kSIST FprEN 1993-1-6:2024

Eurocode 3 - Design of steel structures - Part 1-6: Strength and Stability of Shell Structures

1.1   Scope of EN 1993-1-6
(1) EN 1993-1-6 provides rules for the structural design of plated steel structures that have the form of a shell of revolution (axisymmetric shell).
(2) This document is applicable to unstiffened fabricated axisymmetric shells formed from isotropic rolled plates using both algebraic and computational procedures, and to stiffened axisymmetric shells with different wall constructions using computational procedures. It also applies to associated circular or annular plates and to beam section rings and stringer stiffeners where they form part of the complete shell structure. The general computational procedures are applicable to all shell forms.
(3) This document does not apply to manufactured shells or to shell panels or to elliptical shell forms, except that its computational procedures are applicable to all shell structures. This document does not apply to structures under seismic or other dynamic loading. It does not cover the aspects of leakage of stored liquids or solids.
(4) Cylindrical and conical panels are not explicitly covered by this document. However, the provisions of 9.8 can be used provided that appropriate boundary conditions are taken into account.  
(5) This document defines the characteristic and design values of the resistance of the structure.
(6) This document is concerned with the requirements for design against the ultimate limit states of:
—   plastic failure;
—   cyclic plasticity;
—   buckling;
—   fatigue.
(7) Overall equilibrium of the structure (sliding, uplifting, overturning) is not included in this document. Special considerations for specific applications are included in the relevant application parts of EN 1993.
(8) Detailed formulae for the simple calculation of unstiffened cylinders, cones and spherical domes are given in the Annexes.
(9) Provisions for simple calculations on specific stiffened shell types are given in EN 1993-4-1.
(10) This document is intended for application to steel shell structures. Where no standard exists for shell structures made of other metals, including high strength steels, the provisions of this document are applicable provided the appropriate material properties of the metal are taken into account.
(11) The provisions of this document are intended to be applied within the temperature ranges defined in the relevant EN 1993 application parts.
(12) Where no application part defines a different range, this document applies to structures within the following limits:
—   design metal temperatures lie within the range −50 °C to +100 °C, except when using the special provisions given in 5.1;
—   radius to thickness ratios (r/t) within the range 50 to 2 000;
—   manufactured circular hollow sections according to EN 10210 and EN 10219 are outside the scope of this document and are covered by EN 1993-1-1. However, if no other provisions are available, the rules of this document are useful for manufactured circular hollow sections. In particular, this document is applicable to the design of manufactured piles (see EN 1993-5) provided the imperfections and tolerance requirements of EN 1993-5 are adopted in place of those specified in this document, and where no other standard covers the specific pile geometry.
NOTE 1   Experimental and theoretical data relating to manufactured circular hollow sections were not considered when this document was drafted. The application of this document to such structures therefore remains the responsibility of the user.  
NOTE 2   The stress design rules of this document can be rather conservative if applied to some geometries and loading conditions for relatively thick-walled shells.
NOTE 3   Thinner shells than r/t = 2 000 can be treated using these provisions but the provisions have not been verified for such thin shells.
NOTE 4   The maximum temperature is restricted so that the influence of creep can be ignored where high temperature creep effects are not covered by the relevant application part.
[...]

Eurocode 3 - Bemessung und Konstruktion von Stahlbauten - Teil 1-6: Festigkeit und Stabilität von Schalen

1.1   Anwendungsbereich von FprEN 1993-1-6
(1) FprEN 1993-1-6 enthält Grundregeln für die Tragwerksplanung von Stahlkonstruktionen in Form von Rotationsschalen (rotationssymmetrische Schalen).
(2) Dieses Dokument ist unter Anwendung sowohl algebraischer als auch rechnergestützter Verfahren auf unversteifte zusammengesetzte rotationssymmetrische Schalen, die durch Umformen isotroper Walzbleche hergestellt werden, sowie unter Anwendung rechnergestützter Verfahren auf versteifte rotationssymmetrische Schalen mit unterschiedlichen Wandkonstruktionen anwendbar. Es gilt auch für zugehörige Kreis- oder Kreisringplatten sowie für stabförmige Ring- und Längssteifen, soweit sie Teile der vollständigen Schalenkonstruktion sind. Die allgemeinen rechnergestützten Verfahren gelten für alle Schalenformen.
(3) Dieses Dokument gilt nicht für industriell hergestellte Schalen oder für Schalenplatten oder elliptische Schalenformen mit der Ausnahme, dass die allgemeinen rechnergestützten Verfahren für alle Schalenkonstruktionen gelten. Es gilt nicht für Tragwerke unter dynamischer oder Erdbebenbeanspruchung. Es deckt keine Dichtigkeitsaspekte in Zusammenhang mit gelagerten Flüssigkeiten oder Feststoffen ab.
(4) Zylindrische und kegelförmige Schalenteile,  felder und  abschnitte werden in diesem Dokument nicht explizit behandelt. Die Bestimmungen nach 9.8 können jedoch angewendet werden, sofern die zutreffenden Randbedingungen berücksichtigt werden.
(5) Dieses Dokument definiert die charakteristischen Werte und die Bemessungswerte des Tragwerkswiderstands.
(6) Dieses Dokument behandelt die Anforderungen an die Bemessung gegen die folgenden Grenzzustände der Tragfähigkeit:
-   plastisches Versagen;
-   zyklisches Plastizieren;
-   Beulen;
-   Ermüdung.
(7) Das Gesamtgleichgewicht des Tragwerks (Gleiten, Abheben, Umkippen) ist nicht Gegenstand dieses Dokuments. Besondere Überlegungen für spezielle Anwendungen werden in den einschlägigen Anwendungsteilen von EN 1993 behandelt.
(8) In den Anhängen sind detaillierte Gleichungen für die einfache Berechnung von unversteiften Zylindern, Kegeln und halbkugelförmigen Kuppeln angegeben.
(9) Bestimmungen für einfache Berechnungen bestimmter versteifter Schalentypen sind in EN 1993-4-1 angegeben.
(10) Dieses Dokument ist zur Anwendung auf stählerne Schalenkonstruktionen vorgesehen. In Abwesenheit bestehender Normen zu Schalenkonstruktionen aus anderen Metallen, einschließlich hochfesten Stählen, gelten die Bestimmungen dieses Dokuments unter der Voraussetzung, dass die jeweiligen Baustoffeigenschaften des Metalls berücksichtigt werden.
(11) Die Bestimmungen dieses Dokuments sind zur Anwendung innerhalb der in den einschlägigen Anwendungsteilen von EN 1993 definierten Temperaturbereiche vorgesehen.
(12) Sofern kein abweichender Bereich in einem Anwendungsteil festgelegt ist, gilt dieses Dokument für Tragwerke innerhalb der folgenden Grenzen:
-   Bemessungswerte der Metalltemperatur liegen innerhalb des Bereichs von −50 °C bis +100 °C, ausgenommen bei Anwendung der speziellen Bestimmungen nach 5.1;
-   Radius/Dicken-Verhältnisse (r/t) liegen innerhalb des Bereichs von 50 bis 2 000;
-   industriell hergestellte kreisförmige Hohlprofile nach EN 10210 und EN 10219 fallen nicht in den Anwendungsbereich dieser Norm und werden durch EN 1993-1-1 abgedeckt. Liegen jedoch keine anderen Bestimmungen vor, sind die Regeln dieses Dokuments nützlich für industriell hergestellte kreisförmige Hohlprofile. Dieses Dokument ist insbesondere anwendbar für die Bemessung industriell hergestellter Pfähle (siehe EN 1993-5), sofern die Anforderungen bezüglich Imperfektionen und Toleranzen nach EN 1993-5 statt der in diesem Dokument festgelegten angewendet werden und die jeweilige Pfahlgeometrie durch keine andere Norm abgedeckt wird.
...

