oSIST prEN 17149-3:2021

Railway applications - Strength assessment of railway vehicle structures - Part 3: Fatigue strength assessment based on cumulative damage

This European Standard specifies a procedure for fatigue strength assessment of rail vehicle structures based on cumulative damage.
It is part of a series of standards that specifies procedures for strength assessments of structures of rail vehicles that are manufactured, operated and maintained according to standards valid for railway applications.
This document is applicable for variable amplitude load data with total number of cycles higher than 10000 cycles.
An endurance limit approach is outside the scope of this European Standard.
The assessment procedure of the series is restricted to ferrous materials and aluminium.
This document series does not define design load cases.
This document series is not applicable for corrosive conditions or elevated temperature operation in the creep range.
This series of standards is applicable to all kinds of rail vehicles, however it does not define in which cases  a fatigue strength assessment using cumulative damage is to be applied.

Bahnanwendungen - Festigkeitsnachweis von Schienenfahrzeugstrukturen - Teil 3: Betriebsfestigkeitsnachweis

Applications ferroviaires - Évaluation de la résistance des structures de véhicule ferroviaire - Partie 3 : Évaluation de la résistance à la fatigue basée sur la méthode des dommages cumulés

Le présent document spécifie la procédure à appliquer pour l'évaluation de la résistance à la fatigue des structures de véhicules ferroviaires selon la méthode des dommages cumulés.
Il fait partie d'une série de normes qui spécifient les procédures d'évaluation de la résistance des structures de véhicules ferroviaires qui sont fabriquées, exploitées et entretenues conformément aux normes applicables aux applications ferroviaires.
Le présent document est applicable pour des données de charge à amplitude variable avec un nombre total de cycles supérieur à 10 000 cycles.
La méthode d'endurance limite ne relève pas du domaine d'application du présent document.
La procédure d'évaluation spécifiée dans cette série de normes se limite aux matériaux ferreux et à l'aluminium.
Cette série de normes ne définit pas de cas de charge de conception.
Cette série de normes ne s'applique pas en cas de conditions corrosives ou d'exploitation à une température élevée dans la plage de fluage.
Cette série de normes est applicable à tous les types de véhicules ferroviaires. Toutefois, elle ne définit pas dans quels cas il est nécessaire de réaliser une évaluation de la résistance à la fatigue selon la méthode des dommages cumulés.

Železniške naprave - Ocenjevanje odpornosti konstrukcije železniških vozil - 3. del: Ocena odpornosti proti utrujenosti na podlagi kumulativne škode

General Information

• Status: Not Published
• Public Enquiry End Date: 15-Sep-2021
• ICS: 45.060.01 - Railway rolling stock in general
• Technical Committee: IŽNP - Reilway applications
• Current Stage: 4020 - Public enquire (PE) (Adopted Project)
• Start Date: 01-Jul-2021
• Due Date: 18-Nov-2021
• Completion Date: 16-Sep-2021
• Ref Project: prEN 17149-3 - Railway applications - Strength assessment of railway vehicle structures - Part 3: Fatigue strength assessment based on cumulative damage

Standards Content (Sample)

SLOVENSKI STANDARD
01-september-2021
Železniške naprave - Ocenjevanje odpornosti konstrukcije železniških vozil - 3.
del: Ocena odpornosti proti utrujenosti na podlagi kumulativne škode
Railway applications - Strength assessment of railway vehicle structures - Part 3: Fatigue
strength assessment based on cumulative damage
Bahnanwendungen - Festigkeitsnachweis von Schienenfahrzeugstrukturen - Teil 3:
Betriebsfestigkeitsnachweis
Applications ferroviaires - Évaluation de la résistance des structures de véhicule
ferroviaire - Partie 3 : Évaluation de la résistance à la fatigue basée sur la méthode des
dommages cumulés
Ta slovenski standard je istoveten z: prEN 17149-3
ICS:
45.060.01 Železniška vozila na splošno Railway rolling stock in
general
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

DRAFT
EUROPEAN STANDARD
NORME EUROPÉENNE
EUROPÄISCHE NORM
June 2021
ICS 45.060.01
English Version
Railway applications - Strength assessment of railway
vehicle structures - Part 3: Fatigue strength assessment
based on cumulative damage
Applications ferroviaires - Évaluation de la résistance Bahnanwendungen - Festigkeitsnachweis von
des structures de véhicule ferroviaire - Partie 3 : Schienenfahrzeugstrukturen - Teil 3:
Évaluation de la résistance à la fatigue basée sur la Betriebsfestigkeitsnachweis
méthode des dommages cumulés
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 17149-3:2021 E
worldwide for CEN national Members.

