prEN 14363-5
(Main)Railway applications - Testing and simulation for the acceptance of running characteristics of railway vehicles operated on the heavy rail network - Part 5: Calculations/Simulations
Railway applications - Testing and simulation for the acceptance of running characteristics of railway vehicles operated on the heavy rail network - Part 5: Calculations/Simulations
This document applies to all rail vehicles including OTM’s and Road-rail machines, which are operated on the heavy rail network with standard track gauge 1 435 mm and nominal static vertical wheelset forces up to 350 kN.
This document may also be applicable (partly or in full) to:
— rail systems with different track layout, e.g. urban rail systems and/or,
— rail systems with other than 1 435 mm nominal track gauge.
Note : For such rail systems other than 1 435 mm track gauge or urban rail systems, the related post analysis, limit values and test conditions could be different. They are specified nationally taking into account track design and operating conditions.
This document contains methods to replace tests specified in EN 14363-2, EN 14363-3 and EN 14363-4, completely or partly or to support the assessment of rail vehicles according to this document.
Bahnanwendungen - Prüfungen und Simulationen für die Bewertung der fahrtechnischen Eigenschaften von Schienenfahrzeugen, die auf dem Vollbahnnetz betrieben werden - Teil 5: Berechnungen/Simulationen
Applications ferroviaires - Essais en vue de l'évaluation du comportement dynamique des véhicules ferroviaires circulant sur un réseau du système ferroviaire lourd - Partie 5 : Calculs/Simulations
Železniške naprave - Preskušanje in simulacija za oceno voznih lastnosti železniških vozil, ki obratujejo na omrežju težkih železniških prog - 5. del: Izračuni/simulacije
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
01-september-2025
Železniške naprave - Preskušanje in simulacija za oceno voznih lastnosti
železniških vozil, ki obratujejo na omrežju težkih železniških prog - 5. del:
Izračuni/simulacije
Railway applications - Testing and simulation for the acceptance of running
characteristics of railway vehicles operated on the heavy rail network - Part 5:
Calculations/Simulations
Bahnanwendungen - Prüfungen und Simulationen für die Bewertung der fahrtechnischen
Eigenschaften von Schienenfahrzeugen, die auf dem Vollbahnnetz betrieben werden -
Teil 5: Berechnungen/Simulationen
Applications ferroviaires - Essais en vue de l'évaluation du comportement dynamique
des véhicules ferroviaires circulant sur un réseau du système ferroviaire lourd - Partie 5 :
Calculs/Simulations
Ta slovenski standard je istoveten z: prEN 14363-5
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 2025
ICS Will supersede EN 14363:2016+A2:2022
English Version
Railway applications - Testing and simulation for the
acceptance of running characteristics of railway vehicles -
Part 5: Calculations/Simulations
Applications ferroviaires ¿ Essais en vue de l'évaluation Bahnanwendungen - Versuche und Simulationen für
du comportement dynamique des véhicules die Bewertung der fahrtechnischen Eigenschaften von
ferroviaires circulant sur un réseau du système Schienenfahrzeugen, die auf dem Vollbahnnetz
ferroviaire lourd ¿ Partie 5 : Calculs/Simulations betrieben werden - Teil 5:
Berechnungen/Simulationen
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, Türkiye 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
© 2025 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 14363-5:2025 E
worldwide for CEN national Members.
