5.5 Structures certification and inspection
Detailed design should not normally be undertaken until we have given our Approval in Principle. The design must comply with the Approval in Principle and, should any variations prove necessary, we must agree to them before they are implemented. Such variations must be recorded on an addendum to the Approval in Principle, signed by both the Designer and the TAA.
Any modifications or additions to the Approval in Principle during the design stage will be subject to the same procedures as the original submission.
The Designer shall be responsible for the applicability and accuracy of all computer programs used and shall also ensure the validity of the programs for each application.
Designs and Contract Drawings (including bar bending schedules) shall be checked under the parameters given in CG 300.
The Checker shall carry out a comprehensive examination of all aspects of the design and any proposed departures, and shall ensure that it complies with our requirements. The Checker shall ensure that the calculations are translated accurately into design details, drawings and specification clauses.
The Checker shall be responsible for checking, with due professional skill and care, in accordance with the Approval in Principle, and shall draw the attention of the Designer and TAA to any aspect of the agreed Approval in Principle where changes are considered necessary.
The Checker’s analytical work shall be independent of that of the Designer and carried out without reference to, or exchange of, calculation sheets or similar information between the Designer and Checker.
The Checker shall be responsible for the application and accuracy of all computer programs used and shall ensure the validity of the program for each application. Provided that the Checker agrees with the input, the Checker may use computer output generated by the Designer for the design.
It is not intended that the start of the check should await the completion of the design. Both may proceed together as far as possible to ensure that agreement or resolution of differences is obtained progressively through the design period. Although independence between the Designer and the Checker must be maintained, and the methods they employ need not be the same, consultation can take place between the teams to ensure that the results they are obtaining are directly comparable.
The TAA may call a pre-certification meeting, for selected structures with the Designer and Checker, to discuss their findings prior to accepting Certificates.
When the design and check of each structure has been completed, the appropriate certificates should be sent to the TAA with original signatures, for, if appropriate, endorsement. All departures from, and aspects not covered by, standards agreed at the Approval in Principal stage, must be recorded on the certificates for our endorsement.
A copy of the General Arrangement drawing of the structure must accompany the Certificate for a Category 0 structure.
The two signatories submitting the Certificate must clearly indicate their name and office. One, a chartered Engineer, must be the team leader responsible for the design or independent check and the other Partner, (Consulting Engineer) who may delegate this authority for Category 0 and 1 structures.
Any proposed substitute or additional bridge works specification clauses required, and Bar Bending Schedules, should be identified and are to be included on the certificates together with a list of drawings, with appropriate revision markings.
5.5.4 Subsequent procedure
Tenders for a scheme must not be invited until Technical Approval procedures have been completed for all structures in it except where temporary and/or proprietary structures are specified in the contract and the choice is to be made after return of tenders.
Temporary and/or proprietary structures proposed by a contractor for public use on or over a Public Road will be subject to the normal Technical Approval procedures and subsequent certification by a chartered civil or structural engineer.
A set of drawings for each certified structure shall be submitted to us at the time of tender for reference during the period of contract.
An alternative design by a contractor, which appears to be viable to the Engineer for the Works, will be subject to Approval in Principle by the TAA. An Approval in Principle document must be submitted with the alternative tender and final approval will not be given until Certificates for the design and independent check have been accepted. The Engineer for the Works will be the Independent Checker unless we agree otherwise.
It is the responsibility of the Designer to inform us of any amendments to the design, during construction, which have structural implications and such amendments should be included in an addendum to the Approval in Principle. Certificates revised to take account of such amendments shall be submitted to us for acceptance. Only where the value of the associated Variation Order is within that for which the Engineer for the Works has delegated powers and the structural input is negligible may the amendment be implemented before we have accepted the Certificates. Additionally, where the proposed erection procedure induces different stresses in the completed structure from those anticipated in the design, the changes will need to be covered by additional certificates from the Designer and Checker, and we must issue our acceptance before erection commences.
The Designer will assume the responsibility for the design of the permanent works.
Works should not commence on site until we have endorsed all relevant Certificates.
The Designer must complete a testing schedule in the format outlined in Series 100 of the “Manual of Contract Documents for Highway Works”, for approval. This testing schedule must describe the absolute minimum testing to be undertaken by the Contractor.
5.5.6 Loading and headroom
All road structures (structures supporting the road or for construction above an existing adopted or proposed adopted road) must be designed using DMRB standard CD 350 The Design of Highway Structures.
Traffic Loading is in accordance with BS EN 1991-2, Eurocode 1: Actions on structures – Part 2: Traffic loads on bridges, as implemented by the UK National Annex (NA) to BS EN 1991-2.
Combinations of actions shall be in accordance with CD 350 and NA BS EN 1990 and as outlined in PD 6694-1:2011.
Selection of Special Vehicles (SV), Load Model 3 (LM3) shall be determined through consultation with the TAA.
Road geometry and cross sections for all road structures and minimum headroom for structures over roads shall be in accordance with DMRB standard CD 127 Cross-sections and Headrooms.
5.5.7 Notice of Operations
When a new or modified structure is to be adopted, two weeks’ notice must be given of works commencing on site.
The developer or their contractor must give us a minimum of 2 working days’ notice of the following operations: -
- Commencement of each pavement layer to the carriageways, footways, footpaths and verges.
- Each concrete pour (including blinding) and commencement of steel fixing where reinforced concrete is used.
- Backfilling to abutments and retaining walls.
- Application of waterproof membrane.
- Prior to application of primer to steelwork and each following coating.
- Prior to erection of structural steelwork.
- Prior to pouring sealant/placing expansion joints.
- Prior to taking down any scaffold, after completion of that part of the works.
5.5.8 Construction Compliance Certificate
The Construction Compliance Certificate shall be submitted to us for acceptance and should refer to, if available, the relevant Approval in Principle, Design and Check Certificates, Specification and As-Constructed drawings.
5.5.9 Health and safety file for adopted structures
On completion of the works a separate Health and Safety File for each structure is to be prepared and submitted prior to adoption.
The Health and Safety File is to be completed in accordance with Construction (Design and Management) Regulations 1994. Details of all testing undertaken, (including manufacturer’s literature) must be included in the Health and Safety File. A statement setting out problems encountered during construction of the works and what corrective action undertaken must also be included in the Health and Safety File.
With respect to structures not proposed for adoption, including basement walls and cellar roofs, reference must be made in the Health and Safety File for the structure/building that approval must be sought from the Council prior to any alterations being undertaken.
Note: These webpages are for reference by developers of housing and employment sites in East Lothian. They provide guidance on transport infrastructure against which Planning Applications will be assessed and evaluated, and set out East Lothian Council's procedures regarding the construction and adoption of new roads in accordance with current legislation. These pages supersede all previous versions of our Standards for Development Roads document. Revisions 01/07/2023 Document release