National foreword

This British Standard is the UK implementation of EN 12812:2008. It supersedes BS EN 12812:2004 which is withdrawn.

The UK participation in its preparation was entrusted to Technical Committee 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.

BS EN 12812:2008 specifies performance requirements for the design of false work 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 parallel with this standard and provides recommendations on the design of false work, without definition of classes or physical parameters and using permissible stress methods, is re commended by Technical Committee B/514 as a suitable method for the structural design of Class A false work, as defined in BS EN 12812:2008.

The 'Bragg Report', published in 1975 by the Advisory Committee on False work, 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-order analysis. Technical Committee B/514 advises that the application of this force has made a significant contribution to the safe use of false work 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 management of work on site. The recommendations of the 'Bragg Report' in respect of the false work coordinator have not been included in it.

BS 5975 includes procedural controls for all temporary works, including false work, for the design, independent checking of the design, and for the successful management 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 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 should be read with caution.

A list of organizations represented on this committee can be obtained on request to its secretary.

This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application.

Compliance with a British Standard cannot confer immunity from legal obligations.

This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 January 2011.

This 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 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 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 Management Centre has the same status as the official versions.

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

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 by 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 for 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 standards 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, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom.

Introduction

Most false work is used:

to carry the loads due to freshly poured concrete for permanent structures until these structures have reached a sufficient load bearing capacity;
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 European Standard gives performance requirements for specifying and using false work and gives methods to design false work to meet those requirements. Clause 9 provides design methods. It also gives simplified design methods for false work made of tubes and fittings. The information on structural design is 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 and other documents.

1 Scope

This European Standard specifies performance requirements and limit state design methods for two design classes of false work.

It sets out the rules that have to be taken into account to produce a safe false work structure.

It also provides information for false work which is required to support a "permanent structure", or where the design or supply of false work has to be commissioned.

This European Standard also gives information on foundations.

This European Standard does not specify requirements for formwork, although formwork may be a part of the false work 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 timber formwork beams conforming to EN 13377 and props conforming to EN 1065.

2 Normative references

3 Terms and definitions

4 Design classes

4.1 General

4.2 Design class A

4.3 Design class B

5 Materials

5.1 General

5.2 Basic requirements for materials

5.3 Weldability

6 Brief

7 Design requirements

7.1 General

7.2 Thickness of material

7.3 Connections

7.4 Flexibility of prefabricated support towers

7.5 Foundation

7.6 Towers providing support

8 Actions

8.1 General

8.2 Direct actions

8.3 Indirect actions

8.4 Other actions “Q₉”

8.5 Load combinations

9 Structural design for classes B1 and B2

9.1 Technical documentation

9.2 Structural design

9.3 Imperfections and boundary conditions

9.4 Calculation of internal forces

9.5 Characteristic values of resistance and friction values

Bibliography

BS EN 12812:2008

Falsework. Performance requirements and general design

Current

Published:

31 Jan 2011