INTERIM ADVICE NOTE /11
Interim Requirements for
Highway Structures
Technical Compliance Procedures
INTERIM ADVICE NOTE /11
INTERIM REQUIREMENTS FOR
HIGHWAY STRUCTURES
TECHNICAL COMPLIANCE PROCEDURES
Summary
Requirements for Technical Compliance of highway structure proposals. The procedures in this IAN replace the BD2 structures Approval in Principle procedures.
Instructions for Use
For projects or programmes of work where no structural proposals have yet been submitted to the relevant HA structures team at the date of this IAN, the new Technical Compliance procedures as given in this IAN are to be adopted, subject to any contractual limitations.
For all other projects the BD2 Technical Approval procedures will continue to apply and the aim is for the Technical Compliance procedures to replace them as soon as practical, but no later than end March 2012. For structural proposals initiated from April 2012 onwards the Technical Compliance procedures will be followed. The only exception will be structural proposals where there are ongoing contractual requirements to apply the BD2 Technical Approval procedures beyond March 2012.
For existing structure works programmes such as those prepared by Maintaining Agents and other organisations where there is a long term arrangement to deal with a programme of structural issues, there is to be a transition from the BD2 Technical Approval procedures to the new Technical Compliance procedures as soon as practical. This transition is not to extend beyond March 2012 unless there are contractual commitments beyond this date to apply the BD2 Technical Approval Procedures.
Table of Contents
Chapter
1. Introduction 3
2. General Requirements and Principles 11
3. Bridges and Other Highway Structures 18
4. Temporary Works 21
5. References 24
6. Enquiries 25
7. Notification 25
Annex A: Model Records of Design Principles and Records of Assessment Principles
Annex B: Notes for compiling Technical Standards and GuidanceSchedule
Annex C: Model Certificates
Annex D: Proprietary Manufactured Structures
Annex E: Special Requirements for Third Party Proposals of Temporary Works or Temporary Structures
Annex F Overview of Technical Compliance Procedures
Annex G Technical Compliance Review Procedures
1. introduction
General
1.1 This IAN specifies the Technical Compliance (TC) procedures for highway structures managed by the Highways Agency on motorways and other trunk roads or designated roads in England.
1.2 The requirements in this IAN replace the requirements in HA Standard BD 2. The new TC procedures must be followed in accordance with the implementation instructions given in Clauses 1.19 and 1.20,, although some structural proposals will continue to be subject to the Technical Approval (TA) procedures in BD 2, as detailed in the transition arrangements given in Appendix F of this IAN.
1.3 Procedures for the TA of highway structures have been in place for almost 40 years and during this period working practices and methods of procurement have changed. Also methods of structural design, assessment and maintenance have evolved, alongside quality assurance procedures.
A review of the alignment of the TA procedures with contractual roles and responsibilities, business needs and risks associated with whole structure life, from development of possible alternative solutions through to construction, maintenance, assessment, refurbishment, strengthening and demolition, has been completed. The conclusions from this review have led to the development of the Structures TC procedures for trunk road and motorway structures in England, as set out in this IAN. The key features include:
(i) The Checker will examine and agree design or assessment criteria and methods
(ii) A selective review of proposals will be carried out by the HA’s Technical Compliance Team (TCT)
(iii) Tunnels as well as associated Mechanical and Electrical Installation proposals are excluded from these TC procedures.
(iv) TC procedures do not apply to works to be executed under the terms of existing HA DBFO contracts.
