CEN/TR 15273-5:2025

SLOVENSKI STANDARD
01-marec-2026
Železniške naprave - Profili - 5. del: Ozadje, razlaga in praktični primeri
Railway applications - Gauges - Part 5: Background, explanation and worked examples
Bahnanwendungen - Begrenzungslinien - Teil 5: Hintergrund, Erläuterung und
praktizierte Beispiele
Applications ferroviaires - Gabarits - Partie 5 : Contexte, explication et exemples
Ta slovenski standard je istoveten z: CEN/TR 15273-5:2025
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 15273-5
TECHNICAL REPORT
RAPPORT TECHNIQUE
October 2025
TECHNISCHER REPORT
ICS 45.020; 45.060.01
English Version
Railway applications - Gauges - Part 5: Background,
explanation and worked examples
Applications ferroviaires - Gabarits - Partie 5 : Bahnanwendungen - Begrenzungslinien - Teil 5:
Contexte, explication et exemples Hintergrund, Erläuterung und praktizierte Beispiele

This Technical Report was approved by CEN on 18 August 2025. 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, 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.
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. CEN/TR 15273-5:2025 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 Symbols and abbreviations . 6
5 General. 6
6 Historical background . 7
6.1 Why gauging?. 7
6.2 Defined gauges . 8
6.3 Absolute and comparative process . 9
7 Technical background . 10
7.1 Defined gauges . 10
7.1.1 Rolling stock . 10
7.1.2 Infrastructure . 59
7.1.3 Creating a defined gauge . 72
7.2 Absolute and comparative process . 76
7.2.1 Main steps to performing an absolute gauging assessment . 76
7.2.2 Main steps to performing a comparative gauging assessment . 77
7.2.3 Clearances and control measures . 77
7.2.4 Effective position of the track . 78
7.2.5 Platform stepping distances . 79
7.2.6 Generation of track data for use in absolute and comparative process . 82
7.2.7 Background to statistical evaluation and clearance categories in EN 15273-1:2025 89
7.2.8 Information on vehicle “datum” used in the calculation of swept envelopes . 89
7.2.9 Guidance on choosing between two or three datum points for calculation of maximum
suspension displacement . 90
7.2.10 Determining survey and measurement accuracy . 90
8 Examples: defined kinematic gauges . 91
8.1 Rolling stock . 91
8.1.1 General. 91
8.1.2 Passenger coach with 2 trailer bogies without rotational bump stops with gauges G1
+ GI2 . 91
8.1.3 Passenger coach with 2 trailer bogies with curve dependent bump stops with G1 + GI2
................................................................................................................................................................... 97
8.1.4 Multiple unit with 1 trailer bogie + 1 motor bogie with GB + GI2 . 100
8.1.5 Application for articulated trainset . 106
8.1.6 Checking the pantograph in the collecting position . 111
8.1.7 Analysis of an open door and steps for FR 3.3 and GI2 . 113
8.1.8 Calculation of bogie gauge for G1+GI2 . 117
8.1.9 Tilting trains with an active system . 122
8.1.10 Passive tilting articulated vehicles with independent wheels . 129
8.1.11 Wagon and marshalling hump . 137
8.1.12 Defined new formulae in special cases . 141
8.2 Infrastructure . 146
8.2.1 General . 146
8.2.2 Gauge GB + GI2 on straight track . 146
8.2.3 Gauge GB + GI2 on curved track . 156
8.2.4 Pantograph. 165
8.2.5 Platform calculation . 169
8.2.6 Distance between the track centres . 171
8.2.7 Transition curve . 175
9 Examples: defined dynamic gauges . 180
9.1 Rolling stock . 180
9.1.1 Multiple unit . 180
9.1.2 Pantograph. 188
9.2 Infrastructure . 190
9.2.1 General . 190
9.2.2 Gauge SEa on straight track . 190
9.2.3 Gauge SEa on curved track . 196
9.2.4 Pantograph for SEa . 204
9.2.5 Platform calculation for SEa . 205
9.2.6 Distance between track centres for SEa . 206
10 Examples: absolute and comparative gauging process . 209
10.1 Absolute example . 209
10.1.1 Introduction . 209
10.1.2 Input . 209
10.1.3 Methodology . 213
10.1.4 Calculating the swept envelope . 216
10.1.5 Building the swept envelope . 216
10.1.6 Including the effective track position . 217
10.1.7 Calculating the clearance . 218
10.2 Comparative example . 219
10.2.1 Input data . 219
10.2.2 Methodology . 219
10.2.3 Results . 221
10.3 Hybrid example – combination of comparative and absolute method . 221
10.4 Absolute gauging example for pantographs . 223
10.4.1 Introduction . 223
10.4.2 Method 1 – static pantograph gauge example . 223
10.4.3 Method 2 – Benchmark sway values example . 225
Bibliography . 227

European foreword
This document (CEN/TR 15276-5:2025) 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.