Contents Page
European foreword . 4
Introduction . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 Calculations and simulations for safety against derailment on twisted track . 7
4.1 Test method 1 and test method 2 . 7
4.2 Test method 3 . 7
5 Calculations and simulations for displacement characteristics . 8
6 Simulations of loading of the diverging branch of a switch . 8
7 Simulations of running safety in curved crossings for vehicles with small wheels . 8
8 Simulations of on-track tests . 8
8.1 Introduction . 8
8.2 Fields of application . 9
8.2.1 General. 9
8.2.2 Extension of the range of test conditions . 9
8.2.3 Assessment of vehicles following modification . 9
8.2.4 Assessment of new vehicles by comparison with an already approved reference
vehicle . 10
8.2.5 Investigation of dynamic behaviour in case of fault modes . 11
8.3 Validation . 11
8.3.1 General principles . 11
8.3.2 Vehicle model . 11
8.3.3 Validation of the vehicle model . 12
8.4 Input . 26
8.4.1 Introduction . 26
8.4.2 Vehicle model . 26
8.4.3 Vehicle configuration . 27
8.4.4 Track data . 27
8.4.5 Track model parameters . 28
8.4.6 Wheel/rail contact geometry . 28
8.4.7 Rail surface condition . 28
8.4.8 Direction of travel . 29
8.4.9 Speed . 29
8.4.10 Position of the vehicle in the trainset . 29
8.4.11 Frequency content of simulations . 30
8.5 Output . 30
8.5.1 Methods to determine the estimated value from the simulation . 30
8.6 Documentation . 31
Annex A (informative) Computer simulations designed to examine whether the vehicle has
an acceptable resistance to flange climbing derailment at low speed . 32
A.1 General requirement . 32
A.2 Computer output . 32
A.3 Track input . 32
A.4 Body-bogie yaw torque . 33
A.5 Performance requirement . 34
Annex B (informative) Examples for model validation according to method 1 . 35
Annex ZA (informative) Relationship between this European Standard and the Essential
Requirements of EU Directive (EU) 2016/797 aimed to be covered . 42
Bibliography . 44
European foreword
This document (prEN 14363-5:2025) 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 together with prEN 14363-1:2025, prEN 14363-2:2025, prEN 14363-3:2025, and
prEN 14363-4:2025 will supersede EN 14363:2016+A2:2022.
EN 14363:2025 includes the following significant technical changes with respect to
EN 14363:2016+A2:2022.
This document is one of the series EN 14363 Railway applications — Testing and Simulation for the
assessment of running characteristics of railway vehicles as listed below:
— Part 1: General;
— Part 2: Safety against derailment on twisted track;
— Part 3: Stationary tests that are not obligatory on European level;
— Part 4: On-track testing;
— Part 5: Simulations and calculations;
— Part 6: Background information to the EN 14363 series of standards.
This document has been prepared under a standardization request addressed to CEN by the European
Commission. The Standing Committee of the EFTA States subsequently approves these requests for its
Member States.
For the relationship with EU Legislation, see informative Annex ZA, which is an integral part of this
document.
It is not necessary to require further assessment of vehicles which have been already assessed under
the conditions of previous standards in this field. Test results achieved under the conditions of the
previous standards remain valid and can be used for the extension of field of application of a vehicle or
vehicle design according to this series of standards.
Introduction
General information for the application of this document is given in prEN 14363-1:2025.
1 Scope
This document applies to all railway vehicles including OTM’s and Road-rail machines, which are
operated on the heavy rail network with standard track gauge 1 435°mm and nominal static vertical
wheelset forces up to 350 kN.
This document may also be applicable (partly or in full) to:
— rail systems with different track layout, e.g. urban rail systems and/or;
— rail systems with other than 1 435 mm nominal track gauge and/or;
— non-public rail networks and vehicles, e.g. mine rail systems.
NOTE For rail systems other than 1 435 mm track gauge or urban rail systems, the related post analysis, limit
values and test conditions could be different. They are specified nationally taking into account track design and
operating conditions.
This document contains methods to replace tests by simulations and/or calculations specified in
prEN 14363-2:2025, prEN 14363-3:2025 and prEN 14363-4:2025, completely or partly or to support
the assessment of railway vehicles according to this document.
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.
prEN 14363-1:2025, Railway applications — Testing and Simulation for the assessment of running
characteristics of rail vehicles operated on the heavy rail network — Part 1: General
EN 13848-1:2019, Railway applications - Track - Track geometry quality - Part 1: Characterization of
track geometry
EN 13848-2:2020, Railway applications - Track - Track geometry quality - Part 2: Measuring systems -
Track recording vehicles
EN 17343:2023, Railway applications - General terms and definitions
3 Terms and definitions
For the purposes of this document, the terms and definitions given in prEN 14363-1:2025 and
EN 17343:2023 apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https://www.iso.org/obp/
— IEC Electropedia: available at https://www.electropedia.org/
At draft stage.
4 Calculations and simulations for safety against derailment on twisted track
4.1 Test method 1 and test method 2
A replacement of physical testing of safety against derailment on twisted track according to test
method 1 or test method 2 by calculations or simulations requires that a comparison of test results and
calculation or simulation results shows credible results achieved for a tested reference vehicle (see
prEN 14363-1:2025, 3.17) related to:
— vertical wheel forces and guiding forces for test method 1 testing or test method 2 testing of the
reference vehicle; or
— vertical wheel forces and yaw moment for test method 3 testing of the reference vehicle.
