SIST EN 1993-1-13:2024/oprA1:2026

Eurocode 3 - Design of steel structures - Part 1-13: Beams with large web openings

1.1   Scope of EN 1993-1-13
1.1.1   General
(1) This document gives supplementary provisions that extend the application of EN 1993-1-1 and EN 1993-1-5 to the design of rolled and welded steel sections with various shapes of web openings. The following cases are considered:
-   rolled or welded beams with single or widely spaced web openings;
-   rolled or welded beams with closely spaced web openings;
-   cellular beams with circular openings made by cutting and re-welding two parts of steel sections that may be different in dimensions;
-   beams with hexagonal and sinusoidal openings made by cutting and re-welding two parts of steel sections that may be different in dimensions.
(2) This document applies to uniform members with I or H profiles, which are symmetric about the weak axis. It does not apply to non-prismatic or curved beams although the same principles can apply.
(3) This document applies to steel beams with web openings that are subjected to sagging (positive) or to hogging (negative) bending moments.
(4) This document covers the verification of the resistance at the openings and their effects on the global behaviour of the beam, including lateral torsional buckling.
(5) Alternative methods are presented for beams with circular openings and with sinusoidal openings in which the forces and resistances are calculated by increments around or along the openings and which are suitable for computer methods.
(6) This document applies to web slenderness, hw/tw, not exceeding 121ε. The local checks at and between adjacent openings apply to web slenderness up to this limit. The material parameter ε is defined in EN 1993-1-1:2022, 5.2.5 (2).
NOTE   The limit of 121ε is the limit of a Class 4 web for a steel section with equal flanges. It is used as a convenient limit for the application of this document, including mono-symmetric sections.
(7) This document does not cover fatigue. In case of fatigue, EN 1993-1-9 applies.
(8) This document does not cover fire design. For the design in case of fire, EN 1993-1-2 applies.
(9) This document does not cover the buckling verification of members with web openings under axial force.
1.1.2   Shapes of web openings
(1) The different shapes of web openings that are considered in this document are shown in Figure 1.1.
Figure 1.1 - Different shapes of web openings in steel beams
1.1.3   Stiffened openings
(1) This document also covers openings in the web of beams that are reinforced by longitudinal stiffeners and/or transverse stiffeners on one or both sides of the web, see Figure 1.2.
NOTE   The National Annex can give rules for alternative types of stiffener.
Figure 1.2 - Stiffening of openings in beam webs
1.2   Assumptions
(1) Unless specifically stated, EN 1990, the EN 1991 series and EN 1993-1-1 apply.
(2) The design methods given in EN 1993-1-13 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 the EN 1993 series, or in the relevant material and product specifications.

Eurocode 3 - Bemessung und Konstruktion von Stahlbauten - Teil 1-13: Träger mit großen Stegöffnungen

Eurocode 3 - Calcul des structures en acier - Partie 1-13 : Poutres avec grandes ouvertures d'âme

Evrokod 3 - Projektiranje jeklenih konstrukcij - 1-13. del: Nosilci z velikimi mrežnimi odprtinami

