SIST EN 1993-1-4:2007

SLOVENSKI STANDARD
SIST EN 1993-1-4:2007
01-marec-2007
1DGRPHãþD
SIST ENV 1993-1-4:2001
Evrokod 3: Projektiranje jeklenih konstrukcij - 1-4. del: Splošna pravila - Dodatna
pravila za nerjavna jekla
Eurocode 3 - Design of steel structures - Part 1-4: General rules - Supplementary rules
for stainless steels
Eurocode 3 - Bemessung und Konstruktion von Stahlbauten - Teil 1-4: Allgemeine
Bemessungsregeln - Ergänzende Regeln zur Anwendung von nichtrostender Stählen
Eurocode 3 - Calcul des structures en acier - Partie 1-4: Regles générales - Regles
supplémentaires pour les aciers inoxydables
Ta slovenski standard je istoveten z: EN 1993-1-4:2006
ICS:
77.140.20 Visokokakovostna jekla Stainless steels
91.010.30 7HKQLþQLYLGLNL Technical aspects
91.080.10 Kovinske konstrukcije Metal structures
SIST EN 1993-1-4:2007 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN 1993-1-4:2007

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SIST EN 1993-1-4:2007
EUROPEAN STANDARD
EN 1993-1-4
NORME EUROPÉENNE
EUROPÄISCHE NORM
October 2006
ICS 91.040.01; 91.080.10 Supersedes ENV 1993-1-4:1996
English Version
Eurocode 3 - Design of steel structures - Part 1-4: General rules
- Supplementary rules for stainless steels
Eurocode 3 - Calcul des structures en acier - Partie 1-4: Eurocode 3 - Bemessung und Konstruktion von
Règles générales - Règles supplémentaires pour les aciers Stahlbauten - Teil 1-4: Allgemeine Bemessungsregeln -
inoxydables Ergänzende Regeln zur Anwendung von nichtrostender
Stählen
This European Standard was approved by CEN on 9 January 2006.
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. 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 European Standard 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, 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
© 2006 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 1993-1-4:2006: E
worldwide for CEN national Members.

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SIST EN 1993-1-4:2007
EN 1993-1-4: 2006 (E)

Contents Page
Foreword 3
1 General 4
1.1 Scope 4
1.2 Normative references 4
1.3 Assumptions 5
1.4 Distinction between principles and application rules 5
1.5 Definitions 5
1.6 Symbols 5
2 Materials 6
2.1 Structural stainless steels 6
2.2 Bolts 8
2.3 Welding consumables 9
3 Durability 9
4 Serviceability limit states 10
4.1 General 10
4.2 Determination of deflections 10
5 Ultimate limit states 12
5.1 General 12
5.2 Classification of cross-sections 12
5.3 Resistance of cross-sections 17
5.4 Buckling resistance of members 18
5.5 Uniform members in bending and axial compression 20
5.6 Shear resistance 21
5.7 Transverse web stiffeners 21
6 Connection design 22
6.1 General 22
6.2 Bolted connections 22
6.3 Design of welds 23
7 Design assisted by testing 23
8 Fatigue 23
9 Fire resistance 23
Annex A [informative] Durability 24
A.1 Introduction 24
A.2 Types of corrosion 25
A.3 Levels of risk 27
A.4 Selection of materials 27
A.5 Design for corrosion control 30
A.6 Connections 31
Annex B [informative] Stainless steel in the work hardened condition 34
B.1 General 34
B.2 Work hardening from cold rolling 34
B.3 Work hardening from fabrication 34
Annex C [informative] Modelling of material behaviour 35
C.1 General 35
C.2 Material properties 35


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SIST EN 1993-1-4:2007
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Foreword

This European Standard EN 1993-1-4, Eurocode 3: Design of steel structures: Part 1-4 General Rules –
Supplementary rules for stainless steels, has been prepared by Technical Committee CEN/TC250 « Structural
Eurocodes », the Secretariat of which is held by BSI. CEN/TC250 is responsible for all Structural Eurocodes.

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 April 2007 and conflicting National Standards shall be withdrawn
at latest by March 2010.

This Eurocode supersedes ENV 1993-1-4.

According to the CEN-CENELEC Internal Regulations, the National Standard 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, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland and United Kingdom.


National Annex for EN 1993-1-4

This standard gives alternative procedures, values and recommendations with notes indicating where national
choices may have to be made. The National Standard implementing EN 1993-1-4 should have a National
Annex containing all Nationally Determined Parameters to be used for the design of steel structures to be
constructed in the relevant country.