Eurocode 3 - Calcul des structures en acier - Partie 1-6: Résistance et stabilité des structures en coque

1.1   Domaine d'application du l’EN 1993-1-6
(1) L’EN 1993-1-6 établit les règles de dimensionnement des structures en plaques d'acier ayant la forme d'une coque de révolution (coque axisymétrique).
(2) Le présent document s'applique aux coques axisymétriques fabriquées non raidies, formées à partir de plaques laminées isotropes à l'aide de procédures algébriques et informatiques, ainsi qu'aux coques axisymétriques raidies présentant différentes constructions de parois, à l'aide de procédures informatiques. Il s'applique également aux plaques annulaires ou circulaires et aux poutres annulaires et raidisseurs verticaux associés lorsqu'ils font partie de la structure complète en coque. Les procédures informatiques générales s'appliquent à toutes les formes de coques.
(3) Le présent document ne s'applique ni aux coques manufacturées, ni aux panneaux de coques, ni aux coques de forme elliptique, à l'exception du fait que ses procédures informatiques sont applicables à toutes les structures en coque. Le présent document ne s'applique pas aux structures soumises à des charges sismiques ou autres charges dynamiques. Il ne traite pas des aspects liés aux fuites de liquides ou solides stockés.
(4) Les panneaux cylindriques et coniques ne sont pas explicitement couverts par le présent document. Cependant, les dispositions du paragraphe 9.8 peuvent être utilisées sous réserve de prendre en compte les conditions aux limites appropriées.
(5) Le présent document définit les valeurs caractéristiques et de calcul de la résistance de la structure.
(6) Le présent document énonce les exigences pour le calcul aux états limites ultimes de :
-   rupture plastique ;
-   plasticité cyclique ;
-   voilement ;
-   fatigue.
(7) L'équilibre global de la structure (glissement, soulèvement, renversement) ne figure pas dans le présent document. Des considérations particulières concernant des applications spécifiques figurent dans les parties applicatives appropriées de l'EN 1993.
(8) Les formules détaillées pour le calcul simple des cylindres, cônes et dômes sphériques non raidis sont données en Annexes.
(9) Les dispositions relatives aux calculs simples sur des types de coques raidies spécifiques sont données dans l'EN 1993-4-1.
(10) Le présent document est destiné à être appliqué aux structures en coque en acier. En l'absence de norme applicable aux structures en coque constituées d'autres métaux, y compris d'aciers à haute résistance, les dispositions du présent document s'appliquent à condition de prendre en compte les propriétés de matériau appropriées du métal concerné.
(11) Les dispositions du présent document sont destinées à être appliquées dans les plages de températures définies dans les parties applicatives appropriées de l'EN 1993.
(12) Lorsqu'aucune partie applicative ne définit de plage différente, le présent document s'applique aux structures dans les limites suivantes :
-   les valeurs de calcul des températures du métal se situent dans la plage de −50 °C à +100 °C, sauf lorsque les dispositions particulières énoncées en 5.1 sont appliquées ;
-   les rapports rayon-épaisseur (r/t) se situent dans la plage de 50 à 2 000 ;
-   les profils creux circulaires manufacturés conformément à l'EN 10210 et à l'EN 10219 n'entrent pas dans le domaine d'application de la présente norme et sont couverts par l'EN 1993-1-1. Cependant, en l'absence de toute autre disposition, les règles du présent document sont utiles pour les profils creux circulaires manufacturés. Le présent document s'applique en particulier au calcul de pieux manufacturés (voir EN 1993-5), à condition d'adopter les imperfections et les exigences de tolérances de l'EN 1993-5 en lieu et place de celles spécifiées dans le présent document, et lorsqu'aucune autre norme ne traite de la géométrie spécifique du pieu.
...

