CEN/TR 17039:2017

SLOVENSKI STANDARD
01-maj-2017
äHOH]QLãNHQDSUDYH7HKQLþQRSRURþLORRUHYL]LML(1
Railway applications - Technical Report about the revision of EN 14363
Bahnanwendungen - Fachbericht zur Überarbeitung der EN 14363
Applications ferroviaires - Rapport technique de la révision de la norme EN 14363
Ta slovenski standard je istoveten z: CEN/TR 17039:2017
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.

CEN/TR 17039
TECHNICAL REPORT
RAPPORT TECHNIQUE
February 2017
TECHNISCHER BERICHT
ICS 45.060.01
English Version
Railway applications - Technical Report about the revision
of EN 14363
Applications ferroviaires - Rapport technique de la Bahnanwendungen - Fachbericht zur Überarbeitung
révision de la norme EN 14363 der EN 14363

This Technical Report was approved by CEN on 12 January 2017. It has been drawn up by the Technical Committee CEN/TC 256.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2017 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN/TR 17039 E
worldwide for CEN national Members.

Contents Page
European foreword . 5
1 Scope . 6
2 Members of the different drafting groups for the revision of EN 14363 . 6
3 Changes to the scope . 7
3.1 Scope extension . 7
3.2 Limitation . 7
3.3 Clarification . 8
3.4 Shifted to other sections . 8
4 Fault modes . 8
4.1 What was changed? . 8
4.2 Why was it changed? . 9
4.3 Comments raised in the CRM process and how they were addressed . 9
5 Load conditions for testing . 9
6 First stage assessment . 10
6.1 General . 10
6.2 Safety against derailment on twisted track . 10
6.3 Safety against derailment under longitudinal compressive forces in S-shaped curves . 12
6.4 Evaluation of the torsional coefficient of a car body . 12
6.5 Determination of displacement characteristics . 12
6.6 Loading of the diverging branch of a switch . 13
6.7 Running safety in curved crossings for vehicles with small wheels . 14
7 Statistical analysis and multiple regression . 14
7.1 Background . 14
7.2 Relationship of assessment parameters and input variables . 14
7.3 Assessment methods . 16
7.4 Assessment by statistical methods in EN 14363 . 16
7.4.1 General . 16
7.4.2 One-dimensional method . 16
7.4.3 Two-dimensional method . 24
7.4.4 Multiple regression . 28
7.5 Regression assumptions . 31
8 Recalculation of Y/Q (7.6.2.2.5) . 32
8.1 What was changed . 32
8.2 Why was it changed . 33
8.3 Any references to useful background . 33
8.4 What were the options, what was rejected and why? . 33
9 Track loading parameters . 36
10 Rail surface damage quantity T . 36
qst
10.1 What was changed . 36
10.2 Why was it changed . 36
10.3 Approach . 37
10.4 Derivation and definition of T . 38
qst
10.5 Measurable quantities . 39
10.6 Limit values . 39
10.7 Verification from tests . 40
11 Replacing of limit values of ride characteristics by informative guidance for
assessment . 40
11.1 General . 40
11.2 Removing limit values for quasi-static lateral acceleration . 41
11.3 Revision of accelerometer positions in the car body of freight vehicles . 42
12 Track geometric quality and coordination with WG 28 . 42
12.1 Background . 42
12.2 Joint Survey Group WG 10 / WG 28 . 44
12.3 DynoTRAIN project . 45
12.4 Use of 50 % and / or 90 % levels. 45
12.5 Changes from EN 14363:2005 and UIC 518:2009 . 45
12.6 Speed range used for Track Quality assessment . 46
12.7 Wavelength Ranges . 46
12.8 Requirements in different zones . 47
12.9 Topics discussed but not changed . 47
13 Contact conditions . 47
13.1 Equivalent conicity . 47
13.1.1 Summary of requirements of EN°14363:2005 . 47
13.1.2 Summary of requirements of UIC Leaflet 518:2009 . 48
13.1.3 Changes in EN 14363:2016 . 48
13.2 Background information about investigations carried out in the DynoTRAIN project . 49
13.3 Radial steering index (RSI) . 54
13.3.1 Summary of requirements of EN°14363:2005 . 54
13.3.2 Summary of requirements of UIC Leaflet 518:2009 . 54
13.3.3 Changes in EN°14363:2016 . 55
13.3.4 Background information about the radial steering index . 55
14 Special vehicles . 58
15 Simulation . 59
15.1 General . 59
15.2 Model validation . 60
15.2.1 Principle of model validation . 60
