NF-EN-13480-6-A1-2005-ENG.pdf

EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM EN 13480-6:2004/A1 December 2005 ICS 23.040.01 English Version Metallic industrial piping - Part 6: Additional requirements for buried piping Tuyauteries industrielles métalliques - Partie 6 : Exigences complémentaires relatives aux tuyauteries enterrées Metallische industrielle Rohrleitungen - Teil 6: Zusätzliche Anforderungen an erdgedeckte Rohrleitungen This amendment A1 modifies the European Standard EN 13480-6:2004; it was approved by CEN on 22 September 2005. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for inclusion of this amendment into the relevant national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CEN member. This amendment exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMITÉ EUROPÉEN DE NORMALISATION EUROPÄISCHES KOMITEE FÜR NORMUNG Management Centre: rue de Stassart, 36 B-1050 Brussels © 2005 CENAll rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 13480-6:2004/A1:2005: E EN 13480-6:2004/A1:2005 (E) 2 Contents Page Foreword 3 5 Design and calculation.4 5.2 Design4 Annex A (normative) Calculations for buried piping.5 A.1 General 5 A.2 Materials 5 A.3 Design and calculation.5 A.3.1 Calculation procedure 5 A.3.2 Determination of the loads due to backfill5 A.3.3 Determination of the loads due to live loads17 A.3.4 Determination of the moments acting upon the piping .21 A.3.5 Global stability of a buried piping system 23 Annex ZA (informative) Relationship between this European Standard and the Essential Requirements of EU Directive 97/23/EC28 EN 13480-6:2004/A1:2005 (E) 3 Foreword This European Standard (EN 13480-6:2004/A1:2005) has been prepared by Technical Committee CEN/TC 267 “Industrial piping and pipelines”, the secretariat of which is held by AFNOR. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by June 2006, and conflicting national standards shall be withdrawn at the latest by June 2006. This European Standard has been prepared under a mandate given to CEN by the European Commission and the European Free Trade Association, and supports essential requirements of EU Directive(s). For relationship with EU Directive(s), see informative Annex ZA, which is an integral part of this European Standard. This European Standard contains the Annex A (normative) to be added in EN 13480-6:2004, and the Annex ZA updated to replace the current Annex ZA in EN 13480-6:2004. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EN 13480-6:2004/A1:2005 (E) 4 5 Design and calculation Replace title of 5.2 by: 5.2 Design Replace 5.2.5 by: 5.2.5 Where no detailed analysis is undertaken, the maximum temperature range (including the installation temperature) shall not exceed 35 °C, and restraining features such as buried bends and tees shall have a separation of not less than 5 DN. Where detailed analysis is undertaken, it shall be in accordance with EN 13480-3 supplemented by Annex A (normative). EN 13480-6:2004/A1:2005 (E) 5 Annex A (normative) Calculations for buried piping A.1 General This annex describes the applicable requirements for buried piping, supplementing those of EN 13480-3 and EN 13480-6. Thus, it is proposed to deal with the calculations for buried piping taking account of the following: weight of the soil or backfill above the pipe according to the different types of installation; static and dynamic loads imposed on the ground above the pipe (e.g. traffic loads); flexibility and stability of the piping subjected to combined pressure and temperature change effects. A.2 Materials The requirements specified in EN 13480-2 apply without any restriction. However, one shall remind that the corrosion phenomena occurring in the case of buried piping may be significantly different from those to which piping above-ground, in ducts or tunnels are subjected. A.3 Design and calculation A.3.1 Calculation procedure a) Determination of the required thicknesses from the equations given in EN 13480-3 when the piping is subjected only to internal pressure; b) determination of the loads due to backfill (A.3.2) and to live loads (A.3.3); c) checking of the thicknesses defined in a) for the different operating conditions under which the loads defined in b) are applicable (A.3.4); d) checking of the global stability of the buried piping system. A.3.2 Determination of the loads due to backfill A.3.2.1 General The installation methods for buried piping covered are as follows: piping in narrow trench; piping in wide trench or in positive projecting embankment condition. EN 13480-6:2004/A1:2005 (E) 6 A.3.2.2 Notations For the purposes of this annex the following notations shall apply: Ctass = Settlement ratio (see A.3.2.5.1 b); Cdyn = Coefficient for taking into account the dynamic effect of the live loads; Do = External piping diameter. For standardized tubes, Do is the