Design Pipe Size and Fit Materials
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TECHNICAL SPECIFICATIONS All work shall be carried out, and the Works shall be constructed, in accordance with the Tender Documents or otherwise referred to herein or elsewhere in the Contract as describing the Works or the work. For purposes of this clause, the "Technical Specifications" shall include, but is not limited to the supply and delivery of all necessary materials, plant, equipment and labour required for stormwater pipe rehabilitation, including traffic control. It is also to include obtaining required permits and preparation of all the necessary documentation for the works to take place. The technologies and products recommended by the Contractor are to comply with AS2566.1, AS3500 and other relevant standards. Design The minimum required service life of the installed lining material is fifty (50) years. Loading should be assumed for a highly trafficable road unless specified otherwise. External loads (eg. earth loads, live loads, hydrostatic pressure), construction loads (eg. external grout pressure, plant movement), together with appropriate safety factors are to be considered in the design and selection of the pipeline rehabilitation treatment. The Contractor shall adequately select a product that suits the conditions. It is expected that the Contractor has extensive knowledge of trenchless pipeline rehabilitation products and construction techniques. The Contractor shall supply full details of design calculations and verification test data when requested by the Superintendent. Review of the Contractor’s design calculations and test data shall not be construed as acceptance of the calculations. Responsibility of the design and material quality shall remain with the Contractor. Pipe Size and Fit The contractor shall measure all pipes on site prior to ordering any materials to confirm the pipe diameters, any discrepancies are to be reported to the superintendent. If the contractor fails to measure the pipes accurately on site prior to installation they are then responsible for the replacement of the liner at their own cost. Lining systems shall not reduce the internal diameter of the existing pipeline by more than 10 per cent in pipelines with internal diameter DN of 525mm and smaller, nor more than 5 per cent in with DN greater than 525mm. The lining or replacement pipe material shall be such that any reduction in the pipeline's cross sectional area is compensated by the increased flow capacity through the reduced roughness of the rehabilitated pipe. All lining systems are to have a fit, or fixing system, that sufficiently holds the liner in place for the service life of the liner. Quality of openings for sidelines and junctions and fit at maintenance holes are not to deteriorate over the service life of the liner. Materials Materials to be used are to be nominated in the Contractor’s tender submission. The lining system shall be composed of a material suitable for use in sewerage and stormwater pipelines. It shall be comprised of materials which have an adequate chemical and biologically resistance. The lining shall be resistant to external exposure to soil bacteria and any chemical attack, which may be due to materials in the surrounding ground. Ground conditions to be considered include salt water, acid sulphate soils, stray electrical currents and tree roots amongst others. If requested by the Superintendent, technical data confirming the chemical resistance of the lining or replacement pipe material shall be forwarded by the Contractor. The lining shall be comprised of materials that shall not exceed the allowable limits of shrinkage, thermal contraction, recovery or reversion as detailed elsewhere in this specification and other relevant standards. The lining or replacement pipe material shall have satisfactory abrasion resistance to the migration of silt, sand and debris along the pipe such that the service life of the new pipe is not reduced. It shall be sufficiently robust not to be damaged by pipe cleaning equipment, which may be required to remove any future blockage following installation of the new pipe. If fibreglass reinforced materials are to be used, then the Contractor must first prove to the satisfaction of the Superintendent that the fibreglass liner will not degrade due to wicking at exposed fibres, in particular, at the ends and where service connections are to be cut through. Account shall be taken of the potential defects, which may affect hydraulic performance of the new pipe. New pipe materials should be used which minimise operating costs throughout the life of the asset. Handling The Contractor shall comply with all manufacturers’ recommendations regarding the storage, handling and jointing of materials. All handling, transport and storage shall be undertaken such that no damage or deterioration occurs to the materials including linings and coatings. The Contractor shall reject any damaged or defective material, not use any rejected material in the works and remove any rejected material from the site at the earliest opportunity. Preparation of the Works Other Services Prior to commencement of the Works, the Contractor shall verify locations of all services which may be affected by the construction activities, give notice to all owners concerned and obtain any approvals necessary. The Contractor shall take all actions and provide all things necessary to protect and maintain existing services to the satisfaction of the relevant owner. If a service is damaged, the Contractor shall notify the owner and the Superintendent of all relevant details and arrange for repair in accordance with the owner’s requirements. Notification of acceptance of any repairs by the relevant owner shall be provided to the Superintendent prior to issue of the Certificate of Practical Completion. Cleaning\Pipe Preparation The Contractor is responsible for undertaking a clean-up of the pipes, sidelines, manholes and road gully pits to allow lining, pipe replacement, manhole/pit rehabilitation or CCTV inspection to proceed. As part of that clean-up, it is also the responsibility of the Contractor to use the robotic cutting unit when necessary to achieve a flush, smooth surface along the internal walls of the pipeline enabling the installation of the liner. The robotic cutting unit is to be able to grind/mill various obstructions and defects such as displaced junctions, tree roots or any protuberances. Cleaning shall mean removal and disposal of all foreign matter. All material washed out of the lines is to be trapped in the downstream manhole and removed. This is to be achieved by using the combination high pressure water jet and vacuum unit or other means. Passing of material from manhole section to manhole section shall not be permitted, except where equipment access is not available. Material collected shall be disposed of at approved location as per the Protection of the Environment Operations Act 1997, Protection of the Environment Operations (Waste) Regulation 2005 and additional applicable regulation. The equipment and methods employed shall be appropriate for the Contractor’s particular rehabilitation methods. The Contractor must take all necessary precautions to ensure cleaning operations do not: (a) Damage or flood private/public property (b) Cause a stormwater discharge (c) Damage the stormwater pipe or associated structures The costs of repairing damages shall be borne by the Contractor. CCTV Inspection It is the responsibility of the Contractor to undertake CCTV inspections associated with these works only. This includes CCTV inspections prior, during and post installation. The inspection shall detail the location of junctions and sidelines for later reinstatement by the Contractor. It shall also allow the Contractor to verify that the pipe is sufficiently clear of any debris or other obstruction, which may delay or adversely affect the new pipe. Costs for the CCTV inspections shall be part of the tendered rates submitted by the Contractor. CCTV Inspection Requirements CCTV inspection of conduits shall be conducted in accordance with the Conduit Inspection Reporting Code of Australia WSA 05-2013. The camera, transportation unit, distance measuring devices, illumination systems and ancillary equipment shall be used suitable for the conduit size, material and conditions under which the inspection is undertaken. The camera shall be steerable and be able to negotiate bends within the drainage pipe. A colour camera shall be used which has remotely operated automatic and/or manual adjustment of the focus and iris to allow optimum picture quality to be achieved. The camera lens shall be capable of viewing the extremities of the conduit and panning and or tilting to view the lateral connections and defects or features at and position around the conduit regardless of the direction of travel of the camera in the main conduit. The adjustment of focus and iris shall provide a focal range from 15 mm to infinity. The distance along the conduit in focus from the initial point of observation shall be a minimum of four times the vertical height of the conduit. For circular or regular shaped conduits the camera shall be positioned centrally, ± 10% of the vertical and horizontal diameter, within the conduit. Qualifications of CCTV Operators CCTV operators shall hold a Statement of Attainment in either; NWP331B Inspect conduit and report on condition and features or NWP331A Perform conduit condition evaluation based on WASA05-2013 and recognised qualifications in: Work Health and Safety (General Induction); Traffic