15.2.2 Evaluations to carry out model validation . 60
15.2.3 Independent review . 61
15.2.4 Validation proposal from DynoTRAIN . 61
15.2.5 Efficiency of the usage of stationary tests . 62
15.3 Fields and conditions for application of simulation . 62
15.3.1 Introduction. 62
15.3.2 Definitions of reference and modified vehicle . 62
15.3.3 Scope of permitted modifications . 63
15.3.4 Requirements regarding the modification of a validated model . 63
15.3.5 Evaluation of estimated values . 64
15.3.6 Application field: Extension of the range of test conditions . 64
15.3.7 Application field: Approval of vehicle modification . 64
15.3.8 Application field: Approval of new vehicles by comparison with a reference vehicle . 65
15.3.9 Application field: Investigation of dynamic behaviour in case of fault modes . 65
15.4 Input data for simulation . 65
15.4.1 Introduction. 65
15.4.2 Track layout . 65
15.4.3 Track irregularity data . 66
15.4.4 Frequency / wavelength content . 66
15.4.5 Requirements for variation in input conditions . 66
16 Extension of acceptance (Annex U). 66
17 Topics discussed but postponed for future revisions . 68
17.1 General . 68
17.2 Y/Q . 68
17.3 T . 68
qst
17.4 B and B . 68
qst max
17.5 Y . 68
a,max
17.6 Introduction of high frequency contents to the Q-force limits . 68
17.7 Track geometry . 69
17.8 Compatibility with track conditions outside the test conditions . 69
17.9 WHEEL RAIL Geometric contact conditions . 69
17.10 Cyclic top . 70
17.11 Over-speed and over Cant deficiency testing . 70
17.12 General points . 70
18 Influence of the revision of EN 14363 on current TSIs . 71
18.1 General . 71
18.2 Letter to ERA . 71
18.3 Annex 1 to letter to ERA . 71
Annex A (informative) Guideline for presentation of results from multiple regression . 76
A.1 Introduction and purpose . 76
A.2 Principles . 76
A.3 Example . 77
Bibliography . 80

European foreword
This document (CEN/TR 17039:2017) has been prepared by Technical Committee CEN/TC 256
“Railway applications”, the secretariat of which is held by DIN.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
1 Scope
EN 14363 contains a lot of requirements which were modified during the last revision. The scope was
also extended. It was found in the working group, that many decisions that were taken to formulate
these modifications need to be documented to improve understanding and to allow a later further
development if practice of applications shows the necessity. The work for the revision was organised in
8 subgroups. Many of these subgroups recorded the way to the proposals in reporting templates, which
were used for the editing work. Afterwards discussion was ongoing in WG 10 and in the enquiry
process. This available information needs to be summarised and presented in a common format in
order to allow people not involved in the discussions to understand the background of the
modifications.
2 Members of the different drafting groups for the revision of EN 14363
Bold X means group leader
Normal X means group
member
HS (DE) X X  X X  X X
SZ (DE) X X    X
MW (SE)  X X X  X
BE (UK)   X   X
PD (FR)  X X X   X
AC (UK) X X   X X  X
JS (AT)  X X  X X X
VB (FR)  X    X
AB (FR)     X
VB (DE)  X    X
JC (FR)  X
OC (FR)       X
RD (FR)        X
HG (NO)  X X    X
AH (AT)  X X    X
TH (CZ)     X   X
M J (UK)    X
AK (AT)      X
TK (DE)  X X  X   X
RK (DE)     X X  X
NK (IT)   X   X
DL (FR)  X   X  X
8.1 Editing
8.2 Test Conditions
8.3 Track Quality,
Contact Conditions
8.4 Special vehicles
8.5 Stationary Tests
8.6 Simulation,
Extension of acceptance
8.7 Track Loading
8.8 Ride Characteristics
Bold X means group leader
Normal X means group
member
JÖ (SE)       X
MO (UK)     X   X
OP (CH)  X X  X X
UR (CH)  X     X
AS (CH)  X
RW (UK)  X  X
MZ (DE)   X  X  X
3 Changes to the scope
3.1 Scope extension
The standard was further developed from a pure collection of test specifications to a description of the
process for assessment of running characteristics. In addition, it also contains specifications on an
informative basis not necessarily to be used for the acceptance process.