Evrokod 3 - Projektiranje jeklenih konstrukcij - 1-6. del: Trdnost in stabilnost lupinastih konstrukcij

General Information

• Status: Not Published
• Public Enquiry End Date: 07-Jun-2023
• ICS: 91.010.30 - Technical aspects
• ICS: 91.080.13 - Steel structures
• Technical Committee: KON - Structures
• Current Stage: 5020 - Formal vote (FV) (Adopted Project)
• Start Date: 11-Nov-2024
• Due Date: 30-Dec-2024
• Completion Date: 01-Aug-2025
• Directive: 305/2011 - Regulation (eu) No 305/2011 of the European Parliament and of the Council of 9 march 2011 laying down harmonised conditions for the marketing of construction products and repealing council directive 89/106/eec
• Mandate: M/515 - Mandate for amending existing Eurocodes and extending the scope of structural Eurocodes
• Ref Project: EN 1993-1-6:2025 - Eurocode 3 - Design of steel structures - Part 1-6: Strength and stability of shell structures

Relations

• Replaces: SIST EN 1993-1-6:2007/A1:2017 - Eurocode 3 - Design of steel structures - Part 1-6: Strength and Stability of Shell Structures
• Effective Date: 04-Jun-2025
• Replaces: SIST EN 1993-1-6:2007/AC:2009 - Eurocode 3 - Design of steel structures - Part 1-3: General rules - Supplementary rules for cold-formed members and sheeting
• Effective Date: 04-Jun-2025
• Revises: SIST EN 1993-1-6:2007 - Eurocode 3 - Design of steel structures - Part 1-6: Strength and Stability of Shell Structures
• Effective Date: 18-Jan-2023

Overview

EN 1993-1-6:2025 - Eurocode 3: Strength and stability of shell structures provides harmonized European rules for the structural design of plated steel axisymmetric (shell-of-revolution) structures. It covers unstiffened fabricated axisymmetric shells made from isotropic rolled plates using algebraic and computational methods, and stiffened axisymmetric shells when analysed with computational procedures. The standard defines characteristic and design resistances and addresses design against ultimate limit states including plastic failure, cyclic plasticity, buckling and fatigue. It excludes manufactured shells, elliptical forms (except for general computational methods), seismic/dynamic loading and leakage aspects of stored media.

Key Topics

• Scope & applicability: Unstiffened and stiffened axisymmetric shells, associated circular/annular plates, beam-section rings and stringer stiffeners when part of the shell.
• Design limits: Typical temperature range −50 °C to +100 °C (unless application parts specify otherwise); radius-to-thickness ratio (r/t) normally between 50 and 2 000.
• Limit states covered: Plastic failure, cyclic plasticity, buckling and fatigue (ultimate limit states).
• Analysis methods: Algebraic (formulae) and computational procedures; computational analyses include LBA, MNA and GMNIA/GMNA approaches as referenced in the Eurocode text.
• Material & geometry: Rules for isotropic rolled steels; applicability to other metals only if appropriate material properties are adopted.
• Annexes: Informative and normative annexes provide membrane theory, plastic reference resistances and extensive formulae for cylinders, cones and spherical domes and buckling resistance (useful for hand calculations and validation of numerical models).
• Limitations & exclusions: Manufactured circular hollow sections (EN 10210/10219) are covered elsewhere (EN 1993-1-1); structures under seismic/dynamic loads and overall equilibrium (sliding, uplift, overturning) are outside the standard.

Applications

This Eurocode part is intended for:

• Structural engineers and designers of steel shell structures (cylindrical tanks, domes, cones and similar axisymmetric components) who need validated rules for strength and stability.
• Fabricators and detailers using unstiffened/stiffened rolled plate construction.
• Software developers, researchers and verification teams performing computational buckling and plasticity analyses.
• Authorities and standards committees referencing harmonized European design methods for shell resistance.

Note: EN 1993-1-6 provides structural strength and stability rules only - project-specific aspects such as leakage control, dynamic/seismic provisions or national safety values should be taken from relevant application parts or National Annexes.

Related Standards

• EN 1993-1-1 (general rules for buildings; also covers manufactured hollow sections)
• EN 1993-4-1 (provisions for specific stiffened shell types)
• EN 1993-5 (piling; guidance when applying shell rules to piles)
• EN 1990 / EN 1991 (Basis of design and actions on structures)

Standards Content (Sample)

SLOVENSKI STANDARD
oSIST prEN 1993-1-6:2023
01-maj-2023
Evrokod 3 - Projektiranje jeklenih konstrukcij - 1-6. del: Trdnost in stabilnost
lupinastih konstrukcij
Eurocode 3 - Design of steel structures - Part 1-6: Strength and Stability of Shell
Structures
Eurocode 3 - Bemessung und Konstruktion von Stahlbauten - Teil 1-6: Festigkeit und
Stabilität von Schalen
Eurocode 3 - Calcul des structures en acier - Partie 1-6: Résistance et stabilité des
structures en coque
Ta slovenski standard je istoveten z: prEN 1993-1-6
ICS:
91.010.30 Tehnični vidiki Technical aspects
91.080.13 Jeklene konstrukcije Steel structures
oSIST prEN 1993-1-6:2023 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

oSIST prEN 1993-1-6:2023
oSIST prEN 1993-1-6:2023
DRAFT
EUROPEAN STANDARD
prEN 1993-1-6
NORME EUROPÉENNE
EUROPÄISCHE NORM
March 2023
ICS 91.010.30; 91.080.13 Will supersede EN 1993-1-6:2007
English Version
Eurocode 3 - Design of steel structures - Part 1-6: Strength
and Stability of Shell Structures
Eurocode 3 - Calcul des structures en acier - Partie 1-6: Eurocode 3 - Bemessung und Konstruktion von
Résistance et stabilité des structures en coque Stahlbauten - Teil 1-6: Festigkeit und Stabilität von
Schalen
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee
CEN/TC 250.
If this draft becomes a European Standard, CEN members are bound to comply with the CEN/CENELEC Internal Regulations
which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.

