SIST-TP CEN/TR 1295-3:2007

Structural design of buried pipelines under various conditions of loading - Part 3: Common method

This document specifies calculation methods for the structural design of water supply pipelines, drains and sewers, and other water industry pipelines, whether operating at atmospheric, greater or lesser pressure.
It applies for the structural design of buried piping systems, made from all materials used for the conveyance of fluids under pressure or gravity conditions.
Pipes to be designed for installations in abnormal or unusual conditions, e.g. in quick soils or a marine sea bed, are not covered by this document, it may require special engineering.
The design of very large diameter pipe installations may require considerations to be given to other additional parameters, e.g. the homogeneity of the surrounding soil.
The design method is intended to be used for pipes operating at different temperatures provided that the corresponding temperature re-rating factors for the relevant pipe properties are used as specified in the referring standard(s). Nevertheless, high services temperatures may require an additional analysis of the longitudinal stresses and strains and/or a special design of the joints.

Statische Berechnung von erdverlegten Rohrleitungen unter verschiedenen Belastungsbedingungen - Teil 3: Einheitliches Berechnungsverfahren

Calcul de résistance mécanique des canalisations enterrées sous diverses conditions de charge - Partie 3: Méthode commune

Le présent document spécifie les méthodes de calcul pour le calcul de résistance mécanique des conduites d'alimentation en eau, des canalisations d'évacuation et d'assainissement et autres canalisations de l'industrie de l'eau, fonctionnant soit à la pression atmosphérique, soit à des pressions supérieures ou inférieures.
Il s'applique au calcul de résistance mécanique des systèmes de canalisations enterrées, fabriqués à partir de tous les matériaux utilisés pour l'acheminement des fluides, sous pression ou dans des conditions gravitaires.
Les tuyaux devant être calculés pour des installations dans des conditions anormales ou inhabituelles, par exemple dans des sols boulants ou sous la mer, ne sont pas couverts par le présent document et l'utilisation d'une étude spéciale peut s'avérer indispensable.
Le calcul d'installations de tuyaux de très gros diamètres peut exiger la prise en compte d'autres paramètres additionnels, comme par exemple l'homogénéité du sol environnant.
La méthode de conception est censée être employée pour des tuyaux exploités à différentes températures à condition que les coefficients correspondants de réévaluation de la température pour les propriétés concernées du tuyau soient utilisés de la manière spécifiée dans la (les) norme(s) de référence. Néanmoins, les températures de service élevées peuvent exiger une analyse complémentaire des contraintes et des déformations longitudinales et/ou une conception spéciale des assemblages.

Projektiranje vkopanih cevovodov pri različnih pogojih obtežb - 3. del: Skupna metoda

General Information

• Status: Published
• Publication Date: 09-Sep-2007
• ICS: 23.040.01 - Pipeline components and pipelines in general
• Technical Committee: IOVO - Water supply and waste water engineering
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 03-Sep-2007
• Due Date: 08-Nov-2007
• Completion Date: 10-Sep-2007
• Ref Project: CEN/TR 1295-3:2007 - Structural design of buried pipelines under various conditions of loading - Part 3: Common method

Standards Content (Sample)

SLOVENSKI STANDARD
SIST-TP CEN/TR 1295-3:2007
01-oktober-2007
3URMHNWLUDQMHYNRSDQLKFHYRYRGRYSULUD]OLþQLKSRJRMLKREWHåEGHO6NXSQD
PHWRGD
Structural design of buried pipelines under various conditions of loading - Part 3:
Common method
Statische Berechnung von erdverlegten Rohrleitungen unter verschiedenen
Belastungsbedingungen - Teil 3: Einheitliches Berechnungsverfahren
Calcul de résistance mécanique des canalisations enterrées sous diverses conditions de
charge - Partie 3: Méthode commune
Ta slovenski standard je istoveten z: CEN/TR 1295-3:2007
ICS:
23.040.01 Deli cevovodov in cevovodi Pipeline components and
na splošno pipelines in general
SIST-TP CEN/TR 1295-3:2007 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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TECHNICAL REPORT
CEN/TR 1295-3
RAPPORT TECHNIQUE
TECHNISCHER BERICHT
July 2007
ICS 23.040.01

English Version
Structural design of buried pipelines under various conditions of
loading - Part 3: Common method
Calcul de résistance mécanique des canalisations Statische Berechnung von erdverlegten Rohrleitungen
enterrées sous diverses conditions de charge - Partie 3: unter verschiedenen Belastungsbedingungen - Teil 3:
Méthode commune Einheitliches Berechnungsverfahren
This Technical Report was approved by CEN on 11 July 2005. It has been drawn up by the Technical Committee CEN/TC 165.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,
Romania, 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
© 2007 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN/TR 1295-3:2007: E
worldwide for CEN national Members.