1.1 Področje uporabe EN 1993-1-13
1.1.1 Splošno
(1) Ta dokument podaja dopolnilne določbe, ki razširjajo uporabo EN 1993-1-1 in EN 1993-1-5 na projektiranje valjanih in varjenih jeklenih profilov z različnimi oblikami odprtin v pasnicah. Obravnavani so naslednji primeri:
- valjani ali varjeni nosilci z enojnimi ali široko razmaknjenimi odprtinami v pasnicah;
- valjani ali varjeni nosilci z gosto razmaknjenimi odprtinami v pasnicah;
- celični nosilci s krožnimi odprtinami, izdelanimi z rezanjem in ponovnim varjenjem dveh delov jeklenih profilov, ki so lahko različnih dimenzij;
- nosilci s šesterokotnimi in sinusoidnimi odprtinami, izdelanimi z rezanjem in ponovnim varjenjem dveh delov jeklenih profilov, ki so lahko različnih dimenzij.
(2) Ta dokument se uporablja za enakomerne elemente s profili I ali H, ki so simetrični glede na šibko os. Ne velja za neprizmatične ali ukrivljene nosilce, čeprav se lahko uporabljajo ista načela.
(3) Ta dokument se uporablja za jeklene nosilce z odprtinami v pasnicah, ki so podvrženi upogibnim momentom v sagitalni (pozitivni) ali nagibni (negativni) smeri.
(4) Ta dokument zajema preverjanje odpornosti na odprtinah in njihov vpliv na globalno obnašanje nosilca, vključno z upogibno torzijsko stabilnostjo.
(5) Predstavljene so alternativne metode za nosilce s krožnimi odprtinami in sinusoidnimi odprtinami, pri katerih se sile in odpornosti izračunajo z inkrementi okoli ali vzdolž odprtin in so primerne za računalniške metode.
(6) Ta dokument se uporablja za vitkost pasnic, hw/tw, ki ne presega 121ε. Lokalni pregledi na in med sosednjimi odprtinami veljajo za vitkost pasnic do te meje. Materialni parameter ε je definiran v EN 1993-1-1:2022, 5.2.5 (2).
OPOMBA Meja 121ε je meja za razred 4 pasnice za jekleni profil z enakimi prirobnicami. Uporablja se kot priročna meja za uporabo tega dokumenta, vključno z monosimetričnimi profili.
(7) Ta dokument ne zajema utrujenosti. V primeru utrujenosti se uporablja EN 1993-1-9.
(8) Ta dokument ne zajema projektiranja za požar. Za projektiranje v primeru požara se uporablja EN 1993-1-2.
(9) Ta dokument ne zajema preverjanja stabilnosti elementov z odprtinami v pasnicah pod osno silo.
1.1.2 Oblike odprtin v pasnicah
(1) Različne oblike odprtin v pasnicah, ki so obravnavane v tem dokumentu, so prikazane na Sliki 1.1.
Slika 1.1 - Različne oblike odprtin v jeklenih nosilcih
1.1.3 Ojačane odprtine
(1) Ta dokument zajema tudi odprtine v pasnicah nosilcev, ki so ojačane z vzdolžnimi ojačitvami in/ali prečnimi ojačitvami na eni ali obeh straneh pasnice, glej Sliko 1.2.
OPOMBA Nacionalni dodatek lahko določi pravila za alternativne vrste ojačitev.
Slika 1.2 - Ojačitve odprtin v pasnicah nosilcev
1.2 Predpostavke
(1) Če ni posebej navedeno, veljajo EN 1990, serija EN 1991 in EN 1993-1-1.
(2) Projektne metode, navedene v EN 1993-1-13, so uporabne, če:
- je kakovost izvedbe določena v EN 1090-2, in
- so uporabljeni gradbeni materiali in proizvodi določeni v ustreznih delih serije EN 1993 ali v ustreznih specifikacijah materialov in proizvodov.

General Information

• Status: Not Published
• Public Enquiry End Date: 29-Jul-2026
• ICS: 91.010.30 - Technical aspects
• ICS: 91.080.13 - Steel structures
• Technical Committee: KON - Structures
• Current Stage: 4020 - Public enquire (PE) (Adopted Project)
• Start Date: 10-Jun-2026
• Due Date: 28-Oct-2026
• Ref Project: EN 1993-1-13:2024/prA1 - Eurocode 3 - Design of steel structures - Part 1-13: Beams with large web openings

Relations

• Amends: kSIST FprEN 1993-1-13:2023 - Eurocode 3 - Design of steel structures - Part 1-13: Beams with large web openings
• Effective Date: 20-Jan-2026

Standards Content (Sample)

SLOVENSKI STANDARD
01-julij-2026
Evrokod 3 - Projektiranje jeklenih konstrukcij - 1-13. del: Nosilci z velikimi
mrežnimi odprtinami
Eurocode 3 - Design of steel structures - Part 1-13: Beams with large web openings
Eurocode 3 - Bemessung und Konstruktion von Stahlbauten - Teil 1-13: Träger mit
großen Stegöffnungen
Eurocode 3 - Calcul des structures en acier - Partie 1-13 : Poutres avec grandes
ouvertures d'âme
Ta slovenski standard je istoveten z: EN 1993-1-13:2024/prA1
ICS:
91.010.30 Tehnični vidiki Technical aspects
91.080.13 Jeklene konstrukcije Steel structures
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

DRAFT
EUROPEAN STANDARD
EN 1993-1-13:2024
NORME EUROPÉENNE
EUROPÄISCHE NORM
prA1
May 2026
ICS 91.010.30; 91.080.13
English Version
Eurocode 3 - Design of steel structures - Part 1-13: Beams
with large web openings
Eurocode 3 - Calcul des structures en acier - Partie 1- Eurocode 3 - Bemessung und Konstruktion von
13 : Poutres avec grandes ouvertures d'âme Stahlbauten - Teil 1-13: Träger mit großen
Stegöffnungen
This draft amendment is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee CEN/TC 250.