This draft European Standard was established by CEN 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 CEN-CENELEC
Management Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are
aware and to provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without
notice and shall not be referred to as a European Standard.

EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2023 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 1993-1-6:2023 E
worldwide for CEN national Members.

oSIST prEN 1993-1-6:2023
prEN 1993-1-6:2023 (E)
Contents Page
European foreword . 5
0 Introduction . 6
1 Scope . 9
1.1 Scope of prEN 1993-1-6 . 9
1.2 Assumptions . 10
2 Normative references . 11
3 Terms, definitions and symbols . 11
3.1 Definitions . 11
3.2 Symbols . 21
3.3 Sign conventions . 28
4 Basis of design . 28
4.1 General rules . 28
4.2 Types of analysis . 29
4.3 Shell boundary conditions . 32
4.4 Verification by the partial factor method . 33
5 Materials and geometry . 34
5.1 Material properties . 34
5.2 Design values of geometrical data . 35
5.3 Geometrical tolerances and geometrical imperfections . 35
6 Structural analysis . 36
6.1 Types of design . 36
6.2 Stress resultants and stresses in shells . 38
6.3 Ultimate limit states to be considered . 42
6.4 Concepts for the limit state verifications . 45
7 Plastic failure Limit State (LS1) . 46
7.1 Design values of actions . 46
7.2 Stress design . 46
7.3 Design by computational MNA or GMNA analysis . 48
7.4 Design using standard formulae . 49
8 Cyclic plasticity Limit State (LS2) . 49
8.1 Design values of actions . 49
8.2 Stress design . 49
8.3 Design by computational GMNA analysis. 50
8.4 Design using standard formulae . 51
9 Buckling Limit State (LS3) . 51
9.1 Design values of actions . 51
9.2 Special definitions and symbols . 51
9.3 Buckling-relevant boundary conditions . 52
9.4 Buckling-relevant geometrical tolerances . 55
9.5 Stress design . 65
9.6 Design using reference resistances . 69
9.7 Design by computational analysis using LBA and MNA analyses . 71
9.8 Design by computational analysis using GMNIA analysis . 76
oSIST prEN 1993-1-6:2023
prEN 1993-1-6:2023 (E)
10 Fatigue Limit State (LS4). 83
10.1 Design values of actions . 83
10.2 Stress design . 83
Annex A (informative) Membrane theory stresses in unstiffened shells . 87
A.1 Use of this Annex . 87
A.2 Scope and field of application . 87
A.3 General . 87
A.4 Cylindrical shells . 89
A.5 Conical shells. 90
A.6 Spherical shells . 92
Annex B (informative) Formulae for plastic reference resistances of unstiffened shells
and circular plates . 93
B.1 Use of this Annex . 93
B.2 Scope and field of application . 93
B.3 General . 93
B.4 Uniform unstiffened cylindrical shells . 94
B.5 Cylindrical shells with local ring stiffeners . 97
B.6 Junctions between conical and cylindrical shells . 99
B.7 Circular plates with axisymmetric boundary conditions . 101
Annex C (informative) Formulae for linear elastic membrane and bending stresses in
unstiffened cylindrical shells and circular plates . 103
C.1 Use of this Annex . 103
C.2 Scope and field of application . 103
C.3 General . 103
C.4 Clamped base cylindrical shells . 104
C.5 Pinned base cylindrical shells . 108
C.6 Internal conditions in cylindrical shells . 111
C.7 Local ring stiffener on a cylindrical shell . 114
C.8 Circular plates with simply supported boundary conditions . 116
C.9 Circular plates with clamped boundary conditions . 117
Annex D (normative) Formulae to determine the buckling resistance of unstiffened
shells when using stress design . 119
D.1 Use of this annex . 119
D.2 Scope and field of application . 119
D.3 Cylindrical shells of constant wall thickness: basic load cases . 119
D.4 Cylindrical shells of constant wall thickness: combined cases . 129
D.5 Cylindrical shells of stepwise variable wall thickness . 134
D.6 Lap jointed cylindrical shells . 143
D.7 Complete and truncated conical shells. 145
oSIST prEN 1993-1-6:2023
prEN 1993-1-6:2023 (E)
Annex E (normative) Formulae to determine the buckling resistance of unstiffened
shells when using reference resistance design . 150
E.1 Use of this annex . 150
E.2 Scope and field of application . 150
E.3 Cylindrical shells under global bending . 150
E.4 Spherical dome shells . 155
Bibliography . 160