The new process also includes the use of simulations. The requirements were further developed
starting from the requirements specified in UIC 518:2009 and EN 15827 and refined in discussions
inside WG 10 and its relating subgroups and in a second step by the DynoTRAIN research project.
The scope was extended to freight vehicles with nominal static vertical wheelset forces up to 250 kN
(previously handled in EN 15687). Also the inclusion of vehicles intended for operation with cant
deficiencies above 165 mm (previously handled in EN 15686) was covered by the new requirement to
specify the combination of admissible speed and admissible cant deficiency. Additionally the loading
conditions for the assessment have been defined more precisely.
Further a hint to a set of recommended values for admissible cant deficiencies to be chosen for broad
international approval was included. It replaces the fixed requirements made for conventional vehicles
in the previous version of the standard.
In order to close the open points in the Rolling Stock TSIs about track geometric quality and the
achievability of the combination of the specified test conditions during on-track tests, the concept of
defined target test conditions and the assessment of achieved test results against target test conditions
was developed.
Further, it needed to be stated that the standard also contains quantities and dependencies that are not
directly used for acceptance purposes, but for example for purposes of validation of simulation models
or determination of operating conditions outside the reference conditions.
3.2 Limitation
In order to prevent misuse of the standard for non-railway and non-standard gauge vehicles, it was
better described what needs to be considered when using it “by analogy” for such vehicles.
8.1 Editing
8.2 Test Conditions
8.3 Track Quality,
Contact Conditions
8.4 Special vehicles
8.5 Stationary Tests
8.6 Simulation,
Extension of acceptance
8.7 Track Loading
8.8 Ride Characteristics
To clarify the limits of the scope, it was stated that the strength of the vehicle and mounted parts,
passengers and train crew vibration exposure, comfort, load security and effects of cross wind are out
of the scope of this standard – as well as the quantification of track deterioration or track fatigue.
3.3 Clarification
It was found that the old wording needed clarification: “Testing for acceptance of vehicles is based on
some reference conditions of track. If these are not respected on certain lines, appropriate measures
will be taken (speed modifications, additional tests, etc.).”
The discussion in WG 10 showed that it was not possible to specify the underlying reference conditions
by exact boundaries. The only way for clarification was to:
— state that all vehicles which were successfully assessed are able to be operated on tracks complying
with EN 13803;
— describe the current state of the art in order to allow the EIM (European Infrastructure Managers)
to continue to use their implemented process for operation under demanding track conditions in
the future (for example on lines with curve radii below 250 m).
This includes two notes explaining why vehicles can also be operated safely outside the target test
conditions. A third note clarifies that the methods of this standard may also be applied to determine
operating rules under infrastructure conditions that are more severe than the target test conditions.
In this context, it was also stated that the document contains target test conditions for the geometric
track quality, as they have been adjusted compared to the previous version of the standard.
As the target test conditions for stability testing were changed with respect of the target conditions of
the TEN (Trans European Network), it was necessary to clarify, that the equivalent conicity to be
included in the stability assessment might be higher in some national systems for the time being before
the infrastructure target conditions are met. In this context, it was found necessary to state in a note
that such national requirements do not necessarily have to include the maximum occurring values of
equivalent conicity. This makes it possible to find practical test conditions and it reflects also testing at
overspeed and that vehicles assessed as stable are in most cases far below the limit values.
3.4 Shifted to other sections
The allowances
— to deviate from the rules laid down if evidence can be furnished that safety is at least the equivalent
to that ensured by complying with these rules and
— of variations from the defined conditions as specified by the article 7.1 of Directive 91/440 of EC
which were stated in the scope of the 2005 version are now described more detailed in a separate
clause (4). It is now stated that in case of deviations, these shall be reported, explained and taken
into account when assessing the safety.