National choice is allowed in EN 1993-1-4 through clauses:
– 2.1.4(2)
– 2.1.5(1)
– 5.1(2)
– 5.5(1)
– 5.6(2)
– 6.1(2)
– 6.2(3)

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SIST EN 1993-1-4:2007
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1 General
1.1 Scope

(1) This Part 1.4 of EN 1993 gives supplementary provisions for the design of buildings and civil
engineering works that extend and modify the application of EN 1993-1-1, EN 1993-1-3, EN 1993-1-5 and EN
1993-1-8 to austenitic, austenitic-ferritic and ferritic stainless steels.

NOTE 1: Information on the durability of stainless steels is given in Annex A.

NOTE 2: The execution of stainless steel structures is covered in EN 1090.

NOTE 3: Guidelines for further treatment, including heat treatment, are given in EN 10088.

1.2 Normative references

This following normative documents contain provisions which, through reference to this text, constitute
provisions of this European Standard. For dated references, subsequent amendments to or revisions of any of
these publications do not apply. However, parties to agreements based on this European Standard are
encouraged to investigate the possibility of applying the most recent editions of the normative documents
indicated below. For undated references, the latest edition of the normative document referred to applies.

EN 1990 Eurocode 0: Basis of structural design
EN 508-3 Roofing products from metal sheet. Specification for self-supporting products of steel,
aluminium or stainless steel sheet. Stainless steel;
EN 1090-2 Execution of steel structures and aluminium structures – Part 2: Technical requirements
for steel structures;
EN 1993-1-1 Design of steel structures: General rules and rules for buildings;
EN 1993-1-2 Design of steel structures: Structural fire design;
EN 1993-1-3 Design of steel structures: Cold formed thin gauge members and sheeting;
EN 1993-1-5 Design of steel structures: Plated structural elements;
EN 1993-1-6 Design of steel structures: Strength and stability of shell structures;
EN 1993-1-8 Design of steel structures: Design of joints;
EN 1993-1-9 Design of steel structures: Fatigue;
EN 1993-1-10 Design of steel structures: Material toughness and through-thickness properties;
EN 1993-1-11 Design of steel structures: Design of structures with tension components made of steel;
EN 1993-1-12 Design of steel structures: Additional rules for the extension of EN 1993 up to steel grades
S 700;
EN ISO 3506-1 Mechanical properties of corrosion resistant stainless steel fasteners – Part 1: Bolts,
screws and studs;
EN ISO 3506-2 Mechanical properties of corrosion resistant stainless steel fasteners – Part 2: Nuts
EN ISO 3506-3 Mechanical properties of corrosion resistant stainless steel fasteners – Part 3: Set screws
and similar fasteners under tensile tests;
EN ISO 7089 Plain washers - Normal series - Product grade A;
EN ISO 7090 Plain washers, chamfered - Normal series - Product grade A;
EN ISO 9445 Continuously cold-rolled stainless steel narrow strip, wide strip, plate/sheet and cut lengths
- Tolerances on dimensions and form
EN 10029 Specification for tolerances on dimensions, shape and mass for hot rolled steel plates
3 mm thick or above;

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EN 10052 Vocabulary of heat treatment terms for ferrous products;
EN 10088-1 Stainless steels – Part 1: List of stainless steels;
EN 10088-2 Stainless steels – Part 2: Technical delivery conditions for sheet/plate and strip for
general purposes;
EN 10088-3 Stainless steels - Part 3: Technical delivery conditions for semi-finished products, bars,
rods and sections for general purposes;
EN 10162 Cold rolled steel sections. Technical delivery conditions. Dimensional and cross-sectional
tolerances;
EN 10219-2 Cold formed welded structural sections of non-alloy and fine grain steels. Tolerances,
dimensions and sectional properties;
1.3 Assumptions

(1) In addition to the general assumptions of EN 1990 the following assumptions apply:
- fabrication and erection complies with EN 1090-2.

1.4 Distinction between principles and application rules

(1) The rules in EN 1990 clause 1.4 apply.
1.5 Definitions

(1) The rules in EN 1990 clause 1.5 apply.