oSIST prEN 1993-1-6:2023
prEN 1993-1-6:2023 (E)
European foreword
This document (prEN 1993-1-6:2023) has been prepared by Technical Committee CEN/TC 250
“Structural Eurocodes”, the secretariat of which is held by BSI. CEN/TC 250 is responsible for all
Structural Eurocodes and has been assigned responsibility for structural and geotechnical matters
by CEN.
This document is currently submitted to the CEN Enquiry.
This document will supersede EN 1993-1-6:2007 and its amendments and corrigenda.
The first generation of EN Eurocodes was published between 2002 and 2007. This document forms
part of the second generation of the Eurocodes, which have been prepared under Mandate M/515
issued to CEN by the European Commission and the European Free Trade Association.
The Eurocodes have been drafted to be used in conjunction with relevant execution, material,
product and test standards, and to identify requirements for execution, materials, products and
testing that are relied upon by the Eurocodes.
The Eurocodes recognize the responsibility of each Member State and have safeguarded their right
to determine values related to regulatory safety matters at national level through the use of
National Annexes.
oSIST prEN 1993-1-6:2023
prEN 1993-1-6:2023 (E)
0 Introduction
0.1 Introduction to the Eurocodes
The Structural Eurocodes comprise the following standards generally consisting of a number of
Parts:
— EN 1990, Eurocode: Basis of structural and geotechnical design
— EN 1991, Eurocode 1: Actions on structures
— EN 1992, Eurocode 2: Design of concrete structures
— EN 1993, Eurocode 3: Design of steel structures
— EN 1994, Eurocode 4: Design of composite steel and concrete structures
— EN 1995, Eurocode 5: Design of timber structures
— EN 1996, Eurocode 6: Design of masonry structures
— EN 1997, Eurocode 7: Geotechnical design
— EN 1998, Eurocode 8: Design of structures for earthquake resistance
— EN 1999, Eurocode 9: Design of aluminium structures
— New parts are under development, e.g. Eurocode for design of structural glass
The Eurocodes are intended for use by designers, clients, manufacturers, constructors, relevant
authorities (in exercising their duties in accordance with national or international regulations),
educators, software developers, and committees drafting standards for related product, testing and
execution standards.
NOTE Some aspects of design are most appropriately specified by relevant authorities or, where not
specified, can be agreed on a project-specific basis between relevant parties such as designers and clients. The
Eurocodes identify such aspects making explicit reference to relevant authorities and relevant parties.
0.2 Introduction to EN 1993 (all parts)
EN 1993 (all parts) applies to the design of buildings and civil engineering works in steel. It
complies with the principles and requirements for the safety and serviceability of structures, the
basis of their design and verification that are given in EN 1990 – Basis of structural design.
EN 1993 (all parts) is concerned only with requirements for resistance, serviceability, durability
and fire resistance of steel structures. Other requirements, e.g. concerning thermal or sound
insulation, are not covered.
EN 1993 is subdivided in various parts:
EN 1993-1, Design of Steel Structures — Part 1: General rules and rules for buildings;
EN 1993-2, Design of Steel Structures — Part 2: Steel bridges;
EN 1993-3, Design of Steel Structures — Part 3: Towers, masts and chimneys;
EN 1993-4, Design of Steel Structures — Part 4: Silos and tanks;
EN 1993-5, Design of Steel Structures — Part 5: Piling;
oSIST prEN 1993-1-6:2023
prEN 1993-1-6:2023 (E)
EN 1993-6, Design of Steel Structures — Part 6: Crane supporting structures;
EN 1993-7 , Design of steel structures — Part 7: Design of sandwich panels.
EN 1993-1 in itself does not exist as a physical document, but comprises the following 14 separate
parts, the basic part being EN 1993-1-1:
EN 1993-1-1, Design of Steel Structures — Part 1-1: General rules and rules for buildings;
EN 1993-1-2, Design of Steel Structures — Part 1-2: Structural fire design;
EN 1993-1-3, Design of Steel Structures — Part 1-3: Cold-formed members and sheeting;
NOTE Cold formed hollow sections supplied according to EN 10219 are covered in EN 1993-1-1.
EN 1993-1-4, Design of Steel Structures — Part 1-4: Stainless steels;
EN 1993-1-5, Design of Steel Structures — Part 1-5: Plated structural elements;
EN 1993-1-6, Design of Steel Structures — Part 1-6: Strength and stability of shell structures;
EN 1993-1-7, Design of Steel Structures — Part 1-7: Plate assemblies with elements under transverse
loads;
EN 1993-1-8, Design of Steel Structures — Part 1-8: Design of joints;
EN 1993-1-9, Design of Steel Structures — Part 1-9: Fatigue strength of steel structures;
EN 1993-1-10, Design of Steel Structures — Part 1-10: Selection of steel for fracture toughness and
through-thickness properties;
EN 1993-1-11, Design of Steel Structures — Part 1-11: Design of structures with tension components
made of steel;
EN 1993-1-12, Design of Steel Structures — Part 1-12: Additional rules for steel grades up to S960;
EN 1993-1-13 , Design of Steel Structures — Part 1-13: Beams with large web openings;
EN 1993-1-14 , Design of Steel Structures — Part 1-14: Design assisted by finite element analysis.
All subsequent parts EN 1993-1-2 to EN 1993-1-14 treat general topics that are independent from
the structural type such as structural fire design, cold-formed members and sheeting, stainless
steels, plated structural elements, etc.
All subsequent parts numbered EN 1993-2 to EN 1993-7 treat topics relevant for a specific
structural type such as steel bridges, towers, masts and chimneys, silos and tanks, piling, crane
supporting structures, etc. EN 1993-2 to EN 1993-7 refer to the generic rules in EN 1993-1 and
supplement, modify or supersede them.
0.3 Introduction to prEN 1993-1-6
prEN 1993-1-6 gives design requirements for steel shell structures that are subject to forces and
pressures that induce membrane and bending stress resultants in the shell. It also covers annular
plates and ring stiffeners. Its provisions can be used for a wide variety of stiffened and unstiffened
curved structures through the application of computational methods. It is applicable to silos, tanks,
chimneys, wind turbine towers, biodigesters and piles.

