EN 17149-3:2024

SLOVENSKI STANDARD
oSIST prEN 17149-3:2023
01-maj-2023
Železniške naprave - Ocenjevanje odpornosti konstrukcije železniških vozil - 3.
del: Ocena odpornosti proti utrujenosti na podlagi kumulativne škode
Railway applications - Strength assessment of rail 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
oSIST prEN 17149-3:2023 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

oSIST prEN 17149-3:2023
prEN 17149-3:2023 (E)
Contents Page
European foreword . 6
Introduction . 7
1 Scope . 8
2 Normative references . 8
3 Terms and definitions . 8
4 Stress determination . 9
4.1 General. 9
4.2 Parent material . 9
4.3 Welded joints . 9
4.3.1 Modified nominal stresses . 9
4.3.2 Structural stresses and notch stresses . 9
5 Fatigue strength . 9
5.1 Parent material . 9
5.1.1 General. 9
5.1.2 Component fatigue strength Δσ and Δτ . 10
R R
5.1.3 Material properties . 10
5.1.4 Design Parameters . 11
5.1.5 Fatigue strength factors for direct stresses f and for shear stresses f . 13
R,σ R,τ
5.1.6 Correction factor for casting fR,C . 14
5.1.7 S-N curves and methods of cumulative damage rule . 15
5.2 Welded joints . 16
5.2.1 General. 16
5.2.2 Fatigue classes Δσ and Δτ . 16
C C
5.2.3 Component fatigue strength Δσ and Δτ . 17
R R
5.2.4 Influence of thickness f and bending . 17
thick
5.2.5 Residual stress factors f and f . 18
res,σ res,τ
5.2.6 Enhancement factor for post-weld improvement f . 18
post
5.2.7 Quality level factor f . 19
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 . 20
5.3 Determination of the fatigue strength of parent material and welded joints by
laboratory tests . 22
6 Partial factors covering uncertainties . 23
6.1 General. 23
6.2 Partial factor for loads γ . 23
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 . 24
M,S
6.3.3 Partial factor for the inspection during maintenance γ . 25
M,I
6.3.4 Partial factor for the degree of the validation process γ . 26
M,V
7 Procedure of the fatigue strength assessment based on cumulative damage
calculation . 26
oSIST prEN 17149-3:2023
prEN 17149-3:2023 (E)
7.1 General . 26
7.2 Stress determination . 27
7.3 Determination of the design stress spectrum . 27
7.3.1 Conditioning . 27
7.3.2 Stress history adjustment . 27
7.3.3 Counting . 28
7.3.4 Mean stress adjustment . 28
7.3.5 Omission . 29
7.4 Damage calculation for each single stress component . 29
7.4.1 General . 29
7.4.2 Determination of stress spectrum shape factor A . 30
eq
7.4.3 Determination of admissible damage sum D . 30
m
7.4.4 Determination of the utilization for a single stress component U . 31
c
7.5 Assessment of fatigue strength . 32
7.6 Critical plane approach . 33
Annex A (informative) Procedure for determination of mean stress factors for parent
material and welded joints . 35
A.1 General . 35
A.2 Mean stress sensitivity . 35
A.2.1 Parent material . 35
A.2.2 Welded joints . 36
A.3 Determination of mean stress factors . 36
Annex B (informative) Specification example for permissible volumetric defects in steel,
iron and aluminium castings . 40
B.1 General . 40
Annex C (informative) Material factors for parent material . 41
Annex D (normative) Fatigue classes Δσ and Δτ for welded joints based on the nominal
C C
stress approach . 43
D.1 Explanation of the tables for fatigue classes . 43
D.1.1 General . 43
D.1.2 Number in accordance with EN 15085-3:2022, Table B.1 . 43
D.1.3 Sketch of the joint . 43
D.1.4 Joint specific requirements . 44
D.1.5 Potential crack initiation point . 44
D.1.6 Feasibility for inspection . 44
D.1.7 Relevant thickness for the assessment of a welded joint . 44
D.1.8 Material . 44
D.1.9 Fatigue classes Δσ and Δτ . 44
C C
D.1.10 Exponent m and number of cycles at the knee point of the S-N curve N . 45
D
D.1.11 Thickness correction exponents n n and n . 45
σ,┴, σ,|| τ
D.1.12 Lower limit of the plate thickness for the thickness correction t . 45
min
D.1.13 Parameter α used for the determination of f . 45
bend bend
oSIST prEN 17149-3:2023
prEN 17149-3:2023 (E)
D.2 Tables of fatigue classes for welded joints . 46
D.3 Determination of fatigue strength based on comparative notch case models . 81
Annex E (informative) Thickness and bending influence on nominal and structural stress
approaches for welded joints . 82
E.1 General. 82
E.2 Influence quantities . 83
E.2.1 Thickness correction factor f . 83
thick
E.2.2 Enhancement factor for bending f . 84
bend
E.3 Methods for application of f in the assessment process . 85
bend
E.3.1 General. 85
E.3.2 General ratio method . 85
E.3.3 Constant ratio method . 86
E.3.4 Comparative notch case model method. 86
Annex F (informative) Stress adjustment due to joint geometry for welded joints for nominal
...