The EN 15273 series, Railway applications — Gauges, consists of the following parts:
 EN 15273-1:2025, General — Common rules for rolling stock and infrastructure, which gives the
general explanations of gauging and defines the sharing of the space between rolling stock and
infrastructure;
 EN 15273-2:2025, Rolling stock, which gives the rules for dimensioning vehicles;
 EN 15273-3:2025, Infrastructure, which gives the rules for positioning the infrastructure;
 EN 15273-4:2025, Catalogue of defined gauges, which includes a non-exhaustive list of reference
profiles and parameters to be used by infrastructure and rolling stock; and
 CEN/TR 15273-5:2025, Background, explanation and worked examples (this document).
Any feedback and questions on this document should be directed to the users’ national standards body.
A complete listing of these bodies can be found on the CEN website.
Introduction
The aim of this document is to define the rules for the calculation and verification of the dimensions of
rolling stock and infrastructure from a gauging perspective.
This document gives gauging processes taking into account the relative movements between rolling stock
and infrastructure and the necessary margins or clearances.
This part of the series EN 15273 is intended to be used in conjunction with the following parts:
 Part 1: General — Common rules for rolling stock and infrastructure;
 Part 2: Rolling stock;
 Part 3: Infrastructure;
 Part 4: Catalogue of defined gauges.
1 Scope
This document presents the background of some gauging methods, gives calculation examples for both
rolling stock and infrastructure based on gauging methods from EN 15273-2:2025 and EN 15273-3:2025,
and also demonstrates some relevant formulae.
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 15273-1:2025, Railway applications — Gauges — Part 1: General common rules for rolling stock and
infrastructure
3 Terms and definitions
For the purposes of this document, the terms and definitions given in EN 15273-1:2025 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
4 Symbols and abbreviations
For the purposes of this document, the symbols and abbreviations given in EN 15273-1:2025 apply.
5 General
This document has been prepared by Technical Committee CEN/TC 256 “Railway applications” for better
reading and understanding of EN 15273. All examples contained in this document are for guidance and
are not contractual.
This document aims at providing background information and examples to complement the EN 15273
series. This includes infrastructure implementation, the tracks implementation and the sections for
rolling stock in order to ensure the service safety. These rolling stock are designed according to the
different types of existing or future configuration.
This document explains the general philosophy of the methods used and of the history of the evolution
of the rules. Therefore, the reader is able to adapt the philosophy or formulae to their specific cases.
6 Historical background
6.1 Why gauging?
The following photographs demonstrate the importance of gauging.
Figure 1 shows where the top corner of a container has come into contact with the bridge creating a score
through the underside of the arch. Clearance assessments undertaken correctly would have identified
this container and wagon combination to be incompatible for operation on this route. In worse
conditions, the railway vehicle coming into contact with the infrastructure could cause more damage to
both sides of the interface, or possibly derailment.

Figure 1 — Container contact on the bridge
Figure 2 shows the underside of a footstep of a passenger vehicle coming into contact with the
platform. Whilst this scenario could be considered ideal for stepping purposes at the platform-
train interface, sustained contact in this situation will result in damage to both sides of the
interface.
Figure 2 — Clearance between access door steps and platform
6.2 Defined gauges
The historical development of the rules of kinematic gauging is the subject of UIC 505-5. In summary, the
needs of transport and of interoperability led railways operators in Continental Europe to adopt a
common gauge in 1913.
This gauge was defined as the UT (Technical Unit) and was a static gauge.
Until then, the rules used by the networks were not unified and posed interoperability problems. The UT
static gauge consists of a reference profile and associated rules, which allows the Infrastructure Manager
to position infrastructure, and the Railway Undertaking to design vehicles which can safely pass through
the infrastructure and pass other trains on adjacent lines.
