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BS5975:2019Overview of Procedures
25 July 2019
Peter F. PallettFrank MarplesMember BSI committee
since 1977Chairman BSI committee
Member since 1998
2
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 }
3
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
4
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
5
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
6
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
7
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
8
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.
9
• 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
10
11
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?
12
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.?
13
What do you mean by “temporary works” ?
2 of 5
14
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
15
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
16
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
17
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 )
18
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 !
19
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:
20
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.
21
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 !
22
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
23
PrincipalContractor
CLIENT
CDM Coordination between Designers
PermanentWorks
Designer
PrincipalDesigner
TemporaryWorks
Designer
TWSupplierDesigner
Responsible for:Designers complyCo-operationCo-ordinationInformation
24
Project or Site
Contractor
Temp Wks
CLIENTcontract
TemporaryWorks
Supervisor
Temp Wks
Temporary Works Co-ordinatorAppointed
Figure 2 a)
The single contractor on small project
25
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
26
Principal Contractor (PC)
CLIENT
contract
Principal Contractor’s Temporary Works Co-ordinator
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
27
Projector Site
Principal Contractor (PC)
CLIENTcontract
Principal Contractor’s Temporary Works Co-ordinator
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
28
Well defined area X of Project or Site A
Principal Contractor (PC)
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)
Principal Contractor’sTemporary Works Co-ordinator
PC on a large and/or complex site
29
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.
30
Project or Site
Principal Contractor (PC)
Principal Contractor’s Temporary Works Co-ordinator
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
31
Projector Site
Principal Contractor (PC)
Principal Contractor’sTemporary Works Co-ordinator
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
32
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
33
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
**
1 of 3
34
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
35
Published by BSI with Temporary Works Forum
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
36
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
37
38
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
39
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?
40
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.
411 of 3
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
422 of 3
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.
433 of 3
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
50
9.0 Contractors
5 of 11
• 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.
51
9.0 Contractors
6 of 11
• 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.
52
9.0 Contractors
7 of 11
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.
53
9.0 Contractors
8 of 11
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
54
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.
55
9.0 Contractors
10 of 11
• 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.
56
9.0 Contractors
11 of 11
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;
57
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.
58
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.)
59
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.
3 of 3
Audience QUESTIONS
60
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
61
62
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
63
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
ExistingTWC activity
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
ExistingTWC activity
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
ExistingTWC activity
ManagingTWC
PC’sTWC
r) ensure relevant information for health &safety file transmitted to PD
or PC’s TWCs) Ensure TWS operate approved procedure
ExistingTWC activity
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
697 of 7
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 !
70
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)
71
QUESTION TIME
A. Can a TWC carry out designand/or design checking?
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)
72
QUESTION TIME
A. Can a TWC carry out designand/or design checking?
B. Should the TWC be an employee of the organisation managing the works?
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.
73
QUESTION TIME
A. Can a TWC carry out designand/or design checking?
B. Should the TWC be an employee of the organisation managing the works?
C. Is a proprietary supplier of temporary works equipment always a TWD ?
D. Should a PWD approve the TW ?
Yes
Yes
Notalways
74
Published by BSI with Temporary Works Forum
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”
77
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” :-
78
Foreseeable Loading !!
3 of 4
79
( 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 ?