Under preparation.
Under preparation.
Under preparation.
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0.4 Verbal forms used in the Eurocodes
The verb “shall" expresses a requirement strictly to be followed and from which no deviation is
permitted in order to comply with the Eurocodes.
The verb “should” expresses a highly recommended choice or course of action. Subject to national
regulation and/or any relevant contractual provisions, alternative approaches could be
used/adopted where technically justified.
The verb “may" expresses a course of action permissible within the limits of the Eurocodes.
The verb “can" expresses possibility and capability; it is used for statements of fact and clarification
of concepts.
0.5 National Annex for prEN 1993-1-6
National choice is allowed in this standard where explicitly stated within notes. National choice
includes the selection of values for Nationally Determined Parameters (NDPs).
The national standard implementing prEN 1993-1-6 can have a National Annex containing all
national choices to be used for the design of buildings and civil engineering works to be constructed
in the relevant country.
When no national choice is given, the default choice given in this standard is to be used.
When no national choice is made and no default is given in this standard, the choice can be specified
by a relevant authority or, where not specified, agreed for a specific project by appropriate parties.
National choice is allowed in prEN 1993-1-6 through notes to the following:
4.4 (3) 6.3.2 (3) 6.3.4 (2) 9.8.2 (12)
National choice is allowed in prEN 1993-1-6 on the application of the following informative
annexes:
Annex A Annex B Annex C
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1 Scope
1.1 Scope of prEN 1993-1-6
(1) prEN 1993-1-6 provides rules for the structural design of plated steel structures that have the
form of a shell of revolution (axisymmetric shell).
(2) This document is applicable to unstiffened fabricated axisymmetric shells formed from isotropic
rolled plates using both algebraic and computational procedures, and to stiffened axisymmetric
shells with different wall constructions using computational procedures. It also applies to
associated circular or annular plates and to beam section rings and stringer stiffeners where they
form part of the complete shell structure. The general computational procedures are applicable to
all shell forms.
(3) This document does not apply to manufactured shells or to shell panels or to elliptical shell
forms, except that its computational procedures are applicable to all shell structures. This
document does not apply to structures under seismic or other dynamic loading. It does not cover
the aspects of leakage of stored liquids or solids.
(4) Cylindrical and conical panels are not explicitly covered by this document. However, the
provisions of subclause 9.8 can be used provided that appropriate boundary conditions are taken
into account.
(5) This document defines the characteristic and design values of the resistance of the structure.
(6) This document is concerned with the requirements for design against the ultimate limit states
of:
— plastic failure;
— cyclic plasticity;
— buckling;
— fatigue.
(7) Overall equilibrium of the structure (sliding, uplifting, overturning) is not included in this
document. Special considerations for specific applications are included in the relevant application
parts of EN 1993.
(8) Detailed formulae for the simple calculation of unstiffened cylinders, cones and spherical domes
are given in the Annexes.
(9) Provisions for simple calculations on specific stiffened shell types are given in EN 1993-4-1.
(10) This document is intended for application to steel shell structures. Where no standard exists
for shell structures made of other metals, including high strength steels, the provisions of this
document are applicable provided the appropriate material properties of the metal are taken into
account.
(11) The provisions of this document are intended to be applied within the temperature ranges
defined in the relevant EN 1993 application parts.
(12) Where no application part defines a different range, this document applies to structures within
the following limits:
— design metal temperatures lie within the range −50 °C to +100 °C, except when using the
special provisions given in 5.1;
— radius to thickness ratios (r/t) within the range 50 to 2 000;
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— manufactured circular hollow sections according to EN 10210 and EN 10219 are outside the
scope of this standard and are covered by EN 1993-1-1. However, if no other provisions are
available, the rules of this document are useful for manufactured circular hollow sections. In
particular, this document is applicable to the design of manufactured piles (see EN 1993-5)
provided the imperfections and tolerance requirements of EN 1993-5 are adopted in place of
those specified in prEN 1993-1-6, and where no other standard covers the specific pile
geometry.
NOTE 1 Experimental and theoretical data relating to manufactured circular hollow sections were not
considered when this document was drafted. The application of this document to such structures therefore
remains the responsibility of the user.
NOTE 2 The stress design rules of this document can be rather conservative if applied to some geometries
and loading conditions for relatively thick-walled shells.
NOTE 3 Thinner shells than r/t = 2 000 can be treated using these provisions but the provisions have not
been verified for such thin shells.
NOTE 4 The maximum temperature is restricted so that the influence of creep can be ignored where high
temperature creep effects are not covered by the relevant application part.
NOTE 5 Where temperatures outside the above range are involved, the thermally adjusted properties can
be found in EN 1993-1-2 or other CEN standards as appropriate. Where no other standard is available, refer to
EN 1993-1-2 which, though intended for the design of steel structures against fire, gives general temperature-
dependent material properties that can be more widely used (see 5.1(10)).
1.2 Assumptions
(1) Unless specifically stated, the provisions of EN 1990, EN 1991 (all parts) and the other relevant
parts of EN 1993-1 (all parts) apply.
(2) The design methods given in prEN 1993-1-6 are applicable if:
— the execution quality is as specified in EN 1090-2, and
— the construction materials and products used are as specified in the relevant parts of EN 1993
(all parts), or in the relevant material and product specifications.
NOTE The buckling-related tolerance requirements of this document differ in some aspects from those of
EN 1090-2 (see Clause 9).
(3) The provisions in this document apply to materials that satisfy the brittle fracture provisions
given in EN 1993-1-4, EN 1993-1-10 and EN 1993-1-12.
(4) In this document, it is assumed that wind loading, seismic actions and bulk solids flow can, in
general, be treated as quasi-static actions.
(5) Dynamic effects are outside the scope of prEN 1993-1-6, and are covered by the relevant
