values of resistance and friction values . 37 Annex A (informative) Relation with site activities . 40 Annex B (informative) . 41 Bibliography . 42 BS EN 12812:2008
21、EN 12812:2008 (E) 3 Foreword This document (EN 12812:2008) has been prepared by Technical Committee CEN/TC 53 “Temporary works equipment”, the secretariat of which is held by DIN. This European Standard shall be given the status of a national standard, either by publication of an identical text or b
22、y endorsement, at the latest by January 2009, and conflicting national standards shall be withdrawn at the latest by January 2009. 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 not be held responsible fo
23、r identifying any or all such patent rights. This document supersedes EN 12812:2004. This European Standard is one of a package of standards that includes also EN 12810-1, EN 12810-2, EN 12811-1, EN 12811-2, EN 12811-3, EN 12813. According to the CEN/CENELEC Internal Regulations, the national standa
24、rds organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Por
25、tugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. BS EN 12812:2008EN 12812:2008 (E) 4 Introduction Most falsework is used: to carry the loads due to freshly poured concrete for permanent structures until these structures have reached a sufficient load bearing cap
26、acity; to absorb the loads from structural members, plant and equipment which arise during the erection, maintenance, alteration or removal of buildings or other structures; additionally, to provide support for the temporary storage of building materials, structural members and equipment. This Europ
27、ean Standard gives performance requirements for specifying and using falsework and gives methods to design falsework to meet those requirements. Clause 9 provides design methods. It also gives simplified design methods for falsework made of tubes and fittings. The information on structural design is
28、 supplementary to the relevant Structural Eurocodes. The standard describes different design classes. This allows the designer to choose between more or less complex design methods, while achieving the same level of structural safety. Provision for specific safety matters is dealt with in EN 12811-1
29、 and other documents. BS EN 12812:2008EN 12812:2008 (E) 5 1 Scope This European Standard specifies performance requirements and limit state design methods for two design classes of falsework. It sets out the rules that have to be taken into account to produce a safe falsework structure. It also prov
30、ides information for falsework which is required to support a “permanent structure“, or where the design or supply of falsework has to be commissioned. This European Standard also gives information on foundations. This European Standard does not specify requirements for formwork, although formwork m
31、ay be a part of the falsework construction. Nor does it provide information on access and working scaffolds, which is given in EN 12811-1. This European Standard does not provide information about site activities. It does not provide information about the use of some standardized products, including
32、 timber formwork beams conforming to EN 13377 and props conforming to EN 1065. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the ref
33、erenced document (including any amendments) applies. EN 74-1, Couplers, spigot pins and baseplates for use in falsework and scaffolds Part 1: Couplers for tubes Requirements and test procedures prEN 74-2, Couplers, spigot pins and baseplates for use in falsework and scaffolds Part 2: Special coupler
34、s Requirements and test procedures EN 74-3, Couplers, spigot pins and baseplates for use in falsework and scaffolds Part 3: Plain base plates and spigot pins Requirements and test procedures EN 1065:1998, Adjustable telescopic steel props Product specifications, design and assessment by calculation
35、and tests EN 1090-2, Execution of steel structures and aluminium structures - Part 2: Technical requirements for steel structures EN 1090-3, Execution of steel structures and aluminium structures - Part 3: Technical requirements for aluminium structures EN 1990, Eurocode Basis of structural design E
36、N 1991 (all parts), Eurocode 1 Actions on structures EN 1993-1-1:2005, Eurocode 3: Design of steel structures - Part 1-1: General rules and rules for buildings EN 1997 (all parts), Eurocode 7 Geotechnical design EN 1998 (all parts), Eurocode 8 Design of structures for earthquake resistance EN 1999 (
37、all parts), Eurocode 9 Design of aluminium structures BS EN 12812:2008EN 12812:2008 (E) 6 EN 12810-1:2003, Facade scaffolds made of prefabricated components Part 1: Product specifications EN 12811-1:2003, Temporary works equipment Part 1: Scaffolds Performance requirements and general design EN 1281
38、1-3, Temporary works equipment Part 3: Load testing EN 12813, Temporary works equipment - Load bearing towers of prefabricated components - Particular methods of structural design EN 13377, Prefabricated timber formwork beams Requirements, classification and assessment 3 Terms and definitions For th
39、e purposes of this document, the terms and definitions in EN 1993-1-1:2005 and the following apply. 3.1 brace component connecting two points of a structure to help stiffen it 3.2 design class class that defines the extent of design for falsework 3.3 falsework temporary support for a part of a struc
40、ture while it is not self-supporting and for associated service loads 3.4 formwork part of temporary works used to give the required shape and support to in-situ concrete 3.5 foundation sub-structure needed to transmit loads into the ground 3.6 kentledge material placed on a structure to provide sta
41、bility by the action of its dead weight 3.7 imperfections initial out of straightness (bow imperfection) or out of verticality (sway imperfection) of a structural component or of the structure used for calculations NOTE 1 A bow imperfection can occur both in an individual member and in the complete
42、tower or modular beam assembly. It arises because the member is not straight, is manufactured not straight or members are assembled out of alignment. NOTE 2 These are the values for design purposes and may be more than the erection tolerance. 3.8 node theoretical intersection point of members BS EN
43、12812:2008EN 12812:2008 (E) 7 3.9 sway angular deflection of a column or other structure caused by the application of load 4 Design classes 4.1 General The design shall be in accordance with one of the classes: A or B. Class B has two subclasses, B1 and B2, see 4.3 where the designer has to decide w
44、hich subclass shall be applied. 4.2 Design class A NOTE A Class A falsework is one which follows established good practice which may be deemed to satisfy the design requirements. Class A covers falsework for simple constructions such as in situ slabs and beams. Class A shall only be adopted where: a
45、) slabs have a cross-sectional area not exceeding 0,3 m2per metre width of slab; b) beams have a cross-sectional area not exceeding 0,5 m2; c) the clear span of beams and slabs does not exceed 6,0 m; d) the height to the underside of the permanent structure does not exceed 3,5 m. The design for clas
46、s A falsework shall be in accordance with the descriptive requirements in Clauses 5 and 7. 4.3 Design class B Class B falsework is one for which a complete structural design is undertaken. Class B falsework is required to be designed in accordance with the relevant Eurocodes. There are separate addi
47、tional provisions in this code for Classes B1 and B2 that are detailed below. Class B2 uses a simpler design method than Class B1 to achieve the same level of safety. 4.3.1 Class B1 The design shall be in accordance with the relevant Eurocodes (EN 1990, EN 1991 to EN 1999) and additionally with 9.1.
48、1, 9.1.2.1, 9.1.3, 9.3.3 and 9.4.1 of the present standard. NOTE It is assumed that the erection will be carried out to the level of workmanship appropriate for permanent construction, see EN 1090-2 and EN 1090-3 for metal structures. 4.3.2 Class B2 The design shall be in accordance with Clauses 5,
49、6, 7, 8 and 9, with the exception of 9.1.2.1, 9.3.3, 9.4.1, and with the relevant Eurocodes (EN 1991, EN 1990 to EN 1999). Where there is a conflict, the provisions of the present standard shall take precedence. NOTE Attention is drawn to the simplified methods given in 9.3 and 9.4 and to the requirements for drawings and other documentation given in 9.1.2. BS EN 12812:2008EN 12812:2008 (E) 8 5 Materials 5.1 General Only materials that have established properties and that are known to be suitable for the intended use shall be used
