prEN 17149-1
(Main)Railway applications - Strength assessment of railway vehicle structures - Part 1: General
Railway applications - Strength assessment of railway vehicle structures - Part 1: General
This document supports the other standards in the EN 17149 series, in order to ensure consistency of terminology across the series. It describes the basic terms and definitions as well as general procedures for strength assessments of rail vehicle structures that are manufactured, operated and maintained in accordance with standards valid for rail system applications.
This document is applicable to all kinds of rail vehicles.
The assessment procedure is restricted to ferrous materials and aluminium.
This document does not define design load cases.
This document is not applicable for corrosive conditions or elevated temperature operation in the creep range.
Bahnanwendungen - Festigkeitsnachweis von Schienenfahrzeugstrukturen - Teil 1: Allgemeine Anforderungen für Festigkeitsnachweise (Statik und Ermüdung)
Dieses Dokument beschreibt die grundlegenden Begriffe und Definitionen sowie allgemeine Verfahren zum Festigkeitsnachweis von Schienenfahrzeugstrukturen, die nach den für den Einsatz in Bahnsystemen gültigen Normen hergestellt, betrieben und instandgehalten werden.
Das Nachweisverfahren der Normenreihe beschränkt sich auf eisenhaltige Werkstoffe und Aluminium.
Dieses Dokument legt keine Bemessungslastfälle fest.
Dieses Dokument ist nicht anzuwenden für Korrosionszustände oder Betrieb bei erhöhter Temperatur im Kriechbereich.
Dieses Dokument ist für alle Arten von Schienenfahrzeugen anwendbar.
Applications ferroviaires - Évaluation de la résistance des structures de véhicule ferroviaire - Partie 1 : Généralités
Le présent document spécifie les termes et définitions de base ainsi que des procédures générales d'évaluation de la résistance des structures de véhicules ferroviaires qui sont fabriquées, exploitées et maintenues conformément aux normes applicables aux applications ferroviaires.
La procédure d'évaluation se limite aux matériaux ferreux et à l'aluminium.
Le présent document ne définit pas de cas de charge de conception.
Le présent document ne s'applique pas en cas de conditions corrosives ou de conditions d'exploitation à une température élevée dans la plage de fluage.
Le présent document s'applique à tous les types de véhicules ferroviaires.
Železniške naprave - Ocenjevanje odpornosti konstrukcije železniških vozil - 1. del: Splošno
General Information
Standards Content (Sample)
SLOVENSKI STANDARD
oSIST prEN 17149-1:2021
01-september-2021
Železniške naprave - Ocenjevanje odpornosti konstrukcije železniških vozil - 1.
del: Splošno
Railway applications - Strength assessment of railway vehicle structures - Part 1:
General
Bahnanwendungen - Festigkeitsnachweis von Schienenfahrzeugstrukturen - Teil 1:
Allgemeine Anforderungen für Festigkeitsnachweise (Statik und Ermüdung)
Applications ferroviaires - Évaluation de la résistance des structures de véhicule
ferroviaire - Partie 1 : Généralités
Ta slovenski standard je istoveten z: prEN 17149-1
ICS:
45.060.01 Železniška vozila na splošno Railway rolling stock in
general
oSIST prEN 17149-1:2021 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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oSIST prEN 17149-1:2021
DRAFT
EUROPEAN STANDARD
prEN 17149-1
NORME EUROPÉENNE
EUROPÄISCHE NORM
June 2021
ICS 45.060.01
English Version
Railway applications - Strength assessment of railway
vehicle structures - Part 1: General
Applications ferroviaires - Évaluation de la résistance Bahnanwendungen - Festigkeitsnachweis von
des structures de véhicule ferroviaire - Partie 1 : Schienenfahrzeugstrukturen - Teil 1: Allgemeine
Généralités Anforderungen für Festigkeitsnachweise (Statik und
Ermüdung)
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee
CEN/TC 256.
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, Turkey 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
© 2021 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 17149-1:2021 E
worldwide for CEN national Members.
