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BS5975:2019Overview of Procedures

25 July 2019

Peter F. PallettFrank MarplesMember BSI committee

since 1977Chairman BSI committee

Member since 1998

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BS 5975:2019 Code of practice for temporary works procedures and the permissible stress design

of falsework

Published 30th May 2019

First Published 1982Second Edition 1996Third Edition 2008

Amended 2011Fourth Edition 2019 Only Section One &

Section Two on

Procedures are updated

248 pages£340.20{ £378 full price }

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BS 5975:2019 - Presentation Topics

Section One Clause 5 Overview and Training by Peter( Including contractual interfaces )

Section Two Clause 6 Procedural Control( Including new Implementation Risk table)

Clause 7 ClientsClause 8 DesignersClause 9 Contractors (PC & Managing)Clause 10 Suppliers/manufacturers

Clause 11 Temporary Works Co-ordinator( Changes to Duties )

Clause 12 Temporary Works Supervisor

Clause 13 Design of Temporary Works( Stability, LS & PS safety factors, categories check )

Introduction & Foreword by Frank

Clause 14 Site considerations

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BS 5975:2019 What’s Changed since 2008/2011 ?

1. CDM Regulations in 2015

(a) Introduced Principal Designers (PD)and Principal Contractors (PC)

(b) Detailed roles and duties

2. More specialist temporary works contractorstaking on managing temporary works and subsequent reduction in contractor’s experience.

3. Confusion over roles/duties of TWC and TWS.

4. Introduction of certified courses for TWC & TWS.

5. Awareness that organisations other than TW contractors don’t appreciate their involvement.

Frank

FOREWORDINTRODUCTION

and Principal Changes

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Foreword & Principal Changes• intended to be used by all organisations but lacked detail other than for PC

• updated in accordance with CDM Regulations 2015• As Bragg intended PC’s TWC retains overall control for all TW on site

• terms and definitions updated • description of temporary works added• includes recommendations on partial factors for TW designers

• safety issue in Section 3 has been advised

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Foreword & Principal Changes• Partial revision in 2011 and following items reviewed and confirmed– BS 12812 exists in parallel for limit state design of Falsework

– Design Classes A, B1 & B2 ‐ no advice on Class A so BS 5975 Section 3 applies

• Little construction work undertaken by PC ‐need to reflect this and

• CDM states ALL contractors should plan, manage and monitor their own works and liaise with others i.e. CO‐ORDINATE

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Introduction

Additional background •BS 5975 still based on Bragg (1974) but need to remember West Gate Bridge (Yarra Bridge)‐ see ICE Publication TEMPORARY WORKS Principles of Design and Construction Second Edition (December 2018)

– Causes of collapse included: client not selecting a suitably experienced contractor and; designer not responding to contractor queries on temporary conditions of the permanent works

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Written QUESTIONS• Q1 New BS5975 is 3 x size of previous version; Why?• A Revision to suit CDM, additional pages for Overview

(TWf requested a Lite version), needed Procedures forClients, Designers and Contractors other than PC as they were not implementing procedures.

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• Q1 SMEs struggle with current version and will find thistoo complex linked to

• Q4 Why organisation focussed approach?• A We tried both organisation and function but found

organisation worked best. Also it is back to back withCDM Regulations. SMEs can find the relevant pagesmore easily as they are together under contractors(other than PC ) and work for SMEs under contractto the client or the PC.

Peter

CLAUSE 5 OVERVIEW & TRAINING&

CLAUSE 6 PROCEDURAL CONTROL

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QUESTION TIME

A. BS 5975 Section 2 Procedural control

B. BS EN 12812 Performance Requirementand General Design of Falsework

C. The Work at Height Regulations 2007

D. CIRA C761 Tower Crane Foundation and Tie Design

E. Guidance L153 to CDM Regulations 2015

F. The Highway Code

Which of the following is mandatory?

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QUESTION TIME

A. Anything that is not “permanent”

B. What contractors use to build things

C. Work not paid for by the client

D. Part of the works that allow or enable construction of the permanent works

E. Includes the site compound, TV and film sets, advertising hoardings etc

F. Something else

What do you mean by “temporary works” ?