(v) Requirements with respect to proprietary structures supplied in accordance with EU directive 89/106/EEC – the Construction Products Directive (CPD)
1.4 The TC procedures as described in this IAN generally require the proposer to submit a Record of Design Proposals (RDP) or a Record of Assessment Proposals (RAP) to the Checker and receive agreement of the RDP or RAP by the Checker before proceeding with any design or assessment. The Checker is required to submit each of the agreed proposals to the TCT for selective compliance review. The TCT review comments are summarised in a Design/ Assessment Compliance Report that is sent to the Checker for appropriate action. The completed design or assessment cannot be implemented until the Checker has endorsed the required certification. TC applies to proprietary products unless the performance of the structure has been declared in accordance with the requirements of the CPD and the structure will be used for its intended purpose.. This is subject to the conditions given in section 2.5 and Annex D. TC may apply to the installation of proprietary structures, as detailed in section 2.6.
1.5 The TC procedural requirements impose a discipline on the process that encourages good practice and should reduce the possibility of errors affecting structural fitness for purpose. Most importantly however, the procedures minimise the possible risks to highway users and others who may be affected. The procedures may be applied to any other circumstances where the HA considers the requirements to be appropriate.
Objectives
1.6 The fundamental objective of the TC procedures is to give increased assurance for the required construction, refurbishment or demolition of highway structures. This will help to ensure that the proposals are safe to implement, that any new structures procured are serviceable in use, economic to build and maintain, comply with the objectives of sustainability, have due regard for the environment and that they satisfactorily perform their intended functions. The TC procedures also ensure, as far as reasonably practicable, that highway users, the public and any others who may be affected are protected from adverse effects resulting from any work carried out to any highway structure.
1.7 TC provides procedures to demonstrate that the HA, in its capacity of highway authority, has carried out its duty to safeguard the highway users and others who may be affected.
Scope
1.8 Subject to any exclusions expressly stated in this document TC procedures must be applied for each scheme or programme of works to all Proposals (including private development) to construct, widen, assess, improve, repair (where structural integrity may be implicated) or demolish a structure within the highway boundary. It must also be applied to Proposals for highway structures that are outside the highway boundary, where the structures are to be adopted by the HA.
1.9 The scope of TC must be as specified in Chapters 3 and 4.
1.10 It is recommended TC procedures also be applied to Proposals for structures that are outside the highway boundary where the design, construction, maintenance or demolition of the structure may affect the highway, highway structure or the safety of the highway user.
1.11 In cases where the design and construction of a Third Party proposal are outside the expertise of the HA, the TCT are to consider implementing the special requirements given in Annex E.
1.12 TC procedures are not necessary where there are no public safety issues e.g. temporary works in green field sites or temporary works within the highway boundary during full road closures where there will be no interface with the public. However, TC procedures apply to temporary works where the permanent works Proposal has identified the need for an independent check.
Contractual Responsibilities and Procedures
1.13 TC does not in any way modify or reduce the contractual and statutory responsibilities of any party for the work carried out or the legal responsibilities of professional engineers.
1.14 This IAN has been written such that it is applicable in principle to all current forms of contract (with the exception of existing DBFO contracts, which are not covered by this IAN) The procedures, format and terms used in this IAN, including the model RDP and RAP forms and certificates provided in Annexes A and C, are intended to be contract-neutral and are to be taken as models. Different procedures, format or terms may be used subject to the agreement of the TCT.
1.15 In departing from the procedures, format or terms used in this IAN, users must ensure that the following objectives are achieved:
(i) That the required design or assessment principles are formally agreed prior to award of any contract, to a sufficient extent to ensure contractual compliance.
(ii) That construction is not allowed to proceed until there is formal completion of Certification in accordance with the requirements in this IAN.
1.16 The model RDP & RAP forms and certificates provided in Annexes A and C must be amended and agreed with the TCT to suit specific contract requirements. Timings and procedures must be identified in the scheme specific contract requirements.
1.17 The contract requirements may clarify whether the Proposals and the RDP or RAP are of an outline nature sufficient for the invitation or acceptance of tenders or whether they are comprehensive and sufficient for detailed design or assessment. The principles, detailed requirements and recommendations contained in this IAN should apply accordingly. The Outline RDP or RAP may be based on the relevant sections of the model RPD or RAP Annex A and is to be submitted to the TCT for compliance review.