Contents Page
European foreword . 5
Introduction . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 7
4 Stress determination . 8
4.1 General. 8
4.2 Parent material . 8
4.3 Welded joints . 8
4.3.1 Modified nominal stresses . 8
4.3.2 Structural stresses and notch stresses . 8
5 Fatigue strength . 8
5.1 Parent material . 8
5.1.1 General. 8
5.1.2 Component fatigue strength Δσ and Δτ . 9
R R
5.1.3 Material properties . 9
5.1.4 Design Parameters . 11
5.1.5 Fatigue strength factors for normal and shear stresses f and f . 13
R,σ R,τ
5.1.6 Fatigue strength factor for castings f . 13
R,C
5.1.7 S-N curves and methods of cumulative damage rule . 15
5.2 Welded joints . 17
5.2.1 General. 17
5.2.2 Reference values of the fatigue strength Δσ and Δτ . 17
C C
5.2.3 Component fatigue strength Δσ and Δτ . 18
R R
5.2.4 Influence of thickness f and bending . 18
thick
5.2.5 Residual stress factor f and f . 19
res,σ res,τ
5.2.6 Enhancement factor for post-weld improvement f . 19
post
5.2.7 Quality level factor f . 20
QL
5.2.8 Enhancement factor for the weld inspection class f . 20
CT
5.2.9 S-N curves and methods of cumulative damage rule . 21
5.3 Determination of the fatigue strength of parent material and welded joints by
laboratory tests . 23
6 Partial factors for covering uncertainties . 23
6.1 General. 23
6.2 Partial factor for loads γ . 24
L
6.3 Partial factor for the component fatigue strength γ . 24
M
6.3.1 General. 24
6.3.2 Partial factor for the consequence of failure γ . 25
M,S
6.3.3 Partial factor for the inspection during maintenance γ . 26
M,I
6.3.4 Partial factor for the degree of the validation process γ . 26
M,V
prEN 17149:2021 (E)
7 Procedure of the fatigue strength assessment based on cumulative damage
calculation . 27
7.1 General . 27
7.2 Stress determination . 28
7.3 Determination of the stress spectrum . 28
7.3.1 Conditioning . 28
7.3.2 Stress history adjustment . 28
7.3.3 Counting . 28
7.3.4 Mean stress adjustment . 29
7.3.5 Omission . 29
7.4 Damage calculation for each single stress component . 30
7.4.1 General . 30
7.4.2 Determination of stress spectrum shape factor A . 31
eq
7.4.3 Determination of admissible damage sum D . 31
m
7.4.4 Determination of cumulative damage sum D and scaling factor x to reach the
it it
admissible damage sum . 31
7.5 Assessment of fatigue strength . 33
Annex A (informative) Procedure for determination of mean stress factors for parent
material and welded joints . 34
A.1 General . 34
A.2 Mean stress sensitivity . 34
A.2.1 Parent material . 34
A.2.2 Welded joints . 35
A.3 Determination of mean stress factors . 35
Annex B (informative) Specification example for permissible volumetric defects in castings
of steel, iron and aluminium . 39
B.1 General . 39
Annex C (informative) Material factors for parent material . 41
Annex D (normative) Reference values of the fatigue strength Δσ and Δτ for welded
C C
joints based on the nominal stress approach . 42
D.1 Explanation of the tables for reference values of the fatigue strength . 42
D.1.1 General . 42
D.1.2 Weld seam type according to EN 15085-3, Table B.1 . 42
D.1.3 Sketch of the joint . 42
D.1.4 Joint specific requirements . 43
D.1.5 Potential crack initiation point .
...