application part of EN 1993 or EN 1998, including the consequences for fatigue. However, the stress
resultants arising from dynamic behaviour are treated in this part as quasi-static.
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2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments)
applies.
NOTE See the Bibliography for a list of other documents cited that are not normative references, including
those referenced as recommendations (i.e. in ‘should’ clauses), permissions (‘may’ clauses), possibilities ('can'
clauses), and in notes.
EN 1090-2, Execution of steel structures and aluminium structures — Part 2: Technical requirements
for steel structures
EN 1990, Eurocode: Basis of structural and geotechnical design
EN 1991 (all parts), Eurocode 1: Actions on structures
EN 1993 (all parts), Eurocode 3: Design of steel structures
ISO 8930, General principles on reliability for structures — Vocabulary
3 Terms, definitions and symbols
For the purposes of this document, the terms and definitions given in EN 1990, EN 1993-1-1,
ISO 8930 and the following apply.
3.1 Definitions
3.1.1 Structural forms and geometry
3.1.1.1
base ring
structural member that passes around the circumference of the shell of revolution at the base and
provides a means of attachment of the shell to a foundation or other structural member, needed to
ensure that the assumed boundary conditions are achieved in practice
3.1.1.2
circumferential joint
joint that passes around the circumference of an axisymmetric shell
3.1.1.3
complete shell or shell assembly
shell composed of a number of shell segments (cylindrical, conical, spherical, etc.)
Note 1 to entry: In this standard, each segment of the shell assembly is assumed to be a shell of revolution.
3.1.1.4
constructional detail
part of a shell with a geometry that causes locally raised stresses relevant to the fatigue limit state
(LS4), such as welded joints, bolted joints and connections.
Note 1 to entry: The geometric feature that causes the stress raising effect is also referred to as a “notch” in
EN 1993-1-9.
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3.1.1.5
course
set of rolled plates connected by vertical joints that make up a single layer of shell between
horizontal joints
Note 1 to entry: Several courses of the same thickness can together become a strake.
3.1.1.6
fabricated shell
shell structure that is constructed by rolling plates into curved cylindrical panel sections and then
assembling them by welding or bolting into a complete shell form
3.1.1.7
joint
line between two pieces of shell that are part of the same shell segment but fabricated from
different pieces of shell plate
Note 1 to entry: A joint can be welded or bolted or connected in any other manner. The term “joint” is
extensively used in shell structures, but it is used with a slightly different meaning from that found in EN 1993-
1-8.
3.1.1.8
junction
line at which two or more shell segments meet
Note 1 to entry: A junction can include a stiffener, which can be treated as a junction at the circumferential line
of attachment of a ring stiffener to the shell.
3.1.1.9
lap joint
joint in which the two shell plates overlap across the joint, increasing the total shell thickness
locally
3.1.1.10
manufactured shell
shell or tubular member that is made in a factory by controlled processes in which the complete
circular or elliptical form is achieved through folding, rolling or similar processes and using
longitudinal or spiral welding
Note 1 to entry: Manufactured shells or tubular members are typically manufactured to meet the
specifications of EN 10210 or EN 10219. Manufactured shells are outside the scope of this document except
where permitted by 1.1 (3) and 1.1 (12).
3.1.1.11
meridian and meridional direction
line on a shell surface that lies in the plane through the axisymmetric shell axis
Note 1 to entry: The meridional direction is the tangent to the meridian at any point. In a cylinder, the
meridian is parallel to the axis and the meridional direction is synonymous with the axial direction. In conical
shells the meridian is straight but inclined to the axis. In other shell forms the meridional direction changes
with axial position.
3.1.1.12
meridional joint
joint that lies on the meridian of an axisymmetric shell
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3.1.1.13
middle surface
surface that lies midway between the inside and outside surfaces of the shell at every point, which
is the reference surface for analysis, and can be discontinuous at changes of thickness or at shell
junctions, leading to eccentricities that can be important to the shell structural behaviour
Note 1 to entry: In a shell stiffened on either one or both surfaces, the reference middle surface is still taken as
the middle surface of the curved shell plate.
3.1.1.14
notch
position in a constructional detail where locally raised stresses arise that are relevant to the fatigue
limit state (LS4)
Note 1 to entry: The term “notch” is widely used in EN 1993-1-9.
3.1.1.15
rib
local member that provides a primary load carrying path for bending down the meridian of the
shell, representing a generator of the shell of revolution, used to transfer or distribute transverse
loads by bending
3.1.1.16
ring beam or ring girder
circumferential stiffener that has bending stiffness and strength both in the plane of the shell
circular section and normal to that plane, acting as a primary load carrying structural member and
provided for the distribution of local loads into the shell
3.1.1.17
ring stiffener
local stiffening member that passes around the circumference of the shell of revolution at a given
point on the meridian, normally assumed to have no stiffness for deformations out of its own plane
(meridional displacements of the shell) but to be stiff for deformations in the plane of the ring, and
provided to increase the stability or to introduce local loads acting in the plane of the ring
3.1.1.18
shell
structure or a structural component formed from a curved thin plate
Note 1 to entry: The curvature plays a vital role in its structural resistance and can be either in one direction
(cylinder or cone) or two directions (spherical, ellipsoidal, toroidal, hyperboloid etc.).
3.1.1.19
shell of revolution
shell whose geometric form is defined by a middle surface that is formed by rotating a meridional
generator line around a single axis through 2π radians
3.1.1.20
shell panel
incomplete shell of revolution
Note 1 to entry: The shell of revolution is termed incomplete if it has meridional boundaries that lie at
circumferential locations less than 2π radians apart.
Note 2 to entry: Shell panels are outside the scope of this document except where permitted by 1.1 (4).
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3.1.1.21
shell segment
shell of revolution in the form of a defined shell geometry, usually with a constant wall thickness
but sometimes consisting of multiple strakes
Note 1 to entry: A shell segment can be a cylinder, conical frustum, spherical frustum, annular plate, toroidal