1 of 5

G. Hoarding?H. Mobile towers?I. Access scaffold?J. Crane outrigger foundations?K. Excavation to repair a 150 dia water main?L. Barge carrying crane, piling hammer,

generator & sheet piles etc.?

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What do you mean by “temporary works” ?

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BS 5975 “Temporary Works”“Temporary Works” is not defined.

Temporary works can be described as providing an “engineered solution” that is used to support or protect either an existing structure or the permanent works during construction, or to support an item of plant or equipment, or the vertical sides or side-slopes of an excavation during construction operations on site or to provide access. It is used to control stability, strength, deflection, fatigue, geotechnical effects and hydraulic effects within defined limits.

First clause in the overview is 5.1.1.1:-

3 of 5

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Clause 5.1.1.1 continuedTemporary works includes but is not limited to:-

a) Supporting or protecting either existing or new during construction, modification or demolition

b) Stability during construction, pre-weakening etc

c) Securing, providing access to site/workplace, including segregation of pedestrians / vehicles

d) Support or restrain plant (inc water-borne)

e) Provision of earthworks, slopes; divert water courses

f) Provide work platforms on land or water

g) Provide measures for noise, dust, fume, air quality etc

h) Protection to services

i) Facilitate testing (e.g. pipe tests, floor load capacity etc.

4 of 5

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Karnuk Temple, LuxorBuilt by Rameses III about 1170 BC

Temporary works of

earth ramps

Frank & Peter were not consultants on this contract!5 of 5

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The three fundamental principlesfor controlling temporary works have NOT changed

ONE: All organisations have a duty to manage and control their work.

TWO: The contractor is responsible forbuilding the permanent works, and thatincludes any associated temporary works necessary.

THREE: ONE person should take overallresponsibility for managing the TW.

( BS5975:2019 accepts that on very large sites duties can be allocated for defined areas ) ( 5.1.1.10 )

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5.1.1.7 One of the main aims ofthe procedure and the methodof work adopted should be to minimize the chance of errorsbeing made and to maximisethe chance of errors beingdiscovered if they are made.

REMEMBERSource: BS 5975:1982 to date !

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5.2 Training

• the procedures outlined in Section 2 of BS5975

• understand and be able to operate the companytemporary works procedure

• the risk management aspect associated with TW

• technical knowledge relevant to both the role andcomplexity of the work; and

• practical knowledge relevant to the complexity.

5.2.1 All those managing TW should have, as a minimum, an understanding of :-

5.2.3 Those procuring training should assess theactual trainer for competence, not the training provider:

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BS 5975:2019 The persons mainly involved.

Designated Individual (DI)

The PC’s Temporary Works Co-ordinator (PC’s TWC)

The Temporary Works Co-ordinator (TWC)

The Temporary Works Supervisor (TWS)

The senior person in the organisation responsible for establishing and maintaining the TW procedure, and appointing TWC’s and TWS’s if required.

The competent person appointed by the PC to manage and control all the TW on a site/project.

The competent person appointed by the organisation contracted to manage their own organisation’s TW. The person will be responsible to their DI & PC’s TWC

The competent person appointed by the organisation responsible to and assisting the TWC.

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BS 5975:2019 The committee’s problem

How do you rewrite the 2008 procedures written specifically for “main contractors” to suit the many types and levels of organisations?

From housebuilders, painters, highways workers, utility suppliers, railways, medium sized contractors,

specialist contractors, client contractors, large contractors on linear projects (roads and railways) to

nuclear power stations, HS2 and CrossrailANSWER - WITH GREAT DIFFICULTY

The DPC comments in September 2017 and the TWf in particular recently, highlighted the need for a simple explanation at start.

Solution adopted was to write an introductory “overview”and summary of likely control methods, building up the complexity with simple diagrams.

This is probably a first for a British Standard !