4 Fault modes
4.1 What was changed?
The explicit requirement on testing with deflated air springs was removed.
A new subclause 5.2.2 “Fault modes” and a new subclause in Annex T (Simulation of on-track tests),
T.2.5 (Investigation of dynamic behaviour in case of fault modes) was introduced.
4.2 Why was it changed?
When testing with deflated air springs was introduced in UIC 518, air springs were a relative novelty in
railway vehicles. Since then much experience has been gained and they are now very common and it
was felt inappropriate to specify a test for the specific fault mode of deflated air springs, while many
other possible fault modes were overlooked, such as faulty yaw dampers or failing active components.
In EN 14363:2005 faulty yaw dampers were also specifically mentioned in parallel to deflated air
springs. A more open approach was also indicated in EN 14363:2005, this idea is further developed in
the present revision of EN 14363.
It was therefore appropriate to further develop the writing in EN 14363:2005 and require a similar –
more open – methodology for dynamics assessment. It is impossible in a standard like EN 14363 to
foresee every possible relevant fault mode to assess since these will differ from vehicle to vehicle. Also,
the technical development makes it necessary to adopt a methodology that can be used for future
systems not known today.
It was not clear in EN 14363:2005 at what speed fault modes were to be tested, also not what test
extent to apply. Therefore, a large variation of testing practice has evolved from country to country
making it more difficult to follow a principle of testing in one country for acceptance in many.
With the introduction of simulations, it was also necessary to define under what conditions simulations
can be used to assess fault modes.
Some important principles were clarified:
— Due to probability reasons, assessment of a fault mode is limited to running safety parameters,
speed up to V and cant deficiency up to I .
adm adm
— Independent fault modes shall be tested/ simulated independently, unless the analysis points out
the combined fault is necessary to be assessed.
— The safety factor λ does not need to be derived for fault modes, see U.2.
4.3 Comments raised in the CRM process and how they were addressed
In the comment phase there were discussions, not on the principles but on the writing to make it clear
yet open enough for its purpose.
The comments revealed concerns that the new approach would lead to requirements for additional
testing which was not the intention. The intention was only to provide a framework to assess the
relevant fault modes which may not be the same for each and every vehicle type.
To handle these concerns, modifications were made, where one of the most important changes was to
clarify that potentially catastrophic failures of conventional mechanical parts are managed by the
design and maintenance regime of the vehicle, and hence do not need to be additionally assessed.
5 Load conditions for testing
There were a number of different references to loading condition which were not consistent and clearly
enough specified in the 2005 edition. It was concluded that for clarity, loading definitions used in
EN 15663 would be the reference load cases, but where the loading conditions specified in EN 15663
are inappropriate then details for specific loading cases will be given where these apply. This is
particularly the case with extreme loads. Testing in the context of EN 14363 does not relate to extreme
cases, nor has it been used in the corresponding tests prior to the introduction of EN 14363 in European
rail administrations. As a result, the test loading conditions to be used apply the relevant normal
loading for the operation of the tested vehicle.
Another aspect was that extreme conditions could lead to outliers in the statistical sample that cannot
be handled by the statistical approach of EN 14363.
Further it was agreed that the load cases to be used for stationary and on-track testing should be as
consistent as possible and that for some tests not all of the load conditions need to be investigated.
For long distance and high speed trains without obligatory seat reservation it was found inadequate to
test them only with occupied seats. Therefore, the load case “Design mass in working order” was
adjusted by taking into account 2 P/m in standing areas. It was found that this was already state of the
art.
SNCF members of WG 10 explained, that vehicles for RER in Paris were always tested in a loaded
condition taking into account up to 700 kg/m in standing areas, referring to EN 15663:2009, 6.2.
WG 10 decided that in future and if necessary, such a case should be handled as a notified national
technical rule (NNTR). This will remove the possibility of uncertainty about when extreme loads are
required to be considered and under which circumstances they are to be applied.
For handling the necessary fuel consumption during testing, some practical rules were specified,
assuming that they will not be used to influence test results systematically. For locomotives, that
normally have big fuel tanks, it was taken into account that measured values of track loading might vary
too much if the full range of fuel consumption is used during testing. Therefore, the acceptable range
was restricted to the upper third.