The calculations performed to demonstrate safety against derailment on twisted track shall be
performed either by using the process specified for test method 2 testing or by simulating running
through a twisted curve with a radius of 150 m. The friction coefficient on the inner rail running surface
shall be 90 % of t specified in prEN 14363-2:2025, 4.3, where an angle of attack of 20 mrad shall be
dry
used.
If running through a twisted curve with a radius of 150 m is chosen, the track shall have the vehicle test
twist specified for test method 1. The bogie test twist shall be applied either by shimming of the bogie
model (as when testing) or by introducing a dip in the most critical position of the track as described in
Annex A. As assessment criterion, the quotient Y/Q shall be used with the limit value specified for test
method 2. If a coefficient of friction of 0,36 is used on the outer wheel flange, then Y/Q or the wheel lift
can be used as an acceptance criterion.
NOTE 1 The assessment criterion of method 1 testing “wheel lift” is very sensitive to the friction conditions.
NOTE 2 The possible manipulation of the track when simulating test method 1, means that the simulation is
done only approximately per test method 1.
The calculated result (Y/Q) for the assessed vehicle shall remain 10 % below the limit value specified
a
for test method 2. In a deflated suspension condition the 10 % margin does not apply.
In case a simulation is performed with a model that is validated according to the validation method 1,
described in 8.3.3.3, the confidence in the results is higher than in the process described above. Then, it
is not necessary to apply the 10 %-margin to the normal vehicle status.
If during the tests of the reference vehicle a coefficient of (Y/Q) higher than 100 % of τ occurred, the
i dry
calculation method can be further used to normalize measurement results, see prEN 14363-2:2025, 4.3.
4.2 Test method 3
Computer simulation according to informative Annex A may be used to assess the performance of safety
against derailment in twisted track; this simulation is phase 2.
Phase 2 can only be used with a validated model. Typically, the results of phase 1 are used to validate
the work carried out in phase 2, where phase 1 is the test method described in prEN 14363-2:2025,
4.5.3.1; test results of a reference vehicle (see prEN 14363-1:2025, 3.17) or test results according to test
method 2 (see prEN 14363-2:2025, 4.5.2) may be used for the model validation.
5 Calculations and simulations for displacement characteristics
The determination of the displacement characteristics is carried out by simulation with a validated
model fit for purpose either for method 1 (vehicle while standing) or method 2 (on-track tests), both of
prEN 14363-3:2025, Clause 4. The validation method shall be validation method 1, see 8.3.3.3, however
adapted to the required validation range for the selected method simulated (vehicle while standing or
on-track testing).
6 Simulations of loading of the diverging branch of a switch
If a validated model per validation method 1 (see 8.3.3.3), fit for purpose exists, then it is allowed to
execute simulation for assessment of loading of the diverging branch of a switch.
7 Simulations of running safety in curved crossings for vehicles with small
wheels
The proof of running safety in a curved crossing may be performed by simulations in a full curve
without crossing using a validated model (see 8.3.3.3, validated to ΣY or H, or see 8.3.3.4). Therefore H-
forces (or ΣY-forces) and angles of attack shall be calculated for a 450 m curve without cant for a
running clearance between wheel and rail within the range 10 mm ≤ (TG - SR) ≤ 20 mm.
The friction coefficient shall be varied between 0,05 and 0,45 in steps of 0,1. The following speeds shall
be investigated: 10 km/h, 25 km/h, 40 km/h and 60 km/h.
The assessment shall be made against the criteria given in prEN 14363-3:2025, 6.4.4.
8 Simulations of on-track tests
8.1 Introduction
The dynamic performance of the vehicle shall normally be verified by tests (static tests and on-track
tests), but the use of simulation in place of on-track test is permitted under controlled conditions. The
objective when using simulation is to achieve the same level of confidence in the results as would be
achieved by on-track tests. The simulation process described in this annex sets out one means by which
this can be achieved. Other simulation procedures that achieve the same level of confidence are also
permitted.
The range of conditions of the validation determines the scope for which the model is then approved for
simulations. Therefore it is recommended that the simulation validation covers the widest practical
range of test conditions.
The limits and guidelines related to simulation and validation stated in this annex are based on the
current state of the art. This implies that the given criteria, conditions, methods, etc, are to be seen as
preliminary to gain experience and may most probably be reconsidered at the next update of the
standard.