(2) Unless otherwise stated, the vocabulary of treatment terms for ferrous products used in EN 10052
applies.
1.6 Symbols

In addition to those given in EN 1990, EN 1993-1-1, EN 1993-1-3, EN 1993-1-5 and 1993-1-8, the following
symbols are used:

f reduced value of bearing strength
u,red
E secant modulus of elasticity used for serviceability limit state calculations
s,ser
E secant modulus corresponding to the stress in the tension flange
s,1
E secant modulus corresponding to the stress in the compression flange
s,2
σ
serviceability design stress
1,Ed,ser
n coefficient

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2 Materials
2.1 Structural stainless steels
2.1.1 General

(1) The provisions given in this Part 1.4 should be applied only to design using austenitic, austenitic-ferritic
and ferritic stainless steels.

(2) The nominal values of the material properties given in 2.1.2 should be used as characteristic values in
structural design calculations.

(3) For further information about material properties reference should be made to EN 10088.

(4) The design provisions specified in this Part 1.4 are applicable for material of nominal yield strength f
y
2
up to and including 480 N/mm .

2
NOTE: Rules for the use of work hardened material with f > 480 N/mm are given in Informative
y
Annex B.

(5) The higher strength of other materials (see 2.1.2 and Annex B) may be taken into account in the design
provided that doing so is justified by appropriate tests in accordance with Section 7.

2.1.2 Material properties for stainless steel

(1) In design calculations the values should be taken as follows, independent of the direction of rolling:
- yield strength f : the nominal stress (0,2% proof stress) specified in Table 2.1;
y
- ultimate tensile strength f : the nominal ultimate tensile strength specified in Table 2.1.
u

(2) The ductility requirements in EN 1993-1-1, clause 3.2.2 also apply to stainless steels. Steels conforming
with one of the steel grades listed in Table 2.1 should be accepted as satisfying these requirements.

(3) For structural hollow sections, the strength values given in Table 2.1 for the relevant product form of the
base material (cold-rolled strip, hot rolled strip or hot rolled plate) should be used.

(4) Higher strength values derived from cold working the base material may be used in design provided they
are verified by tests on coupons taken from the structural hollow section in accordance with Section 7.

(5) For cold worked material, the material tests given in the material certificate required according to EN
1090, should be in such a direction that the strength values used in design are independent of the direction of
rolling or stretching.








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SIST EN 1993-1-4:2007
EN 1993-1-4: 2006 (E)

Table 2.1: Nominal values of the yield strength f and the ultimate tensile strength
y
1)
f for structural stainless steels to EN 10088
u

Product form
Bars, rods and
Cold rolled strip Hot rolled strip Hot rolled plate
sections
Type of
Nominal thickness t
stainless Grade
steel t ≤ 6 mm t ≤ 12 mm t ≤ 75 mm t ≤ 250 mm
f f f f f f f f
y u y u y u y u
2 2 2 2 2 2 2 2
N/mm N/mm N/mm N/mm N/mm N/mm N/mm N/mm
3) 3) 4) 4)
1.4003 280 450 280 450 250 450 260 450
Ferritic
3) 3) 4) 4)
1.4016 260 450 240 450 240 430 240 400
steels
1.4512 210 380 210 380 - - - -
1.4306 180 460
220 520 200 520 200 500
1.4307 175 450
1.4541
190 500
1.4301 230 540 210 520 210 520
1.4401
200 500
1.4404 530 530
240 220 220 520
1.4539 230 530
Austenitic
1.4571 540 540
steels
1.4432 200 500
240 550 220 550 220 520
1.4435
1.4311 290 550 270 550 270 550 270 550
1.4406 300 280 280
580 580 580
1.4439 290 270 270 280 580
1.4529 300 650 300 650 300 650
1.4547 320 650 300 650 300 650 300 650
1.4318 350 650 330 650 330 630 - -
2) 2)
Austenitic 1.4362 420 600 400 600 400 630 400 600
-ferritic

1.4462 480 660 460 660 460 640 450 650
steels
1)
The nominal values of f and f given in this table may be used in design without taking special account of
y u
anisotropy or strain hardening effects.
2)
t ≤ 160 mm
3)
t ≤ 25 mm
4)
t ≤ 100 mm

2.1.3 Design values of material coefficients

(1) The following values of the material coefficients may be assumed for the global analysis and in
determining the resistances of members and cross-sections:

- Modulus of elasticity, E:
2
E = 200 000 N/mm for the austenitic and austenitic-ferritic grades in Table 2.1 excluding grades
1.4539, 1.4529 and 1.4547
2
E = 195 000 N/mm for the austenitic grades 1.4539, 1.4529 and 1.4547
2
E = 220 000 N/mm for the ferritic grades in Table 2.1

E
- Shear modulus, G, where G =
2(1+ν )
- Poisson’s ratio in elastic stage, ν = 0,3


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Alternatively, stress-strain curves according to Annex C may be used for materials in the annealed condition to
describe the material behaviour.