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Responsible for:Designers complyCo-operateCo-ordinatePass Information

ClientContractor

ManagingSubcontractor

Principal Designer

TWD SupplierTWD

TWD Other DesignersPWDTWD

In-houseTWD

Subcontractor

Principal Contractor

PWD

ClientBS 5975:2019 Clause 5 Overview - Organisations

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PrincipalContractor

CLIENT

CDM Coordination between Designers

PermanentWorks

Designer

PrincipalDesigner

TemporaryWorks

Designer

TWSupplierDesigner

Responsible for:Designers complyCo-operationCo-ordinationInformation

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Project or Site

Contractor

Temp Wks

CLIENTcontract

TemporaryWorks

Supervisor

Temp Wks

Temporary Works Co-ordinatorAppointed

Figure 2 a)

The single contractor on small project

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Main Project or Site

Principal Contractor (PC)

Temp Wks

Part of Site oranother

Site

Temp Wks

CLIENT

contract

TemporaryWorks

Supervisor

Principal Contractor’s Temporary Works Co-ordinator

appointed

Temp Wks

TemporaryWorks

Supervisor

Figure 2(b)

Several contractors

client appoints PC

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CLIENT

contract


appointed

Small Site

Temp Wks

TemporaryWorks

Supervisor

Small Site

Temp Wks

TemporaryWorks

Supervisor

Small Site

Temp Wks

TemporaryWorks

Supervisor

Figure 2 (c)

Contractorhas several small sites

(eg housebuilderor

utility company

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Projector Site


CLIENTcontract


appointed

cont

ract

Sub- Contractor

TemporaryWorks

Supervisor

Temp Wks

appointed

Temp Wks

Figure 2(d)

PC appoints subcontractor to implement own

temporary works

Sub contractor does NOT have ability to

manage the TW

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Well defined area X of Project or Site A


Temp Wks

contract

TemporaryWorks

Supervisor

appointed

Principal Contractor’sTemporary Works Co-ordinator

Temp WksTemp Wks

TemporaryWorks

Supervisor

appointed

Temp Wks

Well defined area Y of Project or Site A

Principal Contractor’s LeadTemporary Works Co-ordinator

(include co-ordinate interfaces)

Interface

CLIENT

Figure 2(e)


PC on a large and/or complex site

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BS 5975:2019 Managing Contractors

Another contractor, if deemed competent,can also manage Temporary Works.

The PC’s duties can be delegated, but responsibility always remains with the PC’s TWC.

As the PC has overall responsibility for all TW on the project and well defined area within it, the PC’s DI must ensure that the contractor has the skills and expertise - this includes the PC’s DI approving the contractor’s procedures.

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Project or Site



CLIENTcontract

appointed

Managing Sub- Contractor

Temporary Works Co-ordinator(manage and/or design)

Temporary WorksSupervisor

Temp Wks

cont

ract

appointed

Figure 3(a)

Temp WksTemp Wks

PC appointsa managing

sub contractor

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Projector Site



CLIENTcontract

appointed

Temp Wks

cont

ract

Client’s Contractor

Temporary WorksSupervisor

Temp Wks

appointed

Temporary Works Co-ordinator(manage and/or design)

Figure 3(b)

Client appointsa contractor

for work whichincludes TW

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QUESTION TIME

Who appoints the Temporary Works Co-ordinator ?

A. The Human Resources Department

B. The Client, on advise of the PWD

C. The Principal Contractor

D. The Designated Individual of the contractorapproved to manage their company’s

temporary works

E. A company director

F. The Project Manager

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Implementation Risk Classification of TW

Classifications often seen in company procedures are

Minor , Normal and Specialor Class A, Class B and Class Cor Type 3, Type 2 and Type 1

BS5975 Table 1 classes of Implementation Risk for temporary works with level of risk, permits required and gives suggested control measures:-

Note: BS EN 12812 (falsework) uses Class A, B1 & B2

Very low risk, low risk, medium risk or high risk

Identical temporary works may need same design but in a different location have different risk!

** DO NOT CONFUSE **

** DESIGN CHECK CATEGORY **

** WITH

**

** IMPLEMENTATION RISK **

** CLASSIFICATION

**

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Published by BSI with Temporary Works Forum

January 2017 £99 42 pages

PAS 8811 Temporary works – Major infrastructure client proceduresCode of practice

2 of 3

Introduces:

Type Classification N, S, P

Consequences of Failure RiskCFR0, CFR1, CFR2, CFR3

Design Complexity RiskDCR00, DCR0, DCR1, DCR2, DCR3

Categories of Design Check 0 1 2 3DCR00 includes SELF CHECKING !

