1、BRITISH STANDARD BS 1722-4: 1986 Incorporating Amendment No. 1 Fences Part 4: Specification for cleft chestnut pale fences UDC 692.88+674.26+677.533BS 1722-4:1986 This British Standard, having been prepared under the directionof the Road EngineeringStandards Committee, was published underthe authori
2、ty of the BoardofBSI and comes into effecton 31 December1986 BSI 07-1999 First published March 1950 First revision April 1963 Second revision July 1972 Third revision December 1986 The following BSI references relate to the work on this standard: Committee reference RDB/34 Draft for comment 84/11286
3、 DC ISBN 0 580 15506 4 Committees responsible for this British Standard The preparation of this British Standard was entrusted by the Road Engineering Standards Committee (RDB/-) to Technical Committee RDB/34, upon which the following bodies were represented: British Independent Steel Producers Asso
4、ciation British Precast Concrete Federation Ltd British Steel Industry British Steel Industry (Wire Section) British Timber Merchants Association British Wire Netting Association British Wood Preserving Association Cement and Concrete Association Concrete Society Country Landowners Association Depar
5、tment of Agriculture and Fisheries for Scotland Department of the Environment (Building Research Establishment, Princes Risborough Laboratory) Department of the Environment (Property Services Agency) Department of Transport (Highways) Fencing Contractors Association Forestry Commission Home Timber M
6、erchants Association of Scotland Institute of Clerks of Works of Great Britain Inc. Institute of Leisure and Amenity Management Landscape Institute Ministry of Agriculture, Fisheries and Food National Council of Building Materials Producers National Farmers Union Royal Institution of Chartered Surve
7、yors Society of Chain Link Fencing Manufacturers Society of Chestnut Fencing Manufacturers Timber Growers United Kingdom Timber Research and Development Association Timber Trade Federation Wire Products Association The following bodies were also represented in the drafting of the standard, through s
8、ub-committees and panels: Cold Rolled Sections Association Consumer Standards Advisory Committee of BSI County Surveyors Society Fencing Industry Association Amendments issued since publication Amd. No. Date of issue Comments 6782 December 1991 Indicated by a sideline in the marginBS 1722-4:1986 BSI
9、 07-1999 i Contents Page Committees responsible Inside front cover Foreword ii Section 1. General 1.1 Scope 1 1.2 Definitions 1 1.3 Dimensions and general characteristics 1 Section 2. Materials 2.1 Wire 2 2.2 Concrete components 2 2.3 Timber components 3 2.4 Fittings 3 2.5 Concrete surrounding bases
10、 of posts and struts 3 Section 3. Erection 3.1 Level 5 3.2 Posts and struts 5 3.3 Infill 5 Appendix A Concrete components 6 Appendix B Specifying a cleft chestnut pale fence 7 Table 1 General characteristics of cleft chestnut pale fences 1 Table 2 Concrete fence posts and struts 2 Table 3 Timber fen
11、ce posts and struts 4 Publications referred to Inside back coverBS1722-4:1986 ii BSI 07-1999 Foreword This British Standard has been prepared under the direction of the Road Engineering Standards Committee. It is a revision of BS1722-4:1972, which is withdrawn. BS 1722 is published in separate Parts
12、 as follows: Part 1: Specification for chain link fences; Part 2: Specification for rectangular wire mesh and hexagonal wire netting fences; Part 3: Specification for strained wire fences; Part 4: Specification for cleft chestnut pale fences; Part 5: Specification for close boarded fences; Part 6: S
13、pecification for wooden palisade fences; Part 7: Specification for wooden post and rail fences; Part 8: Specification for mild steel (low carbon steel) continuous bar fences; Part 9: Specification for mild steel (low carbon steel) fences with round or square verticals and flat posts and horizontals;
14、 Part 10: Specification for anti-intruder fences in chain link and welded mesh; Part 11: Specification for woven wood and lap boarded panel fences; Part 12: Specification for steel palisade fences; Part 13: Specification for chain link fencing for tennis court surrounds. The various Parts specify re
15、quirements for the types of fence that are considered suitable for standardization. It should be noted that no attempt has been made to standardize fences or gates of a purely decorative nature, to suit special requirements, or to specify requirements for “patent” proprietory fencing systems. It is
16、recommended that the structure of such fences or gates should comply with those parts of this Part of BS1722 that are applicable. 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. The purp
17、ose of this standard is to establish minimum requirements for materials and workmanship for the more common types of fence in order to ensure satisfactory service for the purchaser, and to assist manufacturers and erecting contractors by eliminating unnecessary minor variations in the demands of pur
18、chasers. It specifies requirements for the components that make up a fence and the way in which the fence needs to be constructed. Throughout this standard there are requirements for sizes of components, together with the permissible tolerances on size. These are minimum requirements and it will nor
19、mally be acceptable to use larger sizes, except where it would otherwise adversely affect the fit of components or where replacement parts need to match up with those already present. The choice of a fence is affected by factors such as the intended purpose of the fence, the desired service life, ae