(2) For calculating deflections in individual members, the secant modulus appropriate to the stress in the
member at the serviceability limit state may be used, see 4.2(5).

2.1.4 Fracture toughness

(1) The austenitic and austenitic-ferritic stainless steels covered in this Part 1.4 may be assumed to be
adequately tough and not susceptible to brittle fracture for service temperatures down to -40°C.

NOTE: Austenitic steels may also be used for temperatures below -40°C, but the requirements should be
determined for each particular case.

NOTE: See Annex A.5.3 concerning embrittlement due to contact with zinc in fire.

(2) For ferritic stainless steels, the rules in EN 1993-1-10 give guidance. Required testing temperature and
required CVN-values may be determined from Table 2.1 of EN 1993-1-10.

NOTE 1: Ferritic steels are not classified into sub-grades.

NOTE 2: The National Annex may provide further information on fracture toughness of ferritic stainless steels.

2.1.5 Through-thickness properties

(1) Guidance on the choice of through-thickness properties is given in EN 1993-1-10.

NOTE: The National Annex may provide further information on the choice of through thickness properties.

2.1.6 Tolerances

(1) The dimensional and mass tolerances of rolled steel sections, structural hollow sections and plates
should conform with the relevant product standard unless more severe tolerances are specified.

NOTE: For information about tolerances for thickness of cold rolled stainless steel, reference should be made to
EN ISO 9445: 2006. For plates see EN 10029

(2) For welded components the tolerances given in EN 1090-2 should be applied.

(3) For structural analysis and design, the nominal values of dimensions should be used except that the
design thickness of strips should be determined according to 3.2.4(3) of EN 1993-1-3.
2.2 Bolts
2.2.1 General

(1) Stainless steel bolts and nuts should conform with EN ISO 3506 - 1,2,3. Washers should be of stainless
steel and should conform with EN ISO 7089 or EN ISO 7090, as appropriate. The corrosion resistance of the
bolts should be equivalent to, or better than, the corrosion resistance of the parent material.

(2) The nominal yield strength f and ultimate tensile strength f for stainless steel bolts should be
yb ub
obtained from Table 2.2.

(3) Pending the issue of an appropriate European Standard, the specified properties should be verified using
a recognised quality control system, with samples from each batch of fasteners.



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SIST EN 1993-1-4:2007
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Table 2.2: Nominal values of f and f  for stainless steel bolts
yb ub
Property class Yield strength Ultimate tensile strength
Material
to Range of sizes f f
yb ub
groups
2 2
EN ISO 3506 N/mm N/mm
Austenitic 50 ≤ M 39  210 500
and
70 ≤ M 24 450 700
austenitic-
80 ≤ M 24 600 800
ferritic

2.2.2 Preloaded bolts

NOTE: High strength bolts made of stainless steel should not be used as preloaded bolts designed for a specific slip
resistance, unless their acceptability in a particular application can be demonstrated from test results.
2.2.3 Other types of mechanical fastener

(1) Requirements for other types of mechanical fasteners are given in EN 1993-1-3.

2.3 Welding consumables

(1) General requirements for welding consumables are given in EN 1993-1-8.

(2) In addition to the requirements of EN 1993-1-8, the welding electrodes should be capable of producing a
weld with a corrosion resistance that is adequate for the service environment, provided that the correct welding
procedure is used.

(3) The welding electrodes may be assumed to be adequate if the corrosion resistance of the deposited metal
and weld metal is not less than that of the material to be welded.

NOTE: Professional advice is recommended on the selection of welding procedure for jointing stainless steels


3 Durability

(1) The requirements for durability given in Section 4 of EN 1993-1-1 should also be applied for stainless
steels.

(2) An appropriate grade of stainless steel should be selected according to the corrosion resistance required
for the environment in which the structural members are to be used.

NOTE: Guidance on the selection of materials for corrosion resistance is given in Annex A.

(3) In cosmetic applications, the possible minor changes in surface appearance that might take place as a
result of dirt deposits (which in adverse circumstances can create crevices and lead to surface micro-pitting)
should also be taken into account. A suitable corrosion-resistant grade of stainless steel should be used to
ensure that only superficial surface attack takes place within the design life of the component.

NOTE: Surface aspect features of hot rolled plates are described in EN 10163.

(4) If necessary, a suitable cleaning regime should be specified to maintain surface appearance.