theoretical external diameter, tolerances excluded; eord = Ordered wall thickness; Et = Backfill material modulus; E = Modulus of elasticity for the piping material (see EN 13480-3); Ht = Total height from the top of the piping to natural ground surface (cover); He = Distance from the plane of equal settlement to the top of pipe; k = Ratio of lateral pressure to vertical pressure for the backfill material (Rankine coefficient): 2 24 tan = k Lt = Width of the trench in the horizontal plane containing the top of the piping; t = Unit weight of backfill material; = Angle of internal friction for the material used to fill the trench; µ = Coefficient of internal friction of backfill material; µ' = Coefficient of sliding friction between the backfill material and the trench walls; µ' is always less than or equal to µ and µ' may be taken as µ provided that backfilling material of proper quality (homogeneity) is used; F = Load per unit length. A.3.2.3 Soil properties In the absence of specific data, the values given in the table hereafter may be used for the design and calculation of buried piping. EN 13480-6:2004/A1:2005 (E) 7 Table A.3.2.3 Soil properties and backfill material Type of soil Density µ = tan () k µ' = tan (')k µ k µ' daN/m3 ° Topsoil a 1 450 22 0,404 0,184 0,184 Partially compacted (moist) topsoil b 1 440 0,330 0,500 0,165 Saturated topsoil b 1 760 0,370 0,400 0,150 Sandy clay c 25 0,406 Clay c 22 Silty clay a 2 000 20 0,364 0,178 0,178 Plastic clay Sandy clay a 1 800 14 0,249 0,152 0,152 Moist clay a 2 000 12 0,213 0,139 0,139 Yellow clay, moist and partially compacted b 1 600 0,330 0,400 0,130 Saturated yellow clay or loam b 2 080 0,370 0,300 0,110 Coarse gravely sand c 43 Medium sand c 40 Fine sand c 38 Silty sand c 36 Uncompacted sand a 1 700 31 0,601 0,192 0,192 Sand - Gravel a 2 000 33 0,649 0,191 0,191 Clayey sand a 1 800 22 0,404 0,184 0,184 Saturated clayey sand b 2 110 0,350 0,400 0,140 Dry sand b 1 600 0,330 0,500 0,165 Moist sand b 1 920 0,330 0,500 0,165 Sludge c 18 Marshy ground Peat a 1 700 12 0,213 0,139 0,139 (Continued) EN 13480-6:2004/A1:2005 (E) 8 Table A.3.2.3 (concluded) Type of soil Density µ = tan () k µ' = tan (')k µ k µ' daN/m3 ° Loamy loess (alluvial deposits) a 2 100 18 0,325 0,172 0,172 Loam Marl poor clay a 2 100 22 0,404 0,184 0,184 Sandy silt a 1 800 25 0,466 0,189 0,189 Gravel Pebbles a 1 900 37 0,754 0,187 0,187 Loose gravelly backfilling material b 1 700 0,330 0,580 0,192 Stony-sandy backfilling material b 1 900 0,330 0,500 0,165 Moist-loamy backfilling material b 2 000 0,330 0,450 0,150 a Calcul des sollicitations extérieures agissant sur les conduites enterrées (Calculation of external loadings acting on buried pipings) - CERIB 1970. b The theory of external loads on closed conduits in the light of the latest experiments - MARSTON 1930. c Stabilité des canalisations enterrées (Stability of buried pipelines) - E.M.YASSINE et V.I. TCHERNIKINE - Moscow 1968. A.3.2.4 Piping in narrow-trench condition A.3.2.4.1 Definition A piping is considered as piping in narrow-trench condition (Figures A.3.2.4.1-1 to A.3.2.4.1-4) if one of the following conditions is satisfied: 0 D Lt 0 12 2 2 += + tassr o eo e eCqk D Hk D Hk µ µ µ (A.3.2.5.1-2) Ctass Ht: virtual plane of equal settlement Ctass 0 t o o t e H D k C D Hk µ µ 2 1 2 2 + = + (A.3.2.5.2-2) Ctass 0 + + + + = o e o e e e t e t o ' D Hk D Hk H H H D k C µ µ µ 2 2 2 1 2 1 (A.3.2.5.2-4) Ctass L. EN 13480-6:2004/A1:2005 (E) 28 Annex ZA (informative) Relationship between this European Standard and the Essential Requirements of EU Directive 97/23/EC This European Standard has been prepared under a mandate given to CEN by the European Commission to provide a means of conforming to Essential Requirements of the New Approach Directive 97/23/EC. Once this European Standard is cited in the Official Journal of the European Communities under that Directive and has been implemented as a national standard in at least one Member State, compliance with the clauses of this European Standard given in Table ZA.1 confers, within the limits of the scope of this European Standard, a presumption of conformity with the corresponding Essential Requirements of that Directive and associated EFTA regulations. Table ZA.1 Correspondence between this European Standard and Directive 97/23/EC Clause(s)/sub- clause(s) of this EN s Essential Requirements (ERs) of Directive 97/23/EC Qualifying remarks/Notes 3.1 to 3.3 2 Design 3.1 b) and 7 6 (a) and 6 (g) Piping as referred to in article 3, section 1.3 4 4.1 Material 5.1 2.2 Design for adequate strength 5.2 2.2.3 b) Calculation method 8.1 to 8.3 2.6 Corrosion 9 3.2.1 and 3.2.2 Final inspection and proof test Annex A 2.2.3 Calculation method WARNING Other requirements and other EU Directives may be applicable to the product(s) falling within the scope of this European Standard.