1.18 For some forms of procurement, TC for the design would typically be completed in detail before tenders for carrying out the construction work required by the design are invited. For other forms of procurement, where the design has not yet been completed prior to inviting tenders, the TC process would typically only be partially completed during the tender period. Submission of a final detailed RDP or RAP would usually take place following award of contract. The TCT are to be consulted to agree the TC procedures where there are any uncertainties.
Implementation
1.19 This IAN must be used forthwith on all projects for the assessment, design, construction, operation and maintenance of motorway and all-purpose trunk roads except where procurement of works has reached a stage at which, in the opinion of the HA, its use would result in significant additional expense or delay progress (in which case the decision must be recorded in accordance with the procedure required by the HA). Exclusions from this requirement are given in the Transition arrangements set out in Appendix F of this IAN. All excluded structure proposals will be subject to the TA procedures in BD 2.
1.20 This IAN must also be used to implement the procedures for private development within the highway boundary. (See 1.8)
Mandatory Sections
1.21 Sections of this IAN containing mandatory requirements are identified by being contained in boxes. These requirements must be complied with or a prior agreement to a Departure from Standard must be obtained from the HA. The text outside boxes contains advice and explanation, which is commended to users for consideration.
Definitions
1.22 For the purpose of this IAN, the following definitions apply (see also 1.14):
Assessment Team / The group of engineers responsible for the assessment. It may comprise an appropriate mix of specialists under the direction of a Team Leader.Assessor / The organisation responsible for the overall assessment.
Category / The classification of the Proposals, which determines the need for TC, the form of check to be applied and the certificates to be prepared.
CDM co-ordinator / The person appointed by the client on a notifiable project to perform the duties specified in the Construction (Design and Management) Regulations 2007.
CE marking / The marking that the manufacturer applies to declare compliance of a product with relevant EU product directives including the directive 89/106/EEC the Construction Products Directive.
Checker / The organisation responsible for agreeing proposals in RDPs and RAPs, as well as carrying out the independent check of the design or assessment and endorsing certificates. The appointment of a Category 3 Checker is subject to agreement with the Technical Compliance Team.
Check Team / The group of engineers responsible for the independent check of the design or assessment. It may comprise an appropriate mix of specialists under the direction of a Check Team Leader. The Check Team Leader is also responsible for the review of the content of the design RDP or assessment RAP and formally agreeing it. Checking Team Leader will formally endorse Design/ Assessment Certification in the capacity of the Checker.
Compliance Review / Review of RDP and RAP proposals carried out by the HA Technical Compliance Team
Contractor / The organisation contracted by the HA to undertake the construction works on its behalf.
Contractor’s Representative / A representative of the Contractor, with responsibility for overseeing the construction works.
Departure / Criterion which departs from, or is an aspect not covered by, the standards contained in the Technical Standards and Guidance Schedule.
Designer / The organisation responsible for the overall design
Design Team / The group of engineers responsible for the design. It may comprise an appropriate mix of specialists under the direction of a Design Team Leader.
Eurocodes / As defined in BS EN 1990
Execution / As defined in BS EN 1990
Foundation / Generally in a highway structure that part of the substructure in direct contact with and transmitting load to the ground. Note: Specific elements forming the foundation are to be given in the RDP or RAP.
Geotechnical Design Report / A report that contains geotechnical information relevant to the design or assessment in accordance with current HA requirements.
Highways Agency / HA / The Highways Agency
Highway Structure / Structure or installation coming within the scope of this IAN and situated under, over or adjacent to a motorway or other trunk road or road designated by the HA.
Lighting Column System / Range of combinations of column heights and lengths of brackets together with the weights and windage areas of lanterns and attachments for which the column has been designed.
Maintaining Agent / MA / The organisation with delegated responsibility for the maintenance of a Highway Structure.
Minor Structures / For the purposes of this IAN:
(a) Lighting columns and wall mounted brackets