The validation processes described in this document relate only to the simulation of on-track tests
described in prEN 14363-4:2025.
8.2 Fields of application
8.2.1 General
Four cases of application where numerical simulations can be used in place of testing are detailed in
this annex. These are:
— extension of the range of test conditions where the full test programme has not been completed;
— approval of vehicles following modification;
— approval of new vehicles by comparison with an already approved reference vehicle;
— investigation of dynamic behaviour in case of fault modes.
The scope of these cases of application and the conditions for use of numerical simulation is described
in the following subclauses. Other cases of application may exist.
A vehicle model shall be developed and validated by comparison with the available test results in
accordance with 8.3.
8.2.2 Extension of the range of test conditions
Where on-track tests according to this document have been carried out, but the full range of test
conditions has not been satisfied, then it is permissible to use numerical simulations to cover the
deficiencies as part of the vehicle approval. This situation could arise where:
— sufficient track length is not available to meet the requirements for some test zones;
— the full range of speed and cant deficiency has not been tested;
— the full range of wheel/rail contact conditions has not been covered;
— measuring channels failed, or provided unreliable results.
It is permitted to use numerical simulations for a single or multiple test zones where the test results are
not complete, if the variance of the errors of measured sections is similar to those of the simulated
sections. A sufficient number of track sections from each of simulations and measurements is necessary
to compare the statistics.
NOTE This method assumes that measurements and simulation belong to similar basic populations. Checking
that the heterogeneity is not reduced or constant variance is not significantly altered can partly prove this.
8.2.3 Assessment of vehicles following modification
Vehicle modifications may be carried out for a number of different reasons, for example:
— change of the use of the vehicle;
— upgrade of the vehicle;
— modifications to improve the running behaviour:
— during or following the approval test programme;
— when some tests were done in a preliminary vehicle configuration and the final configuration is
defined afterwards.
A model of the original vehicle is developed and validated against the test results for that vehicle in
accordance with 8.3. The model of the vehicle is then modified to represent the physical changes to the
vehicle as a result of the modification. Only the changes that influence the dynamic behaviour are
required to be included in the modified model. The revised model is used to simulate the dynamic
behaviour and the results are compared with the limit values for assessment.
Simulations for all test zones shall be carried out to demonstrate that the vehicle performance of the
new vehicle is consistent when compared to the previously tested vehicle. The influence that the
changed parameter(s) has (have) on the dynamic performance shall be examined for all zones. The
results of this examination shall be reported and the influence on the performance indicated.
If a vehicle has been tested according to prEN 14363-2:2025, prEN 14363-3:2025 or
prEN 14363-4:2025 and found to exceed some of the limit values, then it is permitted to use numerical
simulations to demonstrate that modifications to the vehicle will improve the behaviour sufficiently to
meet the limits. The values that previously exceeded the limits shall be under the limit values for track
loading and at least 10 % below the limits for running safety. At the same time all other values shall
remain below the limit and not increase by more than 1/3 of the previous margin to the limit value. In
this situation the vehicle can be regarded as acceptable for the previously deficient limit values.
In any of the above cases it shall be independently confirmed (see 8.3.3.6), that the modifications have
been correctly and appropriately applied to the model so that the resulting vehicle response is credible
in the context of the original model and achieves the required effect on vehicle behaviour. This shall be
documented in the reviewer's report.
NOTE In some cases, it can be useful to check if the modifications are applied correctly by reference to limited
test results.
The data from the simulation is to be used to assess the modified vehicle.
8.2.4 Assessment of new vehicles by comparison with an already approved reference vehicle
Where vehicles are being introduced with a range of different types within the fleet (e.g. multiple units,
etc.) then one vehicle type is defined as the reference vehicle. Vehicles that are similar to the reference
vehicle can then be approved using numerical simulations, rather than on-track tests, to demonstrate
the behaviour of the new vehicles, subject to the conditions given below.
Model(s) of the new vehicle(s) that are to be assessed are to be developed from the reference vehicle.
The existing and changed parameters are to be included in the simulation to demonstrate the influence
of the changes on the performance.
Simulations for all test zones are carried out to demonstrate that the vehicle performance of the new
vehicle is consistent when compared to the reference vehicle. The influence that the changed
parameter(s) has (have) on the dynamic performance is to be examined for all test zones. The results of
this examination are to be reported and the influence on the performance indicated.