Given the evolution of rolling stock, the lengthening of vehicle wheelbases and bogies, the increase of the
speeds and passenger comfort, etc., many parameters have therefore had an impact on the increased
flexibility of suspensions as well as the clearance between carbodies and bogies. As a result, UIC was
requested in 1953 to develop a kinematic gauge. A first version of UIC 505 was thus published in 1956,
being completed in 1957 by a table defining the lateral projections.
The basic principle of the method used at the time was the use of a reference profile to allow the clear
separation of responsibilities between the Railway Undertaking and the Infrastructure Manager, dividing
the lateral movements so that they are taken into account just once.
This breakdown led to standard values, such as for cant that is shared between the Railway Undertaking
and Infrastructure Manager. In this case, the first 50 mm of cant or cant deficiency is covered by the
rolling stock. The rest of the cant or the cant deficiency is taken into account by the infrastructure.
The same goes for the flexibility coefficient, (e.g. for the G1 gauge its value is 0,4), except that its reference
value in this case is limited by the infrastructure. If this value is exceeded by the designers of the rolling
stock, it is their responsibility to adapt the vehicles' exterior dimensions to respect the space allowed by
the infrastructure.
Thus, all parts of UIC 505 were developed for various type of rolling stock and for infrastructure.
th th
In 1991, the 5 and 7 UIC Commissions decided to group the first three leaflets under the name
UIC 505-1 and maintain UIC 505-4 and UIC 505-5.
Subsequently, the implementation of European Standards development led to the revising of these
calculation methods whilst:
 optimizing, for example using generic formulae in the calculation of the lateral reductions;
 adapting;
 because they were such striking passage reduction formulae on marshalling humps for special
wagons;
 creating rules for the area of the wheels and live parts on the roof.
Rolling stock sized according to UIC 505-1 and UIC 506 is compatible with the requirements of EN 15273
for kinematic gauges below:
 G1, GI1, GI2 and G2 for UIC 505-1;
 GA, GB, GB1, GB2, GC and GI3 for UIC 506.
6.3 Absolute and comparative process
The historical development of the absolute and comparative gauging process originated in the rail
network of Great Britain (GB). Early trains and infrastructure built were small; it was only once their
popularity was established that larger rolling stock was produced. Fortunately, the difference in size
between structures built and the limiting structure gauge meant that larger trains could be easily
accommodated. Today's railway is very different in GB; a requirement for larger, high-capacity trains,
containerised freight (in 9'6" high boxes) presents quite a different problem to small goods wagons. The
combination of cross-sectional area, shape, length and speed all place a space requirement on today's
railway that could not be dreamed about in Victorian times, although GB continues to use much of the
same infrastructure. Historically, not only were many structures built bigger than required, but the space
allowed between trains and structures was large also. This space is known as clearance. Clearance is
provided to accommodate movement of the train as it travels and to provide a safety margin to
accommodate track maintenance, unknown situations, tolerances, etc. and sometimes to provide safe
walking routes.
As GB has built progressively larger trains, they have reduced the clearance originally provided. Tracks
have been moved to accommodate the often conflicting demands of wide passenger trains and tall freight
container trains (which do not fit neatly through arched bridges and tunnels).
The simplest form originally used by GB was using static gauges. Following nationalisation, standard
gauges for locomotives (L1), carriages (C1) and wagons (W1 to W5) were introduced in 1950, these being
gauges that would fit virtually anywhere on the national railway network. The W6 gauge, larger than W5
and quickly replaced with W6a once issues regarding clearances to third rail electrified track were
identified, was added later. The W6a gauge is now the most widely used wagon gauge on the modern GB
railway network. W6a however does not guarantee route compatibility with the entire British railway
network (‘go-anywhere’), and assumes wagon type suspension parameters which makes it unsuitable for
use in building other types of rolling stock such as passenger vehicles. Whilst GB retains the use of static
gauges in some circumstances, their use has been superseded by more sophisticated analysis to make
better use of space.
Following extensive research in the 1970-80s, a methodology was established by British Rail Mechanical
and Electrical Engineering Department for the calculation of vehicle sways and drops named Design
Guide 501 or “BASS 501”. This hand-calculated technique enabled the calculation of simple vehicle body
sways from speed and cant deficiency or excess from which the dynamic space required could be
calculated and compared to structures along a route.