knuckle or any other form of shell of revolution.
3.1.1.22
stepped wall
shell with a fixed geometric shape (cylinder, cone, etc.) in which different parts have different
thicknesses to accommodate the variation of local resistance requirements
3.1.1.23
strake
zone of constant thickness within a shell constructed with a stepped wall
3.1.1.24
stringer stiffener
local stiffening member that follows the meridian of the shell, representing a generator of the shell
of revolution, provided to increase the stability, or to assist with the introduction of local loads, but
not intended to provide a primary resistance to bending effects caused by transverse loads
3.1.2 Limit states
3.1.2.1
buckling (LS3)
ultimate limit state where the shell structure suddenly loses its stability under membrane
compression and/or shear, leading either to large displacements or to the shell being unable to
support the applied loads
3.1.2.2
cyclic plasticity (LS2)
ultimate limit state where repeated yielding is caused by cycles of loading and unloading, leading to
a low cycle fatigue failure where the local energy absorption capacity of the material is exhausted
3.1.2.3
fatigue (LS4)
ultimate limit state where more than N cycles of loading cause cracks to develop in any part of the
f
structure, so that further load cycles can lead to rupture
Note 1 to entry: This limit state is termed “high cycle fatigue” in EN 1990. The value of N is defined in 6.3.4(2).
f
EN 1993-1-9 has no provisions for numbers of cycles less than 10 000. For lower numbers of cycles involving
high stresses, Clause 8 (LS2) is relevant.
3.1.2.4
plastic failure limit state (LS1)
ultimate limit state where the shell develops zones of yielding with combined membrane and
bending deformations in a pattern such that its ability to resist increased loading of the same form
is deemed to be exhausted
Note 1 to entry: Many ductile shell structures can continue to resist increased loading with extensive yielding
and substantial changes of geometry. For these conditions, a limitation on deformation is used to define the
plastic failure limit state.
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3.1.2.5
tensile rupture (LS1)
ultimate limit state where the shell plate experiences gross section failure due to membrane tension
3.1.3 Actions
3.1.3.1
axial load
externally applied loading acting in the axial direction in an axisymmetric shell
3.1.3.2
axial compression
axial load inducing compressive membrane stresses in a cylindrical shell
3.1.3.3
external pressure
component of the surface loading acting normal to the shell in the inward direction q
Note 1 to entry: The magnitude of the external pressure can vary in both the meridional and circumferential
directions (e.g. under snow, see EN 1991-1-3, or wind, see EN 1991-1-4).
3.1.3.4
global bending
actions causing a cylindrical or conical shell to bend as a complete structure about an axis normal to
the axis of the shell
Note 1 to entry: This corresponds to a cosine variation (harmonic 1) of the axial stresses around the
circumference of the shell and is equivalent to beam bending.
3.1.3.5
hydrostatic pressure
pressure varying linearly with the axial coordinate in an axisymmetric shell, which is deemed to
have its axis vertical
3.1.3.6
internal pressure
component of the surface loading acting normal to the shell in the outward direction p
Note 1 to entry: The magnitude of the internal pressure can vary in both the meridional and circumferential
directions (e.g. under solids loading in a silo, see EN 1991-4, or under sloshing pressures in a tank, see
EN 1998-4, or tilt settlements under large diameter tanks).
3.1.3.7
local load
point applied force or distributed load acting on a limited part of the circumference of the shell and
over a limited height
3.1.3.8
partial vacuum
uniform net external pressure, typically caused by the removal of stored liquids, solids or gas from
within a container that is inadequately vented (see EN 1991-4)
3.1.3.9
patch load
local distributed load acting normal to the shell
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3.1.3.10
radial load
externally applied loading acting normal to the surface of a cylindrical shell or normal to the axis in
an axisymmetric shell
3.1.3.11
suction
uniform net external pressure q due to the reduced internal pressure in a shell (e.g. due to openings
or vents under wind action, see EN 1991-1-4 or due to partial vacuum)
Note 1 to entry: The external pressure is given a separate notation q to simplify the provisions of this
document. Otherwise many formulae would involve negative values of the outward pressure p.
3.1.3.12
thermal action
temperature variation either down the shell meridian, or around the shell circumference or through
the shell thickness, or combinations of these spatial variations
3.1.3.13
wall friction load
meridional component of the surface loading acting on the shell wall due to friction connected with
internal pressure (e.g. when solids are contained within the shell, see EN 1991-4)
3.1.4 Stress resultants and stresses in a shell
3.1.4.1
bending stress
bending stress resultant multiplied by 6 and divided by the square of the shell thickness (only
meaningful for conditions in which the shell is elastic)
Note 1 to entry: The subscript notation for a bending stress relates to the direction of the stress, not the axis
about which the shell is deformed.
3.1.4.2
bending stress resultants
bending and twisting moments per unit width of shell that arise as the integral of the first moment
of the distribution of direct and shear stresses acting parallel to the shell middle surface through
the thickness of the shell, such that under elastic conditions, each of these stress resultants induces
a stress state that varies linearly through the shell thickness, with value zero and the middle
surface, resulting in two bending moments and one twisting moment at any point (see Figure 3.3b)
Note 1 to entry: Under plastic and partially yielded conditions, the same stress resultants lead to different and
often complex stress patterns through the thickness.
3.1.4.3
membrane stress
membrane stress resultant divided by the shell thickness (see Figures 3.2 and 3.3a)
3.1.4.4
membrane stress resultant
force per unit width of the shell wall that arises as the integral of the distribution of direct and shear
stresses acting parallel to the shell middle surface through the thickness of the shell
Note 1 to entry: Under elastic conditions, each of these stress resultants induces a stress state that is uniform
through the shell thickness, resulting in three membrane stress resultants at any point (see Figures 3.2 and
3.3a).
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3.1.4.5
transverse shear stress resultants
forces per unit width of shell that arise as the integral of the distribution of shear stresses acting
normal to the shell middle surface through the thickness of the shell, such that under elastic
conditions, each of these stress resultants induces a stress state that varies parabolically through
the shell thi
...