BS-5502-22-1993.pdf

BRITISH STANDARD BS 5502-22: 1993 Buildings and structures for agriculture Part 22: Code of practice for design, construction and loading UDC 631.2:624.04:69.04:72.011 Licensed Copy: sheffieldun sheffieldun, na, Mon Dec 04 14:40:16 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 5502-22:1993 This British Standard, having been prepared under the direction of the Technical Sector Board for Building and Civil Engineering (B/-), was published under the authority of the Standards Board and comes into effect on 15 November 1993 © BSI 12-1998 The following BSI references relate to the work on this standard: Committee reference B/549 Draft for comment 92/19252 DC ISBN 0 580 22181 4 Committees responsible for this British Standard The preparation of this British Standard was entrusted by the Technical Sector Board for Building and Civil Engineering (B/-) to Technical Committee B/549, upon which the following bodies were represented: British Cement Association British Commercial Glasshouse Manufacturers Association British Precast Concrete Federation Ltd. British Veterinary Association Department of Agriculture Northern Ireland Health and Safety Executive Institution of Civil Engineers Local Authority Organizations Ministry of Agriculture, Fisheries and Food National Farmers Union National Rivers Authority Royal Institute of British Architects Royal Institution of Chartered Surveyors Scottish Office (Agriculture and Fisheries Department) Silsoe Research Institute Steel Construction Institute Transport and General Workers Union Water Services Association of England and Wales Amendments issued since publication Amd. No.DateComments Licensed Copy: sheffieldun sheffieldun, na, Mon Dec 04 14:40:16 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 5502-22:1993 © BSI 12-1998i Contents Page Committees responsibleInside front cover Forewordiii 1Scope1 2References1 3Definitions1 4Symbols1 5Preparation of site2 6Service life2 7Foundations2 8Works below ground2 9Works above foundations3 10Protection of floors3 11Protection of walls, piers and columns3 12Protection of roofs3 13Balustrades and safety rails4 14Design classification4 15Loadings5 15.1General5 15.2Wind loads6 15.3Imposed roof loads other than wind loads6 15.4Floor loads7 15.5Wall loads12 15.6Loads on bunkers or clamps for the storage of gross silage12 15.7Loads from bedding material in stock buildings13 15.8Suspended crop loads13 15.9Loads for balustrades and rails13 15.10 Loads on purlins13 16Structural design (materials)13 16.1General13 16.2Structural use of timber14 16.3Structural use of steelwork14 16.4Structural use of concrete15 16.5Use of masonry18 17Structures19 17.1Greenhouses19 17.2Slurry tanks and reception pits19 17.3Tower silos for forage19 17.4Livestock buildings19 17.5Storage, conditioning and processing buildings19 17.6Crop production buildings19 17.7Ancillary buildings19 17.8Cattle grids19 Annex A (normative) Wind loads on tunnel-shaped buildings20 Index22 Licensed Copy: sheffieldun sheffieldun, na, Mon Dec 04 14:40:16 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 5502-22:1993 ii © BSI 12-1998 Page Figure 1 Examples of zone of effect for retaining structures or buildings containing a retaining element5 Figure 2 Components of a typical multi-slat unit8 Figure A.1 Single-span tunnel building20 Figure A.2 Multi-span tunnel building20 Figure A.3 Single-span tunnel building with no eaves21 Figure A.4 Multi-span tunnel building with no eaves22 Table 1 Design classifications4 Table 2 Generalized imposed roof load (altitude less than 100 m with access limited to cleaning and repairs)6 Table 3 Snow load conversion factor v7 Table 4 Characteristic imposed livestock loads for floors capable of lateral distribution of point loads7 Table 5 Characteristic imposed livestock loads for slatted floors9 Table 6 Characteristic imposed vehicle loads for floors9 Table 7 Properties of stored material10 Table 8 Grass silage wall loadings12 Table 9 Crop loads13 Table 10 Horizontal loads for balustrades and handrails13 Table 11 Classification factors13 Table 12 Section properties of timber purlins14 Table 13 Factors for spacing of timber purlins14 Table 14 Load combinations and modified gf values for single storey frames in steel15 Table 15 Load combinations and modified gf values for single storey frames in concrete16 Table 16 Nominal cover to all reinforcement (including links) for a service life of 10 years17 Table 17 Unreinforced concrete made with normal weight aggregates of 20 mm nominal maximum size for a service life of 20 years or less17 Table 18 Nominal concrete cover for plain carbon steel reinforcement in reinforced masonry where the concrete infill has to provide full service life protection18 Table A.1 External pressure coefficients for the end walls of single-span tunnel