20、sthetic considerations and the availability of components. The specifier of the fence will know its intended purpose and by reference to Table 1 a suitable choice can be made. This then gives those erecting the fence the basic characteristics that need to be provided. This standard does not specify
21、any protective treatments. Premature failure can be avoided by taking care not to damage protective treatments during installation. Ground conditions may indicate that a variation in the length of a post or strut, or of the depth to which it should be set, is desirable. The posts and struts and sett
22、ing depths specified in this standard are intended for use in normal ground but if special conditions exist that warrant a change in the specification, e.g.ground that is softer or firmer than usual, such a change needs to be agreed with the specifier, as for other variations.BS 1722-4:1986 BSI 07-1
23、999 iii To assist those specifying and/or providing a fence, Appendix B provides guidance on the more important details, which often take the form of selected options, that need to be specified at the time of ordering a fence. This is a new feature of the standard. This revision has retained the met
24、hod of allocating a reference code to each type of fence, indicating its height and the material used for the posts. These type references are given in full in Table 1. The first two letters indicate the material of the post, and the numbers give an indication of the height of the fence. The third l
25、etter, where present, indicates a particular spacing of the pales, e.g.CW105B indicates a1.05m high fence on timber posts with a pale spacing of100mm. For the sake of uniformity the quoted heights are those of the main infill material and exclude any ground clearance at the base. Designations of bol
26、t size are in accordance with BS4190. The proof test of concrete strength has been deleted as experience has shown that there are technical problems associated with the application and interpretation of the test. Cube tests of concrete strength are now required and the frequency of testing is specif
27、ied to ensure that regular quality checks are made. 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 ob
28、ligations. Summary of pages This document comprises a front cover, an inside front cover, pagesito iv, pages1to8, 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
29、inside front cover.iv blank BSI 07-1999 1 BS 1722-4:1986 Section 1. General 1.1 Scope This Part of BS1722 specifies requirements for cleft chestnut pale fences. This standard specifies lengths of posts and struts, and foundation details for use in normal ground and does not cover the situations wher
30、e special conditions exist, e.g.ground that is softer or firmer than usual, which warrant a change in normal lengths (see foreword). This standard is divided into sections that specify separate requirements for the material components for fences (seesection2) and the erection of the fences (seesecti
31、on3). NOTEThe titles of the publications referred to in this standard are listed on the inside back cover. 1.2 Definitions For the purposes of this Part of BS1722 the timber definitions in BS6100-4.1 apply together with the following. sectored a section formed by longitudinal sawing of a natural rou
32、nd so that one part of the original perimeter is present on the final section 1.3 Dimensions and general characteristics The dimensions of cleft chestnut pale fences, except for the spacing between lines of wiring, shall be as given in Table 1. NOTEIt is recommended that the spacing between lines of
33、 wiring is as given in Table 1. Table 1 General characteristics of cleft chestnut pale fences Fence types a Lengt h of pales Applicability Number of lines of wiring Approximate spacing between lines of wiring b Spacing between pales Maximum distance between intermediate concrete posts Maximum distan
34、ce between intermediate wooden posts With concrete posts With wooden posts CC 90 CW 90 m 0.90 Housing 2 mm 600 mm 75 m 3.0 m 2.50 CC 105A CC 105B CW 105A CC 105B 1.05 Housing and inner fences of parks etc. Miscellaneous 750 75 100 CC 120 CW 120 1.20 General purposes 3 450 75 2.75 2.25 CC 135 CW 135
35、1.35 Road boundaries 525 CC 150 CW 150 1.50 Outer fences of parks and other boundaries 600 50 2.25 2.0 CC 180 CW 180 1.80 Factories and security 750 a These reference codes are included as a guide for use when specifying a fence (see foreword). b Top and bottom wires approximately 150 mm from the en
36、d of the pales.BS1722-4:1986 2 BSI 07-1999 Section 2. Materials 2.1 Wire 2.1.1 General All wire shall comply with BS4102. 2.1.2 Wiring The wire for securing pales shall be zinc coated low carbon steel wire with a nominal diameter of not less than1.9mm. Each line of wiring shall consist of four wires
37、 twisted together between the pales. (Seealso2.3.3.) 2.1.3 Stirrup wire Stirrup wire shall be zinc coated low carbon steel and shall have a nominal wire diameter of2.5mm. 2.1.4 Barbed wire Barbed wire shall be zinc coated low carbon steel or high tensile steel wire. 2.2 Concrete components 2.2.1 Gen
38、eral 2.2.1.1 Material. Concrete posts and struts shall be of steel reinforced concrete in accordance with Appendix A. 2.2.1.2 Tolerances on size. The following permissible deviations shall apply to the specified size of concrete components when determining the actual sizes. a) A demoulding draw allo
39、wance of up to4mm on each of two opposing sides. b) An allowance on the base dimensions of intermediate posts resulting from the use of a mould having the base dimensions given in Table 2 that has been shortened by means of a stopping-off plate located not more than 300mm from the base of the mould.