(5) Although, under benign atmospheric exposure conditions, the requirements given in (3) can be satisfied
by most stainless steels, expert advice should be sought if stainless steel is required to be exposed to
environments that contain chemicals, including atmospheres associated with certain industrial processes, in
swimming pool buildings, sea water and salt spray from road de-icing or the like.


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NOTE: Additional information on design for corrosion control is given in Annex A.

4 Serviceability limit states
4.1 General

(1) The requirements for serviceability given in Section 7 of EN 1993-1-1 should be applied for stainless
steels.

(2) Deflections in members should be estimated in accordance with 4.2.
4.2 Determination of deflections

(1) The effects of the non-linear stress-strain behaviour of stainless steels, and the effectiveness of the cross-
section, should be taken into account in estimating deflections.

NOTE: Guidance for the description of the non-linear material behaviour of annealed material is given in
Informative Annex C.

(2) The basic requirements for serviceability limit states are given in clause 3.4 of EN 1990.

NOTE: EN 1990 gives the appropriate combinations of actions to use in the following situations:
 - for calculating deflections under permanent and/or variable actions;
 - when long term deformations due to shrinkage, relaxation or creep need to be considered;
 - if the appearance of the structure or the comfort of the user or functioning of machinery are being
considered.

(3) The effective cross-section may conservatively be based on effective widths of compression elements in
Class 4 cross-sections determined using 5.2.3. Alternatively, the more accurate method in 4.4(4) of EN 1993-1-
5 may be used.

(4) In the case of members subject to shear lag, the effective cross-section may be based on effective widths
determined using 3.2 in EN 1993-1-5.

(5) Deflections should be estimated using the secant modulus of elasticity E determined taking account
s,ser
of the stresses in the member under the load combination for the relevant serviceability limit state and the
orientation of the rolling direction. If the orientation of the rolling direction is not known, or cannot be ensured,
then the value for the longitudinal direction should be used. Alternatively, the FE-methods given in Annex C of
EN 1993-1-5 may be used with the description of the non-linear material behaviour given in Annex C of this
document.

(6) The value of the secant modulus of elasticity E may be obtained from:
s,ser

(E + E )
s,1 s,2
E =     (4.1)
s,ser
2

where:

E is the secant modulus corresponding to the stress σ in the tension flange;
s,1 1
E is the secant modulus corresponding to the stress σ in the compression flange.
s,2 2

(7) The values of E and E for the appropriate serviceability design stress σ and rolling direction
s,1 s,2 i,Ed,ser
may be estimated using:


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EN 1993-1-4: 2006 (E)

E
E =    (4.2)
s,i n
 
E
σ
i, Ed,ser
 
1 + 0,002
 
σ f
i, Ed,ser y
 
with:
i = 1 or 2.

(8) The value of the coefficient n may be taken from Table 4.1.

NOTE: Annex C gives a method for evaluating n for grades other than those listed in Table 4.1.

(9) As a simplification, the variation of E along the length of the member may be neglected and the
s,ser
minimum value of E for that member (corresponding to the maximum values of the stresses σ and
s,ser 1,Ed,ser
σ in the member) may be used throughout its length.
2,Ed,ser

Table 4.1: Values of n

Coefficient n

Steel grade
Longitudinal Transverse
direction direction
1.4003 7 11
1.4016 6 14
1.4512 9 16
1.4301
1.4306
1.4307 6 8
1.4318
1.4541
1.4401
1.4404
1.4432
7 9
1.4435
1.4539
1.4571
1.4462 5 5
1.4362


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5 Ultimate limit states
5.1 General

(1) The provisions given in Sections 5 and 6 of EN 1993-1-1 should be applied for stainless steels, except
where modified or superseded by the special provisions given in this Part 1.4.

(2) The partial factors γ as defined in 2.4.3 of EN 1993-1-1 are applied to the various characteristic values
M
of resistance in this section as follows, see Table 5.1.


Table 5.1: Partial factors

Resistance of cross-sections to excessive yielding including γ
M0
local buckling
Resistance of members to instability assessed by member
γ
M1
checks
Resistance of cross-sections in tension to fracture
γ
M2
Resistance of bolts, rivets, welds, pins and plates in bearing
γ
M2

NOTE: γ values may be determined in the National Annex. The following values are recommended
M

γ = 1,1
M0
γ = 1,1
M1
γ = 1,25
M2

(3) No rules are given for plastic global analysis.