Annex A - Standard Forms

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PAS 8811 Temporary works – Major infrastructure client procedures

3 of 3PAS 8811 Page 20

5.4 Execution Risk TEXT

5.5 Design Checking TEXT

5.6 Adoption of peer reviewTEXT

Majority of page in Blue text is for information ONLY!

Typical page

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BS 5975:2019 What procedure has changed?

BS 5975:2008 required “Every organisation involved in temporary works should have a procedure for control of temporary works for their organisation.”

The 2011 amendment added a note explaining that typical organisation can include:-

“clients, management contractors, sub-contractors, suppliers and consultants.”

BS5975: 2019 has NOT changed this requirement.

To promote each organisation knowing what to do, the 2019 version is structured by listing the roles and duties of the various organisations:-“clients, domestic clients, PW designers, TW designers, PDs,

PCs, contractors other than PC, third-party contractors,and suppliers/manufacturers.” FRANK WILL EXPAND

Audience QUESTIONS

Questions on

Clause 5 Overview & Training

&

Clause 6 Procedures

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BS 5975:2019 - Presentation Topics

Section One Clause 5 Overview and Training( Including contractual interfaces )

Section Two Clause 6 Procedural Control( Including new Implementation Risk table)

Frank Clause 7.0 Clients

Clause 8.0 Designers

Clause 9.0 Contractors

Clause 10.0 Suppliers

Specific explanatory text by organisation

Clause 6 re‐capDefinition of which organisations should have

a procedure has changed :‐•6.1.1.1 When a project has, or might be

anticipated to have, the requirement for any temporary works, the organizations listed in 6.1.1.2 should have and implement a procedurewhich outlines how that organization is to discharge its duties in relation to temporary works.

•This then identifies clients, designers, contractors (all including the PC) and manufacturers/suppliers

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Clients & Designers• 5.1.1.1 Temporary works can be described as providing an

"engineered solution" that is used to support or protect either an existing structure or the permanent works during construction, or to support an item of plant or equipment, or the vertical sides or side‐slopes of an excavation during construction operations on site or to provide access. It is used to control stability, strength, deflection, fatigue, geotechnical effects & hydraulic effects within defined limits.

• Discussion ‐ taking previous discussion on what temporary works are:

• Which projects would not have any temporary works?

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7.0 Clients• Check that any contractors and any designers they appoint have the necessary experience in relation to the temporary works which may be expected in their contract.

• Cl 7.1.3 client advises directly appointed contractors that PC to approve their procedure and has full responsibility for TW on project through the PC’s DI.

• This is repeated & cross referenced in both the PC’s and Contractor’s responsibilities.

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7.0 ClientsClient should :•ensure PC is co‐ordinating ALL TW on the projectand working in accordance with its procedure.

How this is done depends on the client and project.

•identify assets which may be affected by TW•identify schemes which require formal approval•identify hold points•provide information to allow the PD or PC to

design, construct and remove temporary works

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7.0 Clients

• Cl 7.1.4 & 5 if client is PD and / or PC then the client must have proceduresoutlined for PD and procedures outlinedfor the PC too.

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8.0 Designers

• References to TWC mean both PC’s TWC and managing contractor’s TWC

• Although new procedure it is based on CDM Regulations except the Designers (including PD) are required to liaise with TWC. Could be direct with TWD and TWC copied in if agreed.

• Should respond promptly to queries from TWC ‐ again a problem with no response as experienced at Yarra Bridge collapse!

441 of 2

8.0 Designers

• Lead Designer (TW) ‐ solution to problem on NR Bridge GE 19– Various parts of bridge launch designed by different organisations

• Signs off the TWD when various parties design different parts of a TW Scheme– Reviews all designs and signs off an overall design certificate.

– May have a Lead Design Checker who signsoff an overall design check certificate.

452 of 2

9.0 Contractors

• As for all DI’s, the contractor’s DI should be a member, or directly responsible to a member of, the main or supervisory board. See clause 6.1.2.1

• The duties on the PC (was Main Contractor) have remained the same in relation to its own works BUT additional dutieshave been added in relation to the work of other contractors

• The duties on other contractors are as the basic duties on the PC in relation to managing their temporary works. i.e. write a procedure, appoint a competent TWC and

co‐ordinate their temporary works (including with other contractors)

461 of 11

• This is where we had difficulties with some not understanding that subcontractors could manage their own TW. It has been an option since 2008. It is NOT done through the subcontractor’s TWS !