40、 c) Additional deviations on size of: 1) length:mm; 2) cross section:mm. NOTEThe cross secton is measured about the centre lines. 2.2.1.3 General constructional details. The long arrises formed in the mould shall either be rounded or have all sharp edges removed. The heads of posts shall be weathere
41、d or half rounded so as to prevent lodgement of water. Holes for bolts shall allow the bolt to be freely inserted. Holes for wire shall allow an M6 bolt to be freely inserted. All holes shall be free from obstructions and shall be accurately positioned. 2.2.2 Posts and struts 2.2.2.1 Fence posts and
42、 struts. The dimensions of concrete fence posts and struts shall be as given inTable 2, except that if barbed wire is to be fixed above the fencing, the length of the posts shall be increased by150mm for each line of barbed wire. Fence posts and struts shall be reinforced with four steel reinforcing
43、 bars of the size given inTable 2 except that if steel having a characteristic strength greater than250N/mm 2is used, the cross section of the reinforcing bars shall be either as given in Table 2 or proportionately reduced. Straining posts and struts shall not be tapered. Straining posts shall be pr
44、ovided with a firm bearing for struts at a point within the top third of the length of the straining post measured above the ground level. Straining posts shall be holed for the attachment of eye bolt strainers. Table 2 Concrete fence posts and struts +50 25 +6 4 Fence height Intermediate posts Stra
45、ining posts Struts Length ab Base dimension c Reinforcement diameter (all lengths) Length ab Section Reinforcement diameter Length d Section Reinforcement diameter (all lengths) m m mm mm m mm mm m mm mm 0.90 1.57 100 100 6 1.57 100 100 6 1.50 75 75 6 1.05 1.72 1.72 1.65 1.20 1.35 1.87 2.02 125 125
46、1.87 2.02 125 125 8 1.83 1.98 100 75 1.50 1.80 2.32 2.62 2.32 2.62 2.29 2.59 100 85 a The lengths of posts specified in this table are for normal ground and are appropriate when the top line of wiring is 225 mm from the top of the post. It is essential that this distance is not less than75 mm. The l
47、ength of post should be adjusted to maintain the embedded length (see1.1). b If barbed wire is to be fixed above the fencing, the length of the post is increased by150 mm for each line of barbed wire. c Reducing to75mm 75mm at the top. d These lengths are suitable for struts fixed at an angle of45 o
48、n level ground. If site conditions make the use of struts of these lengths unsuitable, a different length may need to be specified (see1.1).BS 1722-4:1986 BSI 07-1999 3 Intermediate posts shall be tapered to75mm 75mm at the top and shall be holed to allow the attachment of wires. 2.3 Timber componen
49、ts 2.3.1 General 2.3.1.1 Material. Timber shall be of round, cleft or sectored sweet chestnut, shall be entirely free from active insect attack and all forms of rot, dote and deadwood, and shall be shaved clear of bark and underrind. For posts, a straight line from the centre of the butt to the centre of the top shall pass within the circumference of the component for the full length. Any bow shall be in not more than one plane and one direction. 2.3.1.2 Tolerances on size. The following permissible deviations shall appl