Another practical rule was created to specify the handling of loads that can be collected and/or
distributed or spread along the railway track during operation.
The definitions of the load cases “empty” and “loaded” were concentrated in subclause 5.3.2 giving
common rules for all tests described in EN 14363.
6 First stage assessment
6.1 General
In the 2005 edition, this topic was covered by Clause 4 'Stationary tests'. Concern was expressed that
since some of the tests specified in the chapter were not in fact stationary but included movement of the
test vehicle the title could therefore cause some confusion. As a result the title became the subject of
much discussion, a suggestion to change the name to 'quasi-static tests' was rejected because this could
also cause confusion since the term 'quasi-static' does not translate from English directly into other
languages. As a result, the title of the clause was changed to 'first stage assessment' to reflect that
generally the assessments that are identified in this chapter are carried out on a vehicle before the on-
track testing is carried out.
The term assessment has been adopted to recognise that it is not always necessary to carry out physical
tests to demonstrate the performance of a vehicle. In certain circumstances that are defined in the text
of the clause, other means of demonstration of the performance is possible.
6.2 Safety against derailment on twisted track
Before the introduction of internationally accepted approval, the various approvals were carried out by
each national authority. This process was generally carried out by the national railway. There was
concern that a proper definition of the testing conditions did not exist, e.g. details such as tolerances on
track gauge, track curvature etc. This was particularly so with the inclusion of additional institutions,
who had not previously carried out these tests but were now permitted to perform the testing. A
definition of the test conditions was therefore required. After inquiries with the railway test bodies,
where they still existed, it became clear that there was no definitive definition of the test conditions that
had historically been carried out, either arising from the UIC tests or for national requirements. In
addition, the tests carried out in the past did not include records of the actual test conditions of the
track, such as track gauge, deviations from the 'nominal' values of track curvature or installed cant. As a
result the current text does not define limits to be applied, but does require the track conditions to be
recorded in the future. When sufficient data are available, it is the intention to specify limits that shall
be applied that are both practical and relevant.
There was some confusion about the compatibility of the test conditions for each of the three test
methods in the 2005 edition, the coefficient of friction was not consistent between the methods. The
reason for the difference could not be determined although the three methods all derive from the
original work carried out within the ERRI B55 project. As a result of the possible misinterpretation, it
has been made clear that each method shall be considered separately.
As with the definition of track condition, investigations were carried out to determine the signal
processing that had been applied to data recordings in the past. No information could be found about
what processing was applied and so nothing could be specified with any confidence, again the
processing that is applied in future test is required to be recorded with the intention that when
sufficient data is available requirements will be formulated.
Method 1 as defined in the 2005 edition has caused some confusion. The requirements included a
double requirement, with both the Y/Q limit and the flange climb wheel lift limit Δz, specified as
acceptance criteria. This has been changed by removing the Y/Q limit with the Δz remaining as the
acceptance requirement. However, the requirement is to record the Y/Q value during the tests, although
this is not an acceptance criterion.
With current techniques it is not credible to analyse the interface conditions that influence the Δz value
with certainty and so it is not permitted to carry out analysis of any changes to a vehicle that could
affect Δz value. As a result any vehicle that differs from the tested vehicle shall be retested.
However, it is possible by using the recorded Y/Q values to analyse both the originally tested vehicle's
performance and the performance of a vehicle that has undergone a change to the significant
parameters of a vehicle using the method 2 criteria.
Method 2 now recognises that in the event of a change to a significant parameter of a vehicle (such as
change in vertical stiffness) a vehicle type that has been previously accepted using method 2 can now be
analysed to assess the effect of the change. The analysis can be made by comparing the performance of
the original vehicle with that of the changed vehicle.
Method 3 In the 2005 edition, the twist criteria for the test was intended to be identical to that used in
method 1, to maintain a consistent test condition. This resulted in a different test condition compared to
the original criteria for method 3 which is defined in the GB RSSB document GM RT 2141.