If the change to the dynamic performance results in:
— an increase in any assessment quantity compared to the reference vehicle;
— and/or a fundamental change in the frequency and/or amplitudes of the dynamic response;
then a full review shall be carried out.
This review shall include analysis that investigates the changes to the dynamic response(s) of the new
vehicle compared to the reference vehicle and an associated explanation of the effects identified. This
comparison shall be carried out for at least 3 sections of each test zone, if it demonstrates that:
— the assessment quantities for running safety (see prEN 14363-4:2025, 4.5.2) from simulations do
not increase by more than 1/3 of the previous margin to the limit values;
— and at the same time the values for track loading (see prEN 14363-4:2025, 4.5.3) from simulations
do not increase by more than 2/3 of the previous margin to the limit values;
then the simulation can be used for vehicle assessment.
NOTE 1 Changes to individual components such as springs or dampers are likely to be acceptable provided the
characteristics of the changed components are known and the changes are not extreme. Limited changes to
masses, inertias or centres of gravity are also likely to be acceptable. A change to the concept of the suspension or
introduction of components which were not present in the validated model for the tested vehicle is less likely to
be acceptable.
Confirmation that the modifications have been correctly and appropriately applied to the model so that
the resulting vehicle response is credible in the context of the original model shall be independently
reviewed and documented in the reviewer's report (8.3.3.6).
NOTE 2 In some cases it could be useful to check if the modifications are applied correctly by reference to
limited test results.
8.2.5 Investigation of dynamic behaviour in case of fault modes
The use of simulation to investigate fault modes in support of the requirements of prEN 14363-1:2025,
5.2.2 is permitted. In such cases the validity of the simulation of fault modes shall be independently
reviewed and confirmed as being appropriate and the outcome of the review shall be documented in
the reviewer's report. The process of selecting and assessing fault modes is independent from the
assessment method (test method or simulations).
The model shall only be used within its range of validity.
8.3 Validation
8.3.1 General principles
Models used in numerical simulations are required to be validated by comparison with test results from
the vehicle that is being modelled.
Information that is required to carry out the validation should include:
— design data for the modelled vehicle that is sufficiently detailed to enable the features that influence
the vehicle dynamics to be incorporated into the model;
— test results for the modelled vehicle in a form that can be used for model validation including time
history data in a digital form. It is necessary that these tests and data include a representative range
of track conditions, curves, cant deficiency, speed and wheel/rail contact conditions;
— track data from the original test route to enable validation to be undertaken.
In case not all the information required in this annex can be used (e.g. because it is not available and
cannot be obtained) in the validation of the model, the impact of the missing data on the model accuracy
shall be assessed. As a consequence of this assessment, limitations on the application range of the
model may need to be defined. This will need to be independently reviewed.
8.3.2 Vehicle model
The model shall include the main components such as wheelsets, bogies/running gear, vehicle body and
all of the relevant connections between them (e.g. geometry, linear/nonlinear stiffness, damping,
clearances, etc.). Data describing the vehicle body shall be included to the level of detail required to
represent dynamic effects that are prominent in the dynamic performance (e.g. masses, inertias,
position of centre of gravity, significant eigenmodes/flexible bodies).
The precision and level of detail that is appropriate in a model will depend on the particular assessment
quantities that are to be evaluated.
Sufficient detail and precision is required to give confidence in the predicted vehicle performance under
consideration.
8.3.3 Validation of the vehicle model
8.3.3.1 Introduction
In order to generate valid results, it is necessary that numerical simulations are carried out with care to
ensure that:
— the vehicle model is a good representation of the actual vehicle;
— the software used is appropriate for the application;
— the correct conditions have been covered;
— the engineers undertaking the simulations are competent;
— and therefore, the simulation results will be valid.
If numerical simulations are to be used for a vehicle in different conditions (for example tare, laden,
inflated, deflated, etc.), separate models will need to be validated for each condition.
Two validation methods are described here; these are detailed in 8.3.3.3 and 8.3.3.4. Both are regarded
as equally valid and when validation is carried out only one of the methods is required to be used. The
technique that is given for each method only applies to that method.
8.3.3.2 Validation process, general
The validation process is based on comparisons between physical test results of the vehicle and
numerical simulations of the same tests. The primary purpose of validating a numerical vehicle model is
to use that model to simulate the vehicle behaviour in-lieu of actual on-track tests. Vehicle approval
requires the assessment of the vehicle's static, quasi-static and dynamic behaviour. Therefore, it is
helpful if the model includes validation against the static, quasi-static and the dynamic tests.