buildings20 Table A.2 External pressure coefficients for the end walls of multi-span tunnel buildings20 Table A.3 External pressure coefficients for the curved roofs of single-span tunnel buildings with no eaves21 Table A.4 External pressure coefficients for the curved roofs of multi-span tunnel buildings with no eaves at wind direction 90°22 Table A.5 External pressure coefficients for the curved roofs of multi-span tunnel buildings with no eaves at wind direction 90°22 Table A.6 Internal pressure coefficients for single-span and multi-span tunnel buildings22 List of references24 Licensed Copy: sheffieldun sheffieldun, na, Mon Dec 04 14:40:16 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 5502-22:1993 © BSI 12-1998iii Foreword This Part of BS 5502 has been prepared under the direction of the Technical Sector Board for Building and Civil Engineering. It is a revision of BS 5502-22:1987, which is withdrawn. BS 5502 has been restructured into the following broad subject areas: Part 0: Introduction; Parts 10 to 19: Reference information and legislation; Parts 20 to 39: General design; Parts 40 to 59: Livestock buildings; Parts 60 to 79: Crop buildings; Parts 80 to 99: Ancillary buildings. More specifically, the general design series will comprise: Part 20: Code of practice for general design considerations; Part 21: Code of practice for selection and use of construction materials; Part 22: Code of practice for design, construction and loading; Part 23: Code of practice for fire precautions; Part 25: Code of practice for services and facilities; Part 30: Code of practice for control of infestation; Part 31: Code of practice for the management of waste (storage and handling); Part 32: Guide to noise attenuation; Part 33: Guide to control of odour pollution. A more detailed description of the new structure of BS 5502 is given in Part 0. The object of introducing the structure is to allow subject areas to be broadly characterized, and related subject matter, whether in the form of recommendations, guidance or supporting data, to be rationalized and brought together. It will also allow sufficient flexibility to enable BS 5502 to be expanded and developed in a logical way in the future. For design and construction of, and the loadings for, agricultural buildings and structures to be carried out in accordance with this standard, reference has to be made to the relevant material codes of practice, some recommendations of which have been modified by this Part of BS 5502 for classified agricultural buildings and structures. This Part of BS 5502 also contains special considerations peculiar to agricultural buildings and structures that should be taken into account during their design and construction. It has been assumed in the drafting of this Part of BS 5502 that the execution of its provisions is entrusted to appropriately qualified and experienced people, for whose guidance it has been prepared. 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 to iv, pages 1 to 24, 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. Licensed Copy: sheffieldun sheffieldun, na, Mon Dec 04 14:40:16 GMT+00:00 2006, Uncontrolled Copy, (c) BSI iv blank Licensed Copy: sheffieldun sheffieldun, na, Mon Dec 04 14:40:16 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 5502-22:1993 © BSI 12-19981 1 Scope This Part of BS 5502 gives recommendations for the design and construction of, and the loading for, agricultural buildings and structures. 2 References 2.1 Normative references This Part of BS 5502 incorporates, by reference, provisions from specific editions of other publications. These normative references are cited at the appropriate points in the text and the publications are listed on page 28. Subsequent amendments to, or revisions of, any of these publications apply to this British Standard only when incorporated in it by updating or revision. 2.2 Informative references This Part of BS 5502 refers to other publications that provide information or guidance. Editions of these publications current at the time of issue of this standard are listed on the inside back cover, but reference should be made to the latest editions. 