Since then, increasingly sophisticated computer modelling systems were developed, together with more
accurate tools for measuring the actual size of infrastructure. The systems and processes were adopted
by the GB Rail Industry as the absolute and comparative process which allowed the understanding of how
much trains move and how much safety margin to provide, to make more effective use of the existing
Victorian built infrastructure.
It is through the use of these systems and processes and that tilting trains, large containerised freight
trains and modern commuter rolling stock can be run in GB – this would not have been possible using
traditional processes without vast expenditure in providing additional (and arguably unnecessary) space
to accommodate them. Avoiding these large capital expenditures is traded off against a need to tightly
control infrastructure position and maintain a high level of asset knowledge.
The absolute and comparative gauging process cover a series of techniques that ensure that sufficient
space exists around a moving train (clearance) to provide safe operation. The complex, computer
modelling processes used in the absolute dynamic gauging process provide the greatest level of 'fit'
between trains and structures (and passing other trains).
Comparative gauging provides for the certification of compatibility by a process of demonstrating that
new rolling stock can be operated in 'the shadow' of rolling stock which already has certification on the
routes that new rolling stock will be operated on. In absolute gauging, the actual space required to run a
vehicle along a route is compared with the actual size of structures and the position of adjacent tracks
along that route.
In practice, both can only be done through computer simulation, where the dynamic swept envelopes of
candidate and comparator vehicles are compared over the range of speeds and cant deficiencies /
excesses that would be experienced on the route, where the route data is kept up to date by the
Infrastructure Manager.
7 Technical background
7.1 Defined gauges
7.1.1 Rolling stock
7.1.1.1 How to calculate the maximum construction gauge using the kinematic method
Before beginning a gauge calculation, it is necessary to agree a reference profile and associated rules (see
EN 15273-4:2025) as well as product-related data:
 the vehicle data: type of configuration, conventional or non- conventional (see 7.1.1.3), the pivot
centre distance “a”, the length of the carbody, variation of lateral clearance between the carbody and
bogies “𝑤𝑤”, depending on the curve radius;
 characteristics of bogies (motor or trailing bogie) and their suspensions (flexibility coefficient "𝑠𝑠",
downward displacements "𝐴𝐴𝐴𝐴𝐴𝐴", the semi-width between suspension springs “𝑏𝑏 ” or “𝑏𝑏 ”) wheelbase
1 2
axle "𝑝𝑝", wheel wear "𝑈𝑈𝑠𝑠𝑈𝑈" and "𝑑𝑑";
 data on conditions of operation and maintenance.
EN 15273-1:2025, 5.2 gives further explanations and links between the different parts of this standard
series.
7.1.1.2 Main steps to perform a gauge calculation
The generic procedure can be summarized as:
 know and assimilate standard(s) to respect any pertinent requirements;
 know and understand the rolling stock configuration;
 determine the relative position of the bump stops between the carbody and the bogies, check the
interference-free movement of the bogies with the carbody in very small radius curves;
 determine clearances "𝑤𝑤", as a function of the radius of the curve in the cross-section of the bogie
pivot;
 determine the lateral reductions;
 determine the vertical reductions depending on the suspension characteristics and connections;
 determine the maximum construction gauge in the relevant cross-section;
 complete this calculation by taking into account the particular components: installation of the
pantographs, sensor location, antenna, reducing gaps in access steps, etc.;
 present all results in a calculation file in order to obtain acceptance/approval;
 the calculated values can change according to the updating of the project: in this case, a new
calculation is performed.
7.1.1.3 Train configuration
When developing new configurations such as an articulated vehicle with an offset articulation or other
solution, it is necessary to apply the philosophy stated in the standard to carry out accurate calculations,
equivalent to those used elsewhere in the process.
The aim of the calculations is to search, for a given configuration, the maximum size for vehicles, thereby
improving passenger comfort and to increase freight vehicle capacity.
To take into account all criteria and the train architecture, it is necessary to design vehicles that make up
the train according to the gauge rules. Caution is necessary to adapt the formulae of this standard
according to the chosen configuration as the current edition of this standard only considers the two
bogies on conventional vehicles and articulated vehicles (see EN 15273-2:2025, A.1.3) for example for
tilting trains and for vehicles installation and track maintenance.
Figure 3 and Figure 4 show different classical configurations.

Figure 3 — Example of conventional vehicles with 2 bogies
Figure 4 — Example of articulated trainset with standard and Jakobs bogies
Figure 5 and Figure 6 show different hybrid configurations for which it is preferred to adapt the formulae.