• 9.1.8 Where contractors are appointed by the client and/or PC, the PC's DI should ensure that contractors’ temporary works procedures are satisfactory. The contractor should supply evidence of how the procedure has been implemented on previous contracts and which type of temporary works the contractor has been responsible for.

• NOTE Attention is drawn to the CDM Regulations 2015and the HSE Guidance Notes L153 on the Regulations].

• (ALL Contractors to plan, manage & monitor their own works.)

472 of 11

9.0 Contractors

9.0 Contractors

Discussion ‐Which Contractors does this mean?

• ALL ?• Client appointed ?• Specialists ‐ RC Frame, Marine, Demolition ?• Not general sub‐contractors ?• Cannot generalise ‐ PC’s DI must assess

483 of 11

9.0 Contractors

• 9.2.2 includes a requirement that the PC’s DI should check that contractors appointed by the PC, the client or a third party have a satisfactory procedure.

• This clause builds on the clause under clients which requires them to inform the contractors that the PC’s DI will check their temporary works procedures.

494 of 11

• PC’s DI in relation to other contractors– When contractor’s procedure should be provided– How the procedures should be checked– What if procedure is inadequate?– How PC’s TWC should interact with the

contractor’s TWC– How & when PC’s TWC should verify the design

briefs from the contractor– How & when PC’s TWC should check the

design certification

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9.0 Contractors

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• Confirm that the contractor’s procedure is satisfactory ( or otherwise !)

i.e. The contractor is deemed to have the knowledge, skills, experience andorganizational capability to manage itsown temporary works.

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9.0 Contractors

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• Contractors duty after appointment • The PC’s DI should be provided with a copy of the assessment of the competence of the contractor’s PROPOSED TWC and confirm acceptance (or otherwise) through the PC’s TWC.

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9.0 Contractors

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PC’s responsibility for Temporary Works –(clause introduced following comment from Hinckley Point)

9.3.2.5. Where a particularly technically or logistically complexproject can be split into more than one well‐defined area,then a PC’s TWC may be appointed for each area. Each individual PC’s TWC should be responsible for all the temporary works in the area allocated, irrespective of which organization carries out the temporary works in the area. Only one PC’sTWC should be responsible for a specific area. One of these individuals should be appointed as lead PC's TWC to manage the interfaces between the areas.

NOTE: On a contract such as a motorway or railway the project could be split into sections, having a PC’s TWC for each section, provided that the interface is clearly established. It is extremely rare that a building project would justify more than one PC’s TWC.

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9.0 Contractors

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9.3.3 covers appointment of TWCs NOTappointed by the PC

•Role has the same responsibilities as basic PC’s TWC but note that the PC’s TWC has additional duties to ensure the contractor’s TWC is working in a well‐defined area and doing as the contractor’s procedure requires.

More on this from Peter later

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9.0 Contractors

9 of 11

Appointment of TWS•This applies to both PC & other contractors •The TWS is NOT a sub‐contractor’s TWC

by another name.•The TWS role NEVER included a requirement

to co‐ordinate temporary works.•The TWS role is to inspect temporary worksduring their (stages of) construction / erectionand only sign a permit to load/unload IFthey are deemed competent to do so.

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9.0 Contractors

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• 9.5.2.1 The client contractor’s roles and responsibilities are the same as those for the contractor appointed by the PC and should be in accordance with 9.5.1.1 to 9.5.1.7.

• 9.5.2.3 The PC’s DI has a responsibility to ensure the client contractor’s procedures are satisfactory

(see 9.2.4)

• These two clauses indicate that the PC has responsibility for ALL temporary works on the project and that the client contractor SHOULD submit their TW procedure for approval.

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9.0 Contractors

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10.0 Suppliers/Manufacturers

Written by Chief Engineer of a major supplier10.3 The supplier's procedure should cover:

– a) equipment conforms to the published technical data;

– b) original design of components, verification and production of technical information forindividual and assemblies of proprietary items;

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continues

1 of 3

– c) ensuring manufactured and repaired itemsconform to original design requirements forinitial and all subsequent production throughapplication of robust quality control;

• I have experience of a supplier changing fabrication details but NOT checking how the design was affected!