The range of conditions, see e.g. 8.3.3.3.3.1, of the dynamic validation then determines what the model
is approved to be used for. Therefore, it is recommended that the validation tests and simulation
comparisons cover the widest practical range of conditions.
The validation process should also be made across the appropriate dynamic frequency range. All
comparisons between simulation and actual on-track test results shall be made using the same vehicle
model and software. A model that has been validated shall not be changed for subsequent simulations,
except for the conditions given in 8.2.3 and 8.2.4.
It is required that the results of all appropriate work carried out to validate the vehicle model are
presented in a validation report.
The following clauses describe the process to be used to ensure that the model is a good representation
of the actual vehicle and it is suitable to be used for vehicle approval.
The data that can be required in order to undertake validation of the numerical simulations are given in
Table 1.
The processes of model validation according to validation method 1 and validation method 2 are
illustrated in the following flowchart (Table 1). Details about the two methods are given in 8.3.3.3 and
8.3.3.4.
It may also be helpful for the validation process to include additional measurement quantities. It is
strongly recommended to measure the primary and secondary vertical suspension displacements as
well as the secondary lateral displacement. It may also be helpful to measure the primary longitudinal
and lateral suspension displacements. In addition, the length of yaw dampers and inter-car dampers can
be of interest.
Figure 1 — Model validation methods
8.3.3.3 Validation process according to method 1
8.3.3.3.1 General
The validation process of method 1 is based on the analysis of the vehicle model with respect to the
vehicle response to various inputs. The results of this analysis are judged by an independent reviewer.
The comparison of simulation and test results can include the following parameters:
— assessment quantities according to this document (percentiles as evaluated per track section as
well as standard deviation and estimated maximum for the test zone) as appropriate – see
prEN 14363-4:2025, Annex H;
— key frequencies of the following measurement quantities over a sample of track sections:
— vehicle body lateral and vertical accelerations at each end;
— vehicle body bounce and pitch accelerations (derived from in and out of phase values of body
end vertical accelerations);
— calculated vehicle body lateral and yaw accelerations (derived from in and out of phase values
of body end lateral accelerations);
— bogie lateral and yaw accelerations;
— bogie vertical and pitch accelerations (if available);
— ΣY forces (key frequencies);
— distribution plots of values for Y and Q forces as function of curve radius, cant deficiency, etc. (as
appropriate). See one example for Q in Figure 12;
— sample time histories over straight and curved track sections for all the measurement quantities.
Table 1 contains suggested parameters to be considered in the validation process.
A comparison of vertical wheel force on each individual wheel is also reasonable. The deviations should
be as low as possible. However, it should be recognized that the measurements of vertical wheel force
will vary between successive measurements of the same vehicle, particularly for vehicles with friction
damping like freight wagons. For such vehicles, maximum deviation up to 15 % could be acceptable.
Examples of good and less good model validations are given in informative Annex B.
Table 1 — Parameters for model validation
Maximum deviation
Application for a
between simulation
successful validation
and measurement
Average
Parameter Remark
deviation
Maximum of all Recommended
b
Required
deviation wheelsets (informative)
, bogies,
etc.
Static wheelset force P 6 % 3 % X Based on 0
F0
Static bogie force Q 3 % 3 % X Based on 0
B0
Static side force Q 3 % 3 % X Based on 0
S0
Wheel force in twist Q 15 % 7 % X Based on 0
t
Wheel unloading in ΔQ 10 % X
t
twist
displacement not not X
characteristics specified specified
a
Lateral forces in Ya, Yi MAX(8 %; not X
150 m curve (or in a 3 kN) specified
similar tight curve)
a
Bogie rotational X- not not X
resistance Factor specified specified
Flexibility coefficient s not not X Based on
(and spring specified specified measurement
deflections) of flexibility
c
coefficient
Eigenfrequencies of f not not X Identified e.g.
the rigid body specified specified by wedge tests
movements of vehicle
body
Quasi-static lateral Y MAX(10 % not X Measured on
qst
forces ; 4 kN) specified on-track tests;
Check of all
measured
wheels
required
Quasi-static wheel Q 8 % not X Measured on
qst
force specified on-track tests;
Check of all
measured
wheels
c
required
Lateral forces Y Assessmen not X
t of the specified
time
histories
and FFT
results
Vertical wheel force Q Assessmen not X
t of the specified
time
histories
and FFT
results
.. ..