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Contents Page
European foreword . 3
Introduction . 4
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
3.1 General terms and strength related terms . 5
3.2 Material related terms . 7
3.3 Terms related to welding . 8
3.4 Fatigue related terms . 13
4 Symbols and abbreviations . 17
5 Linear stress determination . 23
5.1 General. 23
5.2 Parent material . 23
5.3 Welded joints . 23
5.3.1 General. 23
5.3.2 Evaluation point . 24
5.4 Determination of stresses by test . 27
6 Structural strength behaviour modes . 28
6.1 Instability . 28
6.2 Collapse . 28
6.3 Rupture . 28
6.4 Significant permanent deformation . 28
6.5 Low cycle fatigue . 28
6.6 High cycle fatigue . 28
7 Partial factors for covering uncertainties . 28
7.1 General. 28
7.2 Partial factor for loads γ . 29
L
7.3 Partial factor for the component strength γ . 29
M
7.3.1 General. 29
7.3.2 Consequence of failure . 30
7.3.3 Degree of the validation process . 30
8 Strength assessment procedure . 30
9 Tolerances and uncertainties in respect to structural strength . 30
9.1 General. 30
9.2 Influence of manufacturing on material quality. 31
9.3 Influence of manufacturing on dimensional tolerances . 31
9.4 Loads . 31
9.5 Validation process . 31
Bibliography . 32
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European foreword
This document (prEN 17149-1:2021) has been prepared by Technical Committee CEN/TC 256 “'Railway
applications”, the secretariat of which is held by DIN.
This document is currently submitted to the CEN Enquiry.
This document is part of the series EN 17149 Railway applications — Strength assessment of railway
vehicle structures, which consists of the following parts:
• Part 1: General
• Part 3: Fatigue strength assessment based on cumulative damage
The following part is under preparation:
• Part 2: Static strength assessment
This document has been prepared under a mandate given to CEN by the European Commission and the
European Free Trade Association.
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Introduction
The structural design of rail vehicle structures depends on the loads they are subject to and the
characteristics of the materials they are manufactured from. This document provides the basic procedure
and criteria for a pragmatic method to be applied for strength assessments.
Because of multiple use cases and different lifetime requirements this document does not define load
cases and does not define in which cases or for which kinds of rail vehicles a strength assessment is to be
applied.
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1 Scope
This document describes the basic terms and definitions as well as general procedures for strength
assessment of rail vehicle structures that are manufactured, operated and maintained according to
standards valid for rail system applications.
The assessment procedure is restricted to ferrous materials and aluminium.
This document does not define design load cases.
This document is not applicable for corrosive conditions or elevated temperature operation in the creep
range.
This document is applicable to all kinds of rail vehicles.
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.
EN 17343:2020, Railway applications — General terms and definitions
ISO/TR 25901-1:2016, Welding and allied processes — Vocabulary — Part 1: General terms
3 Terms and definitions
For the purposes of this document, the terms and definitions, symbols and abbreviations given in
ISO/TR 25901-1:2016, EN 17343:2020 and the following terms and definitions, symbols and
abbreviations apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
• IEC Electropedia: available at https://www.electropedia.org/
• ISO Online browsing platform: available at https://www.iso.org/obp
3.1 General terms and strength related terms
3.1.1
rail vehicle structure
combination of all load carrying parts of a rail vehicle including its substructures and components
3.1.2
corrosive condition
condition in which an operation in corrosive environment causes effects on the material strength values
or loss of material
Note 1 to entry: It is presupposed that in railway applications an adequate corrosion protection avoids corrosive
conditions for the structure. Corrosive conditions are therefore out of the scope of this document.
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3.1.3
finite element analysis
FEA
numerical method for obtaining approximate solutions of partial differential equations subject to
boundary conditions
Note 1 to entry: Finite element analysis is a kind of numerical calculation.
[SOURCE: ISO 18459:2015, 3.6, modified – Note 1 to entry has been changed]
3.1.4
partial factor
factor considering uncertainties of loads (forces), material, model, geometry, manufacturing, and/or
degree of validation
Note 1 to entry: In some of the referenced documents, the partial factor is described with terms as “safety factor”
as in EN 12663 series and EN 13749 or partial factor for variable actions (e.g. loads or forces) and for material,
model and geometric uncertainties as in ISO 2394.
3.1.5
design load
load or combination of loads which a structure is designed to withstand, incorporating any necessary
allowances to account for uncertainties in their values
3.1.6
representative load
load or combination of loads derived from standards, simulations or tests, covering a known set of
influences, acting as a basis for the derivation of design load
3.1.7
utilisation
ratio between the acting value – calculated or measured - and the allowable limit value
Note 1 to entry: The values are usually expressed as terms of loads, stresses or strains.