– d) material handling and transportation;– e) maintenance and repair of items that are hired

or offered for second‐hand sale; and– f) equipment substitutions when the original

component is not available.

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10.0 Suppliers/Manufacturers

continues2 of 3

Suppliers / Manufactures should provide :• Technical information (data sheets)• Design data• Information for safe use of the equipment• Standard solutions (as appropriate.)

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10.0 Suppliers/Manufacturers–If they carry out design or erection (construction) of works then they should have procedures as outlined in clause 8 and

clause 9 respectively.

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Audience QUESTIONS

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Questions on

Clause 7.0 Clients

Clause 8.0 Designers

Clause 9.0 Contractors

Clause 10.0 Suppliers/Manufacturers

Peter

• Clause 11 TWC• Clause 12 TWS• Clause 13 Design of Temporary Works

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Duties of theTemporary Works

Co-ordinator (TWC)

Duties of theTemporary Works

Co-ordinator (TWC)1975 First recommendation for constructor to

appoint a properly qualified TWC.

1982 BS5975 recommends the constructionorganisation involved appoints a

“Falsework Coordinator “

2008 BS5975 renames to TWC and liststhe principle activities of the TWC

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BS 5975: 2019 Clause 11 Duties of the Temporary Works Co-ordinator

1 of 7continues

BS 5975:2011 gave 19 activities/duties

BS 5975:2019 has 23 duties for PC’s TWC,plus further 6 duties when other

contractors on site.

and has 26 duties for a TWC. HEALTH WARNING

The following “death by PowerPoint”

highlights what has ACTUALLY changed

642 of 7

a) co-ordinate all temporary works;

b) ensure a temporary works registeris established and maintained;

ExistingTWC activity

ManagingTWC

PC’sTWC

and ensure liaised with PC’s registerc) ensure responsibilities allocated accepted

This is the role of the DI, not the TWC

d) ensure a design brief is prepared, isadequate, and accords with site;

e) ensure that residual risks identified bythe PWD are included;

f) ensure a TW design is carried out;Stated in role of PC’s TWC

653 of 7

continues


ManagingTWC

PC’sTWC

g) ensure design check carried out by someone not involved in original design

Where required confirm to PC’s TWC

k) ensure that appropriate checks are made;l) ensure proposed changes are checked

against design and action taken;

h) where appropriate, ensure design madeavailable to interested parties,

i) register or record relevant documents;

j) ensure on-site receive relevant details, any limitations, notes, method statements;

In hindsight should be in TWC !?

664 of 7 continues


ManagingTWC

PC’sTWC

m) ensure agreed changes, corrections arecorrectly carried out; andadvise designer of changes/ modifications

n) ensure appropriate maintenance ;

o) ensure permit to load issued after check;

p) when confirmed structure has strengthand/or stability, ensure permit to unload( take out of use ) is issued;

q) ensure safe system of work in placefor the dismantling of temporary works;

and for erection of TW.

675 of 7 continues


ManagingTWC

PC’sTWC

r) ensure relevant information for health &safety file transmitted to PD

or PC’s TWCs) Ensure TWS operate approved procedure


ManagingTWC

PC’sTWC

NEWTWC duties

NOW the new duties1) ensure relevant TW information received

from client, PD, and/or PWD

4) ensure design brief issued to TWD

2) ensure other TW in vicinity referenced in design brief

3) pos’ copy brief to PC’s TWC and confirm no adverse effects on any vicinity TW

686 of 7

NEWTWC duties

ManagingTWC

PC’sTWC

5) ensure client / 3rd party approvals received6) if discrepancies found in check prevent

load/unload until rectifiedNew duties for a Managing TWC

7) Ensure PC’s DI approves the management

8) Ensure which procedure the PC’s DI has agreed (PC or contractor procedure)

9) Awareness of any limitations in use

10) Liaise PC’s TWC on understanding of types & limits on use permits/hold points

continues

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NEWTWC duties

ManagingTWC

PC’sTWC

PC’s duties to Other Contractors

11) ensure TWDs and checkers competentand verified by organisation’s DI

12) ensure PC TWC rectification instructionscarried out and to PC TWC satisfaction

13) receive contractor’s DI’s assessment ofcapability of TWC & TWS(s)

14) provide relevant TW information15) define interfaces between PC & others

16) receive briefs; confirm no adverse effect17) receive relevant TW info, designs, certs..18) inspect contractor’s TW as necessary

WE SURVIVED !