3 Definitions For the purposes of this Part of BS 5502, the definitions given in BS 5268-2:1991, BS 5328-1:1991, BS 5628-1:1992, BS 5628-2:1985, BS 5628-3:1985, BS 5950-1:1990, BS 5950-5:1987, BS 6100, BS 7543:1992 and BS 8110-1:1985 apply, together with the following. zone of effect the area around a retaining structure extending a distance 1.5 times its height (h) above ground or its depth (d) below ground, whichever is greater, beyond the retaining structures real or projected ground perimeter 4 Symbols For the purposes of this Part of BS 5502, the following symbols apply: Aaltitude of site in metres above mean sea level; bcbreadth of compression face of a concrete beam (T and inverted L purlins and sheeting rails) measured midway between restraints (see BS 8110-1:1985); btbreadth of tension face of a concrete beam (T and inverted L purlins and sheeting rails) measured midway between restraints (see BS 8110-1:1985); ddepth below ground for zone of effect; dadepth below ground for zone of effect for structures alternative face; E1, E2, E3, E4 classification of exposure situations in accordance with BS 5628-2:1985; GLground level; hheight above ground for zone of effect; haheight above ground for zone of effect for structures alternative face; Hspoint load applied horizontally at the surface of a single slat from livestock (in kN); leeffective length of section; lpspan of a purlin, centre to centre of support (in mm); lseffective span of a multi-slat unit; nnumber of slats in a multi-slat unit; Nreturn period for loading (in years); PBcharacteristic load from bedding (including allowance for livestock) acting horizontally to a wall (in kN/m2); PGconcentrated tractor load on a wall for grass silage (part load) (in kN); PLvertical load on a floor from livestock applied on any square with a 300 mm side (in kN); Psvertical load from livestock applied on a single slat (in kN/m); Pvvertical load on a floor from a vehicle applied on any square with a 300 mm side (in kN); rleast radius of gyration of a section; saltcoefficient used in correcting the basic snow load on the ground for altitude; sbbasic snow load (on the ground); sdsnow load on a roof; sd(N)snow load on a roof with a return period of N years; sosite snow load (on the ground); SC2, SC3, SC4, SC6 strength class of timber as given in BS 5268-2:1991; TGhorizontal load on a wall from grass silage (part load) which increases uniformly with depth z (in kN/m2); vcdesign concrete shear stress as given in BS 8110-1:1985; Licensed Copy: sheffieldun sheffieldun, na, Mon Dec 04 14:40:16 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 5502-22:1993 2 © BSI 12-1998 5 Preparation of site 5.1 For site preparation reference should be made to BS 5930:1981. 5.2 If any drains are severed during the excavations in connection with the building or structure, its drains or services, effective steps should be taken to secure the continued passage of the below-ground water through or around the site and to deal with any surface water which may run on to the site. 6 Service life 6.1 As service life may be different from design life (see BS 7543:1992), where required, guidance should be sought on durability limits of materials. NOTEInformation on predicted service life should be available from the manufacturer or supplier. 6.2 Unless otherwise stated, the structural components and the external envelope should be such that, with reasonable maintenance, they remain effective for the design life. 7 Foundations 7.1 For the design and construction of foundations of a building or structure, reference should be made to BS 8110-1:1985 and BS 8004:1986. Attention should be paid to the possibility of attack by sulfates or any other deleterious matter which may be present in the soil. 7.2 The foundations of a building or structure should: a) safely sustain and transmit to the ground the worst combination of dead load, imposed load and wind load so that it does not cause any settlement or other movement which would impair the stability or serviceability of, or cause damage to, the building or structure or any adjoining building or structure or works; b) be taken down to such a depth, or be so constructed, as to safeguard the building or structure against damage by swelling, shrinkage or freezing of the subsoil; c) be designed to resist overturning moments or sliding forces, especially where lateral imposed loads, induced by the storage of agricultural or other products against walls, are transferred to the foundations. 8 Works below ground 8.1 Ducts, tanks, hoppers and other works below ground should be so designed and built as to resist external ground pressures including, if relevant, the pressure due to the presence of ground water, nearby foundations and other loadings. Where ducts, tanks, etc. are to retain liquids, they should be so constructed as to prevent any contamination by the escape of the liquids into the subsoil and the entry of ground water into the duct, tank or other receptacle. Where tanks are constructed in ground which has a high water table, adequate means of preventing flotation should be provided. 8.2 Covers to ducts, tanks, pits and similar constructions should be provided as necessary. These covers should conform to one of the following: a) be constructed to withstand all loads from livestock, stored materials, the transporting of materials over them, and all vehicles used in the building or structure or its environs; b) be provided with suitable b