3.1.8
safety category
classification defining the consequences of failure of the single structural detail with respect to the effects
on persons, facilities and the environment
[SOURCE: EN 15085-1:2007+A1:2013, 3.17, modified – 'classification' has been added, 'welded joint'
has been substituted by 'structural detail']
3.1.9
exceptional load
infrequent load which represents the extremal loads or combination of loads for the relevant operation
conditions
Note 1 to entry: Exceptional load is also described with terms 'static load', 'static design load' or 'proof load'.
3.1.10
ultimate load
extremal design load that the structure withstands without rupture or collapse
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3.1.11
fatigue load
frequent load or combination of loads which represents the normal relevant operation conditions
3.2 Material related terms
3.2.1
brittle material
material that has a permanent elongation at rupture of A < 6 %
Note 1 to entry: Cast iron with lamellar graphite (GJL) and cast aluminium (AC) are examples for brittle material.
3.2.2
ductile material
material, which is not brittle
3.2.3
plastification
load-indicated inelastic strain response from a stress level above the material yield strength
3.2.4
significant permanent deformation
plastification which infringes the functionality of a component or the structure
3.2.5
structural failure
loss of load-carrying capacity in the structure
3.2.6
local yielding
plastic strain in a local area small enough so that no significant permanent deformation occurs
3.2.7
fully operational
completely functional, working and as designed to serve a defined purpose under specific conditions
Note 1 to entry: The term fully operational implies no significant permanent deformation and no need for repair.
3.2.8
survival probability
probability that the structural detail will not fail within a specified operating time
Note 1 to entry: Survival probability is related to the single sided probability of the distribution function.
[SOURCE: ISO 11994:1997, 7.1, modified – 'product' has been changed into 'structural detail'; Note 1
to entry has been added]
3.2.9
shear stress
component of stress coplanar with a material cross section
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3.2.10
direct stress
component of a stress tensor which is not shear stress, not indicating a specific orientation
Note 1 to entry: This term is also known as ‘normal stress’. The term ‘direct stress’ is chosen to avoid confusion
with an oriented stress component normal (perpendicular) to the weld.
3.2.11
membrane stress
average direct stress which is uniform across the thickness of a plate or shell
3.2.12
bending stress
stress in a shell or plate-like part of a component with linear distribution across the thickness
3.2.13
secondary bending stress
bending stress in a weld throat caused by membrane stress and eccentricity between the weld throat and
connected plate midpoint e
W
3.2.14
residual stress
permanent internally balanced stresses in a structure, caused by manufacturing processes (e.g., rolling,
cutting or welding)
3.3 Terms related to welding
3.3.1
parent material
material of a structure outside of welded joints
[SOURCE: ISO/TR 25901-1:2016, 2.1.1.5, modified – extension to any material which is not welded]
3.3.2
transverse to the weld
perpendicular to the feature under consideration (e.g., the weld toe)
Note 1 to entry: Stresses and strains longitudinal to the weld are indicated with an index '⊥'.
Note 2 to entry: The stress direction definition ‘transverse to the weld’ is shown in Figure 1.
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Figure 1 — Stress direction definition transverse to the weld
3.3.3
longitudinal to the weld
aligned with (parallel to) the feature under consideration (e.g., the weld toe)
Note 1 to entry: The stress direction definition ‘longitudinal to the weld’ is shown in Figure 2.
Note 2 to entry: For the assessment of the weld end the direction ‘longitudinal to the weld’ is orthogonal to the
direction ‘transverse to the weld’.
Note 3 to entry: Stresses and strains longitudinal to the weld are indicated with an index 'II'.
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Key
1 stop-/start-position
Figure 2 — Stress direction definition longitudinal to the weld
3.3.4
linear misalignment
axial offset from the nominal geometry of plates within a welded joint
Note 1 to entry: The definition ‘linear misalignment’ is shown in Figure 3.
Key
1 linear misalignment
Figure 3 — Linear misalignment
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3.3.5
angular misalignment
angular deviation from the nominal geometry of plates within a welded joint
Note 1 to entry: The definition ‘angular misalignment’ is shown in Figure 4.
Key
1 angular misalignment
Figure 4 — Angular misalignment
3.3.6
eccentricity
e
axial offset of plates due to the nominal geometry within a welded joint
Note 1 to entry: The definition ‘eccentricity’ is shown in Figure 5.
Key
e eccentricity
Figure 5 — Example for eccentricity
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3.3.7
effective throat thickness
a
dimension that is responsible for carrying the load which is dependent on the shape and penetration of
the weld
Note to entry 1: For T-joints, the effective throat thickness equals the minimum distance from the root to the weld
surface as shown in Figure 6.