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CEN/TR 1295-3:2007 (E)
Contents Page
Foreword.6
Introduction .7
1 Scope .9
2 References.9
3 Structural design issues .9
3.1 Soils .9
3.2 Pipe materials.11
3.3 Types of loading .11
3.3.1 Soil load .11
3.3.2 Traffic load.11
3.3.3 Groundwater.11
3.3.4 Installation loads.11
3.3.5 Internal pressure.11
3.3.6 Pipes own weight.12
3.3.7 Weight of fluid.12
3.3.8 Subsidence (differential settlement).12
3.3.9 Temperature differences.12
3.3.10 Landslide .12
3.3.11 Loading by earthquake .12
4 Principles used in Annex A (Option 1) and Annex B (Option 2) .13
4.1 General.13
4.2 Principles used in Annex A (Option 1) .13
4.2.1 Introduction.13
4.2.2 Information on the content of Annex A (Option 1).13
4.3 Principles used in Annex B (Option 2) .16
5 Synopsis .18
Annex A Structural design of buried pipelines - Option 1.21
A.1 General.21
A.2 Terms and definitions .21
A.3 Symbols .25
A.4 Principle.31
A.5 Installation conditions.33
A.5.1 Geometric parameters.33
A.5.2 Construction procedures.33
A.5.3 Influencing parameters .34
A.5.4 Selection of embedment type.35
A.6 Initial loads .39
A.6.1 Soil load .39
A.6.2 Surface loads .41
A.6.3 Traffic loads.43
A.6.4 Seismic actions.47
A.6.5 Other loads .48
A.7 Soil parameters.48
A.7.1 Soil groups .48
A.7.2 Soil properties.48
A.7.3 Soil pressure ratio .54
A.8 Load distributions.55
A.8.1 General.55
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CEN/TR 1295-3:2007 (E)
A.8.2 Distribution in circumferential direction.56
A.8.3 Load concentration factors .62
A.9 Loads acting on the pipe .68
A.9.1 General .68
A.9.2 Vertical direction .69
A.9.3 Horizontal direction.70
A.10 Internal pressure .75
A.10.1 General .75
A.10.2 Internal working pressure.75
A.10.3 Internal surge pressure.75
A.11 Pipe deflection .76
A.11.1 General .76
A.11.2 Vertical deflection.76
A.11.3 Horizontal deflection .79
A.12 Analysis of bending moments, normal forces, stresses and strains .80
A.12.1 General .80
A.12.2 Bending moments and normal forces.80
A.12.3 Stresses and/or strains.85
A.13 Longitudinal effects .95
A.14 Stability analysis (only required for flexible pipes) .95
A.14.1 Imperfections .95
A.14.2 Stability analysis with buckling and snap through loads .96
A.15 Calculated factors of safety from the design procedure and analysis.100
A.15.1 General .100
A.15.2 Circumferential direction.100
A.15.3 Longitudinal direction.103
A.16 Minimum factors of safety and failure probability .103
A.16.1 Principles.103
A.16.2 Safety factors against load bearing failure.103
A.16.3 Safety against inadmissible large deflections .104
A.16.4 Safety against failure in case of not predominantly static load .104
Annex AA Classification of soils .105
Annex AB Factors of safety and failure probability.106
Annex AC Soil mechanics background on soil moduli.107
Annex AD General remarks on stability analyses for buried pipes .110
Annex AE Finite element analysis .112
Annex AF Detailed notes relative to longitudinal effects.113
Annex AG Flowchart and worked examples.114
Annex B Structural design of buried pipelines - Option 2 .128
B.1 General .128
B.2 Terms and definitions .128
B.3 Symbols.131
B.4 Principle.134
B.5 Pipe parameters.135
B.5.1 Dimensions .135
B.5.2 Elastic properties .135
B.5.3 Pipe ring stiffness .135
B.5.4 Pipe characteristics figures .136
B.6 Installation conditions and related calculation parameters.136
B.6.1 Introduction.136
B.6.2 Soil classification .137
B.6.3 Embedments and beddings.137
B.6.4 Compaction.138
B.6.5 Calculation parameters.140
B.7 Stiffness criterion .143
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CEN/TR 1295-3:2007 (E)
B.8 Loadings .143
B.8.1 General.143
B.8.2 Soil vertical pressure due to fill .144
B.8.3 Vertical pressure due to service loads.147
B.8.4 Total vertical pressure p (due to fill and service loads) .149
v
B.8.5 Horizontal pressure p due to fill and service loads .149
h
B.8.6 Pressure due to external water pressure p .149
we
B.8.7 Action due to self weight .149
B.8.8 Force due to water weight .149
B.9 Load and interaction pressure distributions .149
B.9.1 General.149
B.9.2 Loads distribution.150
B.10 Buckling.151
B.11 Ring deflection.152
B.12 Bending moments, axial forces, stresses and strains.153
B.12.1 Bending moments.153
B.12.2 Axial forces.154
B.12.3 Strains.154
B.12.4 Stresses .154
B.13 Verification of safety in use .155
B.13.1 Definition of the limit states.155
B.13.2 Verification with respect to ultimate limit state .156
B.13.3 Verification with respect to serviceability limit states.158
B.13.4 Verification with respect to fatigue.159
B.13.5 Verification for pressure pipes.159
B.14 Summary of design procedures and relevant verifications .161
B.14.1 Choice of parameters used in the design method .161
B.14.2 Calculation of the actions .162
B.14.3 Calculation of the loads and deflections.163
B.15 Analysis of longitudinal effects.164
B.16 Analysis of seismic action.164
Annex BA Classification of soils.165
Annex BB Factors of safety and failure probability.166
Annex BC Background on soil moduli .167
Annex BD Rigid, semi-rigid and flexible pipes — A proposal for a definition of ranges of system
behaviour.168
Annex BE Background of the Marston method.175
Annex BF Longitudinal effects — Notes of B.15 .183
Annex BG Worked examples.184
Annex C Classification of soils .190
Annex D Factors of safety and failure probability.193
D.1 Rudiments of the theory of probabilistic reliability.193
D.2 Analysis of reliability of buried piping systems.196
D.3 Scatter of parameters.196
D.4 Results of the analysis.196
Annex E Longitudinal effects .197
E.1 Longitudinal effects.197
E.2 Failure behaviour due to longitudinal effects.197
E.3 Failure modes.197
E.3.1 General.197
E.3.2 Pipeline failure .198
E.3.3 Joint failure.198
E.3.4 Gradient loss.198
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CEN/TR 1295-3:2007 (E)
E.4 Longitudinal effects .198
E.4.1 Genral .198
E.4.2 Discontinuous support .199
E.4.3 Directional changes .199
E.4.4 Pressure loading .199
E.4.5 Temperature differences.199
E.4.6 Settlements and subsidence.200
E.4.7 Transition zones .201
Annex F Detailed notes relative to longitudinal effects (according to A.13 and B.15).202
Bibliography.205