NOTE: Plastic global analysis should not be used unless there is sufficient experimental evidence to ensure that
the assumptions made in the calculations are representative of the actual behaviour of the structure. In particular
there should be evidence that the joints are capable of resisting the increase in internal moments and forces due to
strain hardening.

(4)P Joints subject to fatigue shall also satisfy the principles given in EN 1993-1-9.

(5) Where members may be subjected to significant deformation, account may be taken of the potential for
enhanced strength gained through the work hardening properties of austenitic stainless steel. Where this work
hardening increases the actions resisted by the members, the joints should be designed to be consistent with the
increased member resistance, especially where capacity design is required.
5.2 Classification of cross-sections
5.2.1 Maximum width-to-thickness ratios

(1) The provisions for design by calculation given in this Part 1.4 may be assumed to apply to cross-sections
within the dimensional limits given in EN 1993-1-3, except that the overall width-to-thickness ratios b/t and
h/t as defined in EN 1993-1-3 should not exceed 400, see Figure 5.1.

(2) If visual distortion of flat elements of the cross-section are unacceptable under the serviceability loading,
a limit of b/t ≤ 75 may be applied.



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Figure 5.1: Maximum width-to-thickness ratios
5.2.2 Classification of compression elements

(1) Compression elements of cross-sections should be classified as Class 1, 2 or 3 depending upon the limits
specified in Table 5.2. Those compression elements that do not meet the criteria for Class 3 should be
classified as Class 4 elements.

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Table 5.2 (sheet 1 of 3): Maximum width-to-thickness ratios for compression parts

Internal compression parts
h c
c c
Axis of bending

t t t

t t
t
c c c
Axis of bending



Part subject to Part subject to
Class Part subject to bending and compression
bending compression
f f f
y y y
Stress
distribution + + +
αc
in parts
c c c
(compression -
-
-
positive)
f f f
y y y


308ε
when α > 0,5 : c / t ≤
13α −1
1 c / t ≤ 56,0ε c /t ≤ 25,7ε
28ε
when α ≤ 0,5 : c /t ≤
α
320ε
when α > 0,5 : c / t ≤
13α −1
c / t ≤ 58,2ε c /t ≤ 26,7ε
2
29,1ε
when α ≤ 0,5 : c /t ≤
α
f f f
y y
y
Stress
+ +
distribution
c c c
+
in parts
2
c/
-
(compression -

positive)
ψ
f f
y y



c /t ≤ 15,3ε k
σ
c / t ≤ 74,8ε c / t ≤ 30,7ε
3
For k see EN 1993-1-5
σ
0,5
Grade 1.4301 1.4401 1.4462
 
235 E
2
f (N/mm ) 210 220 460
ε =
y
 
f 210 000
 
y 1,03 1,01 0,698
  ε
Note: For hollow sections, c may conservatively be taken as (h-2t) or (b-2t).

14

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SIST EN 1993-1-4:2007
EN 1993-1-4: 2006 (E)

Table 5.2 (sheet 2 of 3): Maximum width-to-thickness ratios for compression parts

Outstand flanges
c
t
c
t

Section Part subject to Part subject to bending and compression
Class
type compression
Tip in compression Tip in tension
f
y
Stress c c
α α
+
distribution in f y f y
+
+
–
parts
c
– –
(compression

f y f y
c c
positive)

10ε
10ε
Cold
c / t ≤
c /t ≤ 10ε c / t ≤
formed
α α α
1
9ε
9ε
c /t ≤
Welded c / t ≤ 9ε c /t ≤
α α
α
10,4ε
10,4ε
Cold
c / t ≤
c /t ≤ 10,4ε c / t ≤
formed
α α α
2
9,4ε
9,4ε
c / t ≤ 9,4ε c / t ≤
Welded c /t ≤
α α α
f
y f
Stress
y
+
f y
+
distribution in
+
–
–
parts
c
–
(compression c

c
positive)

Cold
c / t ≤ 11,9ε
c /t ≤ 18,1ε k  For k see EN 1993-1-5
σ
σ
formed
3
Welded c /t ≤ 16,7ε k  For k see EN 1993-1-5
c / t ≤ 11ε
σ
σ
0,5
Grade 1.4301 1.4401 1.4462
 
235 E
2
f (N/mm ) 210 220 460
ε = y
 
f 210 000
 y 
  1,03 1,01 0,698
ε


15

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SIST EN 1993-1-4:2007
EN 1993-1-4: 2006 (E)

Table 5.2 (sheet 3 of 3): Maximum width-to-thickness ratios for compression parts


Angles

h h
Does not apply to angles in
b b
Refer also
...