This draft amendment A1, if approved, will modify the European Standard EN 1993-1-13:2024. If this draft becomes an
amendment, 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.

This draft amendment 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
© 2026 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 1993-1-13:2024/prA1:2026 E
worldwide for CEN national Members.

Contents Page
European foreword . 3
1 Modifications throughout the whole document . 4
2 Modifications to the Introduction . 4
3 Modification to Clause 1, “Scope” . 5
4 Modifications to Clause 3, “Terms and definitions” . 5
5 Modifications to Clause 4, “Basis of design” . 5
6 Modification to Clause 7, “Structural Analysis” . 6
7 Modifications to Clause 8, “Ultimate Limit States” . 6
8 Modification to Clause 9, “Serviceability limit states” . 8
European foreword
This document (EN 1993-1-13:2024/prA1:2026) 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 design
matters by CEN.
This document is currently submitted to the CEN Enquiry.
This document will amend EN 1993-1-13:2024.
NOTE Some modifications are purely editorial corrections to improve the quality of the document and these
will not be tagged in the consolidated publication, as noted after the modification.
The following main changes to EN 1993-1-13:2024 are included in the amendment:
— The definition of large web openings is clarified.
— The selection of the buckling curves for web-post buckling is improved, based on recent research
works and publications.
— The calculation method for end-post is improved, based on recent research works and publications.
— This amendment corrects technical and editorial points in EN 1993-1-13:2024 to increase the clarity
and user friendliness.
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.
1 Modifications throughout the whole document
Add “-1:2023+A1:2026” to the reference “EN 1990” in Clause 2 and update throughout the text when a
dated reference is given.
Add part number “-1” to the reference “EN 1990” and update throughout the text when an undated reference
is given.
2 Modifications to the Introduction
In 0.1, replace “— New parts are under development, e.g. Eurocode for design of structural glass”
with “— EN 19100 Eurocode 10 — Design of glass structures”.
In 0.1, add the following new list item: “— New parts are under development, e.g. Eurocode for design of
fibre-polymer composite structures and for design of tensioned membrane structures”.
In 0.2, replace in the first paragraph the reference to EN 1990 with “EN 1990-1 — Basis of structural and
geotechnical design — Part 1: New structures”.
In 0.2. replace the list of the various parts of EN 1993 with:
“EN 1993-1-1, Eurocode 3 — Design of Steel Structures — Part 1-1: General rules and rules for buildings;
EN 1993-1-2, Eurocode 3 — Design of Steel Structures — Part 1-2: Structural fire design;
EN 1993-1-3, Eurocode 3 — Design of Steel Structures — Part 1-3: Cold-formed members and sheeting;
NOTE Cold-formed hollow sections supplied according to EN 10219 (all parts) are covered in EN 1993-1-1.
EN 1993-1-4, Eurocode 3 — Design of Steel Structures — Part 1-4: Stainless steel structures;
EN 1993-1-5, Eurocode 3 — Design of Steel Structures — Part 1-5: Plated structural elements;
EN 1993-1-6, Eurocode 3 — Design of Steel Structures — Part 1-6: Strength and stability of shell structures;
EN 1993-1-7, Eurocode 3 — Design of Steel Structures — Part 1-7: Plate assemblies with elements under
transverse loads;
EN 1993-1-8, Eurocode 3 — Design of Steel Structures — Part 1-8: Joints;
EN 1993-1-9, Eurocode 3 — Design of Steel Structures — Part 1-9: Fatigue;
EN 1993-1-10, Eurocode 3 — Design of Steel Structures — Part 1-10: Material toughness and through-
thickness properties;
EN 1993-1-11, Eurocode 3 — Design of Steel Structures — Part 1-11: Tension components;
EN 1993-1-12, Eurocode 3 — Design of Steel Structures — Part 1-12: Additional rules for steel gr
...