[SOURCE: EN ISO 17659:2004, 3.20, modified – The symbol a has been added.]
Key
a effective throat thickness
c root gap length
e eccentricity between the midpoint of the weld throat and the connected plate
W
t plate thickness
Figure 6 — Effective throat thickness in a T-joint with HY weld and with additional fillet weld
3.3.8
relevant thickness
dimensions to be used for the assessment of a welded joint
Note 1 to entry: The dimensions depend on the type of assessment (static strength or fatigue strength) or
potential crack initiation point at fatigue strength assessments (e.g. weld root or weld toe failure).
3.3.9
weld performance class
performance requirements of the welded joint with respect to weld quality requirements and weld
inspection requirements
Note 1 to entry: The weld performance class is abbreviated by “CP” (class of performance).
[SOURCE: EN 15085-1:2007+A1:2013, 3.2]
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3.3.10
weld inspection class
inspections to be carried out for a given weld with respect to the frequency and the type of inspection
(e.g., volumetric, surface or visual) as defined by the weld performance class
Note 1 to entry: The weld inspection class is abbreviated by “CT” (class of testing)
[SOURCE: EN 15085-1:2007+A1:2013, 3.3]
3.3.11
non- destructive testing
NDT
act of determining the suitability of some material or component for its intended purpose using
techniques that do not affect its serviceability
[SOURCE: ISO/TR 25901-1:2016, 2.2.4.1 – modified: The abbreviation 'NDT' has been added; 'to' has
been deleted.]
3.4 Fatigue related terms
3.4.1
fatigue
process of initiation and propagation of cracks through a structural part due to action of fluctuating
stresses
3.4.2
fatigue action
time varying repeated loading events which introduce a stress into a structural component
3.4.3
fatigue stress
stress caused by fatigue action
3.4.4
stress cycle
pattern of variation of stress at a point defined by the cycle counting method and consisting of a change
in stress between a minimum (trough) and maximum (peak) values and back again
3.4.5
mean stress
mean value of the maximum and the minimum alternating stress in a cycle
3.4.6
amplitude
half the algebraic difference between the maximum and the minimum during a cycle
3.4.7
stress range
two times of the stress amplitude
3.4.8
stress ratio
R
ratio of the minimum to the maximum algebraic value of the stress in a particular stress cycle
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3.4.9
stress spectrum
fatigue stresses including the partial factor for actions (e.g., loads) and relevant to the fatigue strength
assessment
3.4.10
stress range block
part of stress spectrum with constant stress range
3.4.11
S-N curve
experimentally derived, quantitative relationship between the fatigue strength and the number of cycles
for a structural detail, corresponding to a specific survival probability of failure
Note 1 to entry: S-N curves are usually represented by a series of (log Δσ) – (log N) values or of (log Δτ) – (log N)
values.
3.4.12
constant amplitude
signal with non-varying amplitudes
3.4.13
variable amplitude
signal with varying amplitudes
3.4.14
fatigue strength
structural detail’s resistance to fatigue actions expressed in terms of a S-N curve for a survival probability
= 97,5 %
of P
s
3.4.15
design value of the component strength
strength of a structural detail considering the partial factor for the component strength γ
M
3.4.16
reference value of the fatigue strength
Δσ , Δτ
C C
6
fatigue strength for a welded joint related to N = 2×10 cycles and a stress ratio of R = 0,5
C
3.4.17
component fatigue strength
Δσ , Δτ
R R
fatigue strength considering the specific design details at a stress ratio of R = −1
3.4.18
strength at the knee point
Δσ , Δτ
D D
component fatigue strength at the knee point of the S-N curve N
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3.4.19
endurance limit
stress range below which no fatigue damage will occur under constant amplitude stress conditions
Note 1 to entry: This is also known as ‘constant amplitude fatigue limit’.
3.4.20
proportional stresses
principal stresses or stress components with constant directions and constant ratios of their values for
time varying loads
3.4.21
non-proportional stresses
principal stresses or stress components with non-constant directions and non-constant ratios of their
values for time varying loads
3.4.22
damage-equivalent stress range
constant amplitude stress range which produces the same utilisation to that resulting from a variable
amplitude stress spectrum
3.4.23
damage sum
sum of damage, caused by fatigue action
3.4.24
cumulative damage sum
linear cumulative damage summation based on the rule devised by Palmgren and Miner of the fatigue
damage due to all cycles in a stress spectrum
3.4.25
cumulative damage rule
method for estimating fatigue life under variable amplitude loading from the constant amplitude stress-
life (S-N)
Note 1 to entry: Often referred to as damage accumulation hypothesis, Miner’s rule or Palmgren-Miner rule.
