BS-8010-2.4-1988.pdf

BRITISH STANDARD BS 8010-2.4: 1988 Code of practice for Pipelines Part 2: Pipelines on land: design, construction and installation Section 2.4 Prestressed concrete pressure pipelines UDC 624.05.005:621.644:621.643.2:666.982.4 Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 01:55:33 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 8010-2.4:1988 This British Standard, having been prepared under the direction of the Civil Engineering and Building Structures Standards Committee, was published under the authority of the Board of BSI and comes into effect on 29 January 1988 © BSI 03-1999 First published, as CP 2010-5, March 1974 First revision, as BS 8010-2.4, January 1988 The following BSI references relate to the work on this standard: Committee reference CSB/10 Draft for comment 85/13185 DC ISBN 0 580 16188 9 Committees responsible for this British Standard The preparation of this British Standard was entrusted by the Civil Engineering and Building Structures Standards Committee (CSB/-) to Technical Committee CSB/10, upon which the following bodies were represented: Association of Consulting Engineers British Compressed Gases Association British Gas plc British Plastics Federation British Precast Concrete Federation Ltd. Concrete Pipe Association Country Landowners Association County Surveyors Society Department of Energy (Petroleum Engineering Division) Ductile Iron Producers Association Electricity Supply Industry in England and Wales Engineering Equipment and Materials Users Association Federation of Civil Engineering Contractors Health and Safety Executive Home Office Institute of Petroleum Institution of Civil Engineers Institution of Gas Engineers Institution of Mechanical Engineers Institution of Public Health Engineers Institution of Water Engineers and Scientists Ministry of Agriculture, Fisheries and Food National Farmers Union Pipeline Industries Guild Royal Institution of Chartered Surveyors Society of British Gas Industries UK Offshore Operators Association Ltd. Water Authorities Association Water Companies Association Water Research Centre Amendments issued since publication Amd. No.Date of issueComments Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 01:55:33 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 8010-2.4:1988 © BSI 03-1999i Contents Page Committees responsibleInside front cover Forewordii Subsection 1. General 1Scope1 2Definitions1 3Application1 4Safety2 5Inspection2 Subsection 2. Materials 6Pipes3 7Fittings and closure units3 8Valves3 9Flanges3 10Bolts, nuts and washers3 11Gaskets and joint rings3 12Materials not complying with British Standards3 Subsection 3. Design considerations 13Pipeline design4 14Pipe design4 15Further design considerations4 16Joint considerations5 17External and internal protection from corrosion5 Subsection 4. Construction 18General8 19Transport, handling and stringing8 20Trenching9 21Pipe inspection and repairs9 22Laying, jointing and anchoring9 23Backfilling10 Subsection 5. Cleaning, testing and commissioning 24Cleaning12 25Testing12 26Commissioning13 Subsection 6. Abandonment 27Disused pipelines14 28Precautions14 29Records14 Appendix A Effect of non-metallic materials on water quality15 Appendix B Bibliography15 Appendix C Information to be supplied with an enquiry or order for cylinder and non-cylinder pipe15 Figure 1 Typical joint detail for non-cylinder prestressed concrete pressure pipes6 Figure 2 Typical joint details for cylinder prestressed concrete pressure pipes (single wound)7 Figure 3 A typical lifting beam suitable for prestressed concrete pressure pipes8 Table 1 Spacing of transverse anchors for steeply inclined pipelines10 Publications referred toInside back cover Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 01:55:33 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 8010-2.4:1988 ii © BSI 03-1999 Foreword This Section of BS 8010 has been prepared under the direction of the Civil Engineering and Building Structures Standards Committee. The standard is being published in four Parts to form a complete revision of all five Parts of CP 2010 as follows: Part 1: Pipelines on land: general; Part 2: Pipelines on land: design, construction and installation; Part 3: Pipelines subsea: design, construction and installation; Part 4: Pipelines on land and subsea: operation and maintenance. The new Part 1 (which will supersede CP 2010-1:1966) is intended to contain general information which is relevant to a variety of pipelines and a variety of transported materials. It deals with those aspects of pipeline development that affect the owner and occupier of land through which the pipeline passes. Part 2 will be divided into several Sections which will be published as separate documents as follows: Section 