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CEN/TR 1295-3:2007 (E)
Foreword
This document (CEN/TR 1295-3:2007) has been prepared by Technical Committee CEN/TC 165
“Wastewater engineering”, the secretariat of which is held by DIN.
This document has been prepared by a joint working group of the Technical Committee CEN/TC 165
“Wastewater engineering” the secretariat of which is held by DIN and the Technical Committee CEN/TC 164
"Water supply", the secretariat of which is held by AFNOR.
This document is a composition of two options for the structural design of buried pipelines, including the
annexes of each option, which have been combined in one single document. The document includes therefore
the followind Annexes:
Annex A , Structural design of buried pipelines – option 1, including the Annexes to option 1 (Annex AA to
Annex AG);
Annex B, Structural design of buried pipelines – option 2, including the Annexes to option 2 (Annex BA to
Annex BG);
Annex C , Classification of soils;
Annex D, Factors of safety and failure probability;
Annex E, Longitudinal effects;
Annex F, Detailed notes relative to longitudinal effects.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.

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CEN/TR 1295-3:2007 (E)
Introduction
The history
In the mid-eighties the European Commission gave CEN an Order Voucher to develop a so-called "Common
Structural Design Method for Buried Pipes" and the work was allocated jointly to CEN/TC 164 (Water supply)
and CEN/TC 165 (Waste water engineering). To avoid duplication of work a Joint Working Group (CEN/TC
164/165 JWG1) was created in 1990. As a first step the group produced EN 1295-1, which was published in
July 1997 and is a general part describing the "principles and input parameters" for structural design of buried
pipelines and gives guidance on the application of these principles to nationally established methods of
design. Reference was made to those methods and sources of information on them are given.
The second step was to produce CEN/TR 1295-2, which was published in August 2005 and describes
national or regional methods JWG1 continued its work with the aim of developing a single method for the
structural design of buried pipes for water and wastewater, planned as EN 1295-3 (WI 00165155).
NOTE The work on WI 00165155 concentrated on pipes, not the piping system involving all components.
In 199
...