Vehicle body Assessmen not X
y , z
accelerations t of the specified
time
histories
and FFT
results
.. ..
Bogie accelerations Assessmen not X
y , z
t of the specified
time
histories
and FFT
results
a
At least one or the other.
b
In case any of the required parameters is not evaluated, the application of the model should be limited accordingly.
c
The maximum allowed deviation for Q may be useful when defining maximum allowed deviations also for the
qst
flexibility coefficient.
8.3.3.3.2 Validation using static tests or slow speed tests
8.3.3.3.2.1 Objective
As part of the model’s validation process, it is expected to use results from static or slow speed tests.
The results of existing static and slow speed tests can be used, special tests are not required.
Depending on the analysis undertaken, these results are used to validate different aspects of the vehicle
model, namely:
— vertical wheel forces and force distribution;
— behaviour on twisted track;
— bogie rotation;
— flexibility coefficient;
— other static test results.
8.3.3.3.2.2 Vertical wheel forces and force distribution
For vertical wheel forces and force distributions it is necessary that the following values are calculated
and compared with the test results:
— vertical wheel force on each individual wheel;
— vertical wheel forces on each wheelset (sum of two wheels);
— vertical wheel forces on each bogie (sum of wheels);
— vertical wheel forces on each side of the vehicle (sum of wheels on that side).
It is required that the results of the comparison are reported including differences as a percentage of
the appropriate test result.
Table 1 presents the maximum differences between simulation and test results that are acceptable for a
well validated model.
8.3.3.3.2.3 Behaviour on twisted track
Where tests are undertaken to determine the behaviour on twisted track it is recommended that the
appropriate measurement quantities are calculated and compared with the test results. This will
normally include (dependent on the measuring method):
— vertical wheel forces during the testing;
— suspension displacement during the testing;
— plots of vertical wheel forces against applied twist;
— hysteresis;
— magnitude of any wheel lift.
The maximum deviation for wheel unloading is also given in Table 1.
8.3.3.3.2.4 Bogie rotation
Where bogie rotation tests are undertaken it is recommended that the appropriate measurement
quantities are calculated and compared with the test results. This can include:
— bogie rotation angle;
— applied force/torque;
— plots of applied force/torque against rotation angle;
— different rotational speeds.
8.3.3.3.2.5 Displacement characteristics
Where static tests to determine the displacement characteristics are undertaken, it is recommended
that the appropriate measurement quantities are calculated and compared with the test results. This
can include:
— vehicle body roll angle;
— bogie roll angle;
— lateral displacement of specific positions on body/bogie;
— vertical displacement of specific positions on body/bogie.
8.3.3.3.2.6 Other static tests
Additional test not defined in prEN 14363-2:2025 and prEN 14363-3:2025 of this document may
include:
— force/deflection measurements of components;
— force/deflection measurements of the suspension when mounted in the vehicle;
— etc.
The results of these tests can also be used to validate the simulation model. Therefore the results shall
be compared with the simulation results obtained under the same boundary conditions in an
appropriate way.
NOTE Such tests can be performed for example in lateral and longitudinal directions. Examples are tests
where the vehicle body is moved in lateral direction relative to the running gear or where the wheelset is moved
in longitudinal direction relative to running gear frame. In many cases it is useful to test different values of
amplitude and frequency in order to investigate hysteresis and damping.
8.3.3.3.3 Validation using dynamic tests
8.3.3.3.3.1 Range of validation
It is necessary to consider the parameters given below in determining the range of applicability of the
validated model. The vehicle model is to be considered as validated for the range of conditions covered
in the comparisons, presuming that satisfactory results are obtained.
The following parameters shall be considered and the range of conditions covered shall be reported in
the validation report:
— track geometric irregularities – shall be sufficient to excite the vehicle suspension in all directions
and shall include track with irregularity at both ends of the quality range;
— vehicle speed – validation is limited to the speed range tested;
— vehicle cant deficiency – validation is limited to the cant deficiency range tested;
— straight track – sufficient length and conditions, such as gauge and contact as well as friction
conditions, to demonstrate vehicle stability are required;
— curve track sections – shall include maximum cant deficiency;
— very small radius curves – shall be included to assess behaviour in these conditions;
— wheel rail contact co
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