2.1: Ductile iron; Section 2.2: Steel (for water and associated products); Section 2.3: Asbestos cement; Section 2.4: Prestressed concrete pressure pipelines; Section 2.5: Glass reinforced thermosetting plastic; Section 2.6: Thermoplastics; Section 2.7: Precast concrete; Section 2.8: Steel (for oil, gas and associated products). Each Section will contain information on the design, construction and installation of a pipeline in the particular material. These Sections will supersede Parts 2, 3, 4, and 5 of CP 2010. Part 3 will include information relevant to the design, installation and commissioning of subsea pipelines in steel and other materials. Part 4 will contain advice on the operation and maintenance of pipelines and will probably be in Sections related to the conveyed material. This Section 2.4 supersedes CP 2010-5:1974 which is withdrawn. It deals with pressure pipelines constructed both in cylinder and in non-cylinder prestressed concrete pipes, using pipes and fittings that comply with BS 4625. It has been assumed in the drafting of this British Standard that the execution of its provisions is entrusted to appropriately qualified and experienced people. Attention is drawn to the principal Acts of Parliament enabling pipelines to be constructed and regulating procedures, given in Appendix A of BS 8010-11) A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, pages 1 to 16, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover. 1) In preparation. Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 01:55:33 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 8010-2.4:1988 © BSI 03-19991 Subsection 1. General 1 Scope This Section of BS 8010 gives design considerations and construction and installation recommendations for pressure pipelines incorporating prestressed concrete pipes complying with BS 4625 and should be read in conjunction with BS 8010-12). This British Standard code of practice is not intended to replace or duplicate hydraulic, mechanical or structural design manuals. NOTE 1The numbers in square brackets in the text of this Section refer to the numbered references in Appendix B. NOTE 2The titles of the publications referred to in this standard are listed on the inside back cover. 2 Definitions For the purposes of this Section of BS 8010 the following definitions apply. 2.1 pipeline a line of pipes, of any length, without frequent branches. It does not include piping systems such as process plant piping within refineries, factories or treatment plant 2.2 prestressed concrete cylinder pipe a welded sheet steel cylinder with steel socket and spigot rings welded to its ends, lined with concrete suitably compacted and circumferentially prestressed to withstand internal pressure and external design loads and subsequently coated with cement mortar to protect the steel cylinder and prestressing wires 2.3 prestressed concrete non-cylinder pipe a suitably compacted concrete core longitudinally prestressed with pretensioned high tensile steel wire embedded in the concrete, circumferentially prestressed to withstand internal pressure and external design loads and subsequently coated with cement mortar to protect the circumferential prestressing wire 2.4 working pressure the maximum sustained internal pressure excluding surge to which each portion of the pipeline may be subjected when installed 2.5 works hydrostatic proof test pressure the internal hydrostatic pressure to be applied to every pipe at the manufacturers works 2.6 site test pressure the pressure to be applied to the pipeline, or sections thereof, after laying, to test its strength and watertightness 2.7 surge pressure the maximum and minimum pressure produced by a change in velocity of a moving stream of liquid. It is at its maximum when there is a sudden stoppage such as would be caused by suddenly closing a valve or stopping a pump 2.8 stringing the placing of pipes in line on the ground ready for laying 3 Application The pipelines covered by this Section of BS 8010 are composed of rigid pipes with flexible joints suitable for conveying water, slurries and sludges, sewage, trade wastes and brine under pressure. Prestressed concrete pipes are manufactured to specific lengths and to suit individual requirements but cannot be cut to length on site. Special manufacture is required for closure units. Closures are effected by using closure units which include closure pipes made to the correct length for each situation. Alternatively, for cylinder type pipes only, sized and lined steel closure pipe can be supplied for cutting on site. When used for the conveyance of sewage, reference should be made to CP 20053). The actual service and environmental conditions should be considered in determining whether the pipe is suitable. Service conditions include working pressure, maximum and minimum operating temperatures, the extent of chemical and physical reaction between the material carried and the pipe and joint material, and the toxicity of the material carried. Environmental factors relate to the route of the pipeline and include the amount of open country or built up areas along the route, the nature of the soil, the presence of areas liable to subsidence, the existence of exposed aquifers and any other conditions which might affect the pipeline. 