3.4.26
cut-off limit
stress range below which the stress cycles are considered to be non-damaging under variable amplitude
conditions
3.4.27
elementary version of Miner’s rule
damage hypothesis applying Miner’s rule with an S-N curve with one constant exponent under
consideration of a restricted admissible damage sum
3.4.28
modified version of Miner’s rule
damage hypothesis applying Miner’s rule with a modified S-N curve with a higher exponent after a knee
point and under consideration of a restricted admissible damage sum
Note 1 to entry: This version of Miner's rule is also known as ‘Haibach Modification’.
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3.4.29
consistent version of Miner’s rule
damage hypothesis applying Miner’s rule within an iterative procedure determining a modified S-N curve
to obtain an admissible damage sum
Note 1 to entry: This version of Miner's rule is also known as ‘Miner konsequent’.
3.4.30
nominal stress
stress in a component adjacent to a potential crack location calculated in accordance with elasticity
theory excluding all stress concentration effects (e.g., welds, openings, thickness changes)
3.4.31
modified nominal stress
nominal stress including macro-geometric effects
Note 1 to entry: The macro-geometric effects are the stress-raising effects caused by the macro-geometry in the
vicinity of the welded joints (e.g. concentrated load effects, misalignment, eccentricity) but disregarding stress
raising effects of the weld joint itself.
3.4.32
structural stress
surface value of linearly distributed stress across the section thickness adjacent to a welded detail or
linear extrapolation on the surface to the weld toe, both considering the effects of a structural
discontinuity
Note 1 to entry: Structural stress is also referred to as geometric stress. The structural stress determined by
linear extrapolation on the surface to the weld toe is also referred to as the hot spot stress.
Note 2 to entry: The linear stress distribution includes the effects of gross structural discontinuities
(e.g. presence of an attachment, aperture, change of cross-section, misalignment, intersection of members) and
distortion-induced bending moments. However, it excludes the notch effects of local structural discontinuities (e.g.
weld toe, weld end) which give rise to nonlinear stress distributions across the section thickness.
3.4.33
notch stress
calculated stress for a notch of welded joint with a certain assumed notch radius
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4 Symbols and abbreviations
Symbol Description Part Clause
A permanent elongation at rupture 2 7.2.3.2
A stress spectrum shape factor 7.4.2
3
eq
a effective throat thickness 1 3.3.7
a mean stress sensitivity parameter A.2.1
m 3
a constant for the surface roughness factor 5.1.4.1
R,σ 3
b gap between plates of a welded joint Table D.25,
3
5
b distance from the weld toe or the root to the evaluation point 5.3.2
1
EP
b width of the heat-affected zone 5.1.3.2
HAZ 2
b
mean stress sensitivity parameter A.2.1
m 3
b constant for the surface roughness factor 5.1.4.1
R 3
c root gap length 1 3.3.7
D cumulative damage sum of the stress spectrum 7.4.4
it 3
D admissible damage sum 7.4.3
3
m
D damage sum limit 5.2.9
m,min 3
E Young's modulus
e eccentricity as axial offset of plates due to the nominal geometry within 1 3.3.6
a welded joint
e eccentricity between the midpoint of the weld throat and the connected 1 3.3.7
W
plate
f anisotropy factor for rolled sheets and extrusions 3 5.1.3.1
A
f enhancement factor for bending 3 E.2.3
bend
f compression strength factor 2 5.1.2.2
C
f
enhancement factor for the weld inspection class 3 5.2.8
CT
f eccentricity effect factor for membrane stresses 3 F.2.2
e
f mean stress factor for direct stresses 3 Annex A
m,σ
f mean stress factor for shear stresses 3 Annex A
m,τ
f enhancement factor for post-weld improvement 3 5.2.6
post
f quality level factor 3 5.2.7
QL
f fatigue strength factor for castings 3 5.1.6
R,C
f fatigue strength factor for direct stresses 3 5.1.5
R,σ
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Symbol Description Part Clause
f ratio between the fatigue strength of shear stress and the one of direct 3 5.1.5
R,τ
stress
f residual stress factor for direct s
...
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