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QUESTION TIME

A. Can a TWC carry out designand/or design checking?

Although not in role, BS5975 does NOT preclude any TWC from carrying out design and/or

checking (NOT BOTH) if they are competent and it is within their experience based on the

complexity of project.(Clauses 11.2.2.12 & 11.3.2.4)

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QUESTION TIME


B. Should the TWC be an employee of the organisation managing the works?

Yes

The PC’s TWC or TWC should be either an employeeOR an employee of an organisation contracted to

provide the services of a TWC on behalf of the contractor for all the organisation’s temporary works on the site/project area.

(Cls 9.3.2.5 & 9.3.3.1)

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QUESTION TIME



C. Is a proprietary supplier of temporary works equipment always a TWD ?

Yes

Yes

Not necessarilye.g. Could provide “Standard Solution”

or data sheet for in house design.

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QUESTION TIME



C. Is a proprietary supplier of temporary works equipment always a TWD ?

D. Should a PWD approve the TW ?

Yes

Yes

Notalways

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January 2016

£ 123

64 pagesSource: BSI publications

PAS 8812

Temporary works –Application of

European Standards in design - Guide

75

Clause 13.3.9 Partial Safety Factor

For the design of steel or aluminium elements of temporary works, the partial factor for material at ultimate limit state should be a minimum of 1.1

Where temporary works are designed, manufactured and assembled for a SINGLE use using similar details and execution standards as adopted for permanent works then the designer may justify the use of a lower partial material factor.

76

QUESTION TIME

A. Should you design stable structures ?

and

1 of 4

B. Should you consider all likely loads ?

This is NOT the Law

BS5975 says “designer should take into account”

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19 (2) Any buttress, temporary support or temporary structure must-

(a) be of such design and installed and maintained soas to withstand any foreseeable loads which maybe imposed on it.

19 (1) All practicable steps must be taken, where necessaryto prevent danger to any person, to ensure that any new or existing structure does not collapse if, due to carrying out construction work, it-

(a) may become unstable; or(b) is in a temporary state of weakness or instability.

2 of 4

Construction (Design and Management) Regs 2015 Reg. 19 - Stability of Structures

The LAW says you MUST not “should” :-

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Foreseeable Loading !!

3 of 4

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( c) the resistance to overturning or rotational failure;

(d) positional stability; and

(e) the effects on the permanent works and itssurroundings.

13.3.10 For each temporary works design, the designer should take into account:-

(a) the structural strength and stiffness of theindividual members and their connections totransmit the applied forces safely including anyp-delta or feedback effects;

(b) the lateral stability of both individual membersand the structure as a whole;

4 of 4

BS 5975:2019 Design Guidance

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BS 5975:2019 Design Check Categories - Table 2

Category Scope Independence

2More complex design. by individual not excavations, structural involved in design steelwork, foundations, and not consulted bytop restraint assumed. the TW designer

3 Complex or by another innovative design organisation

1 Simple design by another member of design team

Restricted to standard solutionsO

Site issue - by another member of site teamor design team

Categories unchanged

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BS 5975 The Future ?

BS 5975:2019

PartOne

BS 5975 – 1 : 20xx

Code of practice -Procedural control ofTemporary Works

BS 5975 – 2 : 20xx

PartTwo

Code of practice - Falsework2 - 1 General2 - 2 Loadings / Actions2 - 3 Analysis2 - 4 Limit state design2 - 5 Permissible stress design

Business case for this work already submitted to BSI

82

Temporary WorksPrinciples of Design

and Construction

34 Chapters

Second EditionPublished December 2018

528 PagesSource - ICE Publishing

£145Chapter 1 Safety & Chapter 2 Management

should be compulsory reading for graduates

and anyone new to temporary works!

83

The End Final Questions ?

bs5975:2019 overview of procedures - scafftag...1 bs5975:2019 overview of procedures 25 july 2019...

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