2) In preparation. 3) In course of revision and will be published as BS 8005 . Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 01:55:33 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 8010-2.4:1988 2 © BSI 03-1999 When used under the conditions for which they are designed, materials in contact with or likely to come into contact with potable water should not constitute a toxic hazard, should not support microbial growth and should not give rise to unpleasant taste or odour, cloudiness or discoloration of the water (see Appendix A). 4 Safety 4.1 The recommendations of this Section of BS 8010 are considered to be adequate for public safety under conditions usually encountered in prestressed concrete pipelines. Particular attention is called to the need to prevent damage or leakage arising from: a) excessive settlement, movement or erosion; b) applied external loads; c) mechanical equipment used during construction or on other works; d) aggressive soil conditions. 4.2 Measures to prevent damage may include: a) proper bedding and adequate anchoring to prevent settlement or movement; b) increased earth cover or concrete protection against external damage or erosion; c) indicating the presence of the pipeline with additional markers particularly in congested areas or areas where future development is known to be planned, and adequate marking at river and water course crossings; d) additional protection as recommended in 17.1. 5 Inspection The safety of a properly designed pipeline depends more on the standards and quality of inspection applied at all stages than on any other single feature. Inspection starts at the factory where pipes and components are manufactured and should continue through all stages of construction. Clauses concerning the rights of inspection are given in BS 4625. Any sub-standard materials should be rejected and any faulty workmanship rectified before any further work is done. Particular emphasis should be given to: a) inspection for possible damage to the pipe and any protective coating before installation; b) inspection of trench dimensions; c) inspection of the bedding of the pipeline; d) inspection of jointing; e) inspection of anchoring; f) testing. Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 01:55:33 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 8010-2.4:1988 © BSI 03-19993 Subsection 2. Materials 6 Pipes Prestressed concrete pressure pipes should comply with BS 4625 which specifies two types namely, cylinder and non-cylinder (see 2.2 and 2.3). 7 Fittings and closure units 7.1 Fittings Fittings for use with prestressed concrete pressure pipes should comply with BS 534 or BS 4625. Fittings may be fabricated by welding steel tube or plate or be formed from a prestressed concrete pressure pipe by including additional steel plate or tube where required. 7.2 Closure units Closure units alone or with pipes of non-standard length are required to close gaps between adjacent sections of pipeline. These should be ordered specially to the length required. 8 Valves 8.1 Materials All material used in valves should be compatible with the products which are to be conveyed in the pipeline. Valve bodies should be of ductile iron wherever possible. 8.2 Control valves Valves should comply with an appropriate British Standard specification, the principal ones being: BS 5150, Cast iron wedge and double disk gate valves for general purposes. BS 5152, Cast iron globe and globe stop and check valves for general purposes. BS 5153, Cast iron check valves for general purposes. BS 5155, Cast iron and carbon steel butterfly valves for general purposes. BS 5163, Predominantly key-operated cast iron gate valves for waterworks purposes. It is recommended that the direction of rotation needed to close the valve be clockwise. A clear indication should be given on all valves of the direction of rotation needed to close the valve. The direction of rotation should be the same for any one pipeline installation. 8.3 Air valves Automatic air valves are available in a number of forms, the most common are single orifice, double orifice and kinetic. Reference should be made to the manufacturers recommendations. 9 Flanges Flanges, where used, should comply with BS 4504-1 for steel or