A comment (GB 792) proposed to relax the bogie test twist of method 3 from 7 ‰ to 6,67 ‰ in order
to be consistent with the origin of the requirement (GM/RT 2141, issue 3). A detailed analysis showed,
that the original application of GM/RT 2141, issue 3, leads to a vehicle twist depending also on the bogie
+
wheel base 2a :
+
3,33‰⋅−6m 2a
( )
*
g 3,33‰+
GMRT
*
2a
=
Key
Y vehicle test twist in mm/m
2a* running gear distance in m
Figure 1 — Vehicle test twist as a function of vehicle dimensions
As this is lower than or roughly equal as the vehicle test twist specified in EN 14363:2005 (see
**
Diagram) g 3 ‰+ 20 mm / 2a , it was decided, to keep the vehicle test twist specification from
EN
EN 14363:2005 in combination with the slightly relaxed bogie test twist from GM/RT 2141 as it was
proposed by the comment. Compared to the twist conditions of method 1 and method 2 this test
condition remains roughly equal or more demanding, depending on the geometry of the vehicle to be
tested.
To fit the two curves for bogie twist and vehicle twist, the limitation for the application of 6,67 ‰
needed to be increased from 5 m to 5,45 m.
6.3 Safety against derailment under longitudinal compressive forces in S-shaped
curves
The tests referenced in this chapter, and detailed in EN 15839, reflect the requirements developed in
the UIC leaflet 530-2. The reference has been changed from UIC 530-2 to EN 15839 and EN 14033-1 for
special vehicles.
6.4 Evaluation of the torsional coefficient of a car body
This evaluation has been included since it is relevant to the tests for safety against derailment under
longitudinal compressive forces in S-shaped curves and some of the tests for safety against derailment
on twisted track. It was derived from ERRI B12/DT 135, Annex E and was refined in order to remove
the influence of the roll moment from the results.
6.5 Determination of displacement characteristics
This chapter replaced the subclause 4.3 “Sway characteristics” in EN 14363:2005. This replacement and
the inclusion of this evaluation has been made in conjunction with CEN/TC 256 WG 32, at their request.
This evaluation is included because the tests described are generally performed when the other tests
described in the First Stage Assessment are carried out. Only the tests are described, the data obtained
is used in the processes of EN 15273. Details have been removed from the main text and placed in
Annex D of the revised EN.
=
The term “flexibility coefficient” has replaced “roll coefficient” to relate directly to the EN 15273 series.
6.6 Loading of the diverging branch of a switch
For some railways the determination of a vehicle's performance is required when negotiating a
diverging branch. The characteristics of the track at a diverging branch differ between countries and as
a result it is not possible to define testing or acceptance criteria. Nevertheless, a methodology has been
agreed for the process to be followed when there is a need to determine the performance when
negotiating this track feature. Much of the work in developing the technique was carried out by DB but
the limit values that were established during this work relates only to the DB situation. For other
situations where the features of a diverging branch differ from the DB case, it would be necessary to
carry out specific studies to determine specific limits for that case.
The following provides background about the work carried out by DB in determining the assessment of
vehicles negotiating DB switches.
Switch Test (6.5 and Annex F)
A test which determines the loading on the turnout branch in switches was not specified in
EN°14363:2005. However, it was mentioned in the scope that this is an open point and a future
inclusion of turnout runs in switches with R ≤ 190 m in the normal and simplified measurement method
is possible if test conditions will be fixed after further investigations.
In UIC 518:2009 test conditions have been specified in chapter 6.1.6 and Appendix N. These test
conditions are adopted and incorporated in this revision, chapter 6.5 and Annex F. It has to be
mentioned that no requirements for the assessment of the vehicle behaviour in switches and crossings
are specified in this revision of EN 14363. Annex F is informative and presents a methodology for a
consistent approach.
After an increase of rail failures in switch blades, see Figure 2, Deutsche Bahn carried out fatigue tests of
switch blades in order to determine the fatigue limit at the most critical section (fixed end of the switch
blade). With the help of Finite Element calculations the maximum permissible Y and Q forces were
determined in order to respect the fatigue stress limit.

Key
1 broken switch blade causes a high risk of derailment
Figure 2 — Broken switch blade in a switch (diamond crossing) with R = 190 m
6.7 Running safety in curved crossings for vehicles with small wheels
There is no international requirement for the assessment of the passage of a vehicle with small wheels
as defined in this revision of EN 14363. The methodology given in Annex E is derived from earlier work
carried out by
...