Key
1 key vehicle
2 bogie pivot
3 articulation between carbodies
Figure 5 — Example of configuration with offset articulation

Key
1 key vehicle
2 bogie pivot
3 articulation between carbodies
Figure 6 — Example of configuration with suspended carbody
An example of development of formulae is proposed in 8.2.12 of this document for the same conditions
as conventional vehicles: straight line and constant radius.
It is necessary to check these configurations for other conditions such as reverse curves, switches and
crossings in order to be sure that these vehicles do not infringe the infrastructure gauge. Two specific
cases are checked:
— reverse curve of 190 m radius without an intermediate straight section;
— reverse curve of 150 m radius with an intermediate straight section of 6 m.
Figure 7 shows the difference in the geometric overthrow with respect a conventional vehicle when
considering train configuration corresponding to Figure 5 in a reverse curve without intermediate
straight track.
Key
1 additional geometric overthrow
2 reverse curve without an intermediate straight section corresponding to the case n°1
3 conventional vehicle centreline
4 direction of the additional lateral displacements of the carbody
Figure 7 — Example of configuration with offset articulation in a reverse curve
7.1.1.4 Running gear
7.1.1.4.1 General
The bogies and suspension systems support loads and distribute them generally on two axles, filter track
defects and improve the comfort in vehicles, including sometimes with active or passive tilting devices.
The gauging calculation of the bogie is similar to that of a vehicle on two axles but is only applicable in
the lower parts of the reference profile (see EN 15273-4:2025).
Components linking the carbody and the bogie respect the gauge. Their worst positions are analysed case
by case taking into account displacements of bogie and carbody (for example dampers, cables, deflated
pneumatic suspension, etc.).
7.1.1.4.2 Type of bogies
Two types of bogies, motor bogies and trailer bogies, have the main function of supporting the suspended
masses, to ensure the guidance on the track, and for our purpose to maintain the carbody within the limits
set by the rules of the gauging process.
For that, some bump stops limit the lateral displacements between carbody and bogies (see Figure 8 and
Figure 9 to Figure 14). The suspension systems limit the carbody rolling (via the flexibility coefficient)
and the vertical displacements by filtering the track defects.
Key
1 bump stop by the bogie pivot
2 curve dependent bump stops
3 roll bar
Figure 8 — Example of position of the lateral bumps stops and the roll bar on a trailer bogie
(See EN 15273-2:2025, Figure D.1.)
7.1.1.4.3 Flexibility coefficient and height of roll centre
See a calculation example in UIC leaflet 505-5:2010, 10.4.
7.1.1.4.4 Behaviour of the bogie on the track
The behaviour of the bogie is dependent on the adhesion between the wheel and the rail.
For the purposes of this standard, the bogies are classified according to their adhesion factor 𝜇𝜇 on starting.
If 𝜇𝜇≥ 0,19 the bogie is designated “motor”.
If 𝜇𝜇 < 0,19 the bogie is considered “trailer”.
Historical note:
Previously the formula for calculating the value of this coefficient was expressed for a stationary vehicle
in a curve with a cant (D) 0,100 m and calculated as follows:
2 2
𝐹𝐹𝑤𝑤 𝐷𝐷
�
𝜇𝜇 = � � +� �
𝑔𝑔.𝑀𝑀 𝐿𝐿
𝑒𝑒
2 ²
𝐷𝐷 0,1
Very often this formula has been written with � � = 0,0044444 …  (= � � ) and used with this
𝐿𝐿 1,5
numerical value for all European networks for all distances of L between the top of rails.
To avoid confusion, and mainly for vehicles equipped with bogies having the possibility to change their
distance between wheels, this standard uses a simplified formula leading to the same result:
Fw
𝜇𝜇 = with a limit value = 0,19
g.M
e
�( 0,19² + 0,0044444 … ) = 0,20 as in the previous version of the standard.
In the new calculation of this ratio, the effects of cant are negligible, and thus:
𝐹𝐹𝑤𝑤
𝜇𝜇 =
𝑔𝑔.𝑀𝑀
𝑒𝑒
The resulting positions of the bogies in the track are given in EN 15273-2:2025, (see coefficient 𝐴𝐴 in
EN 15273-2:2025).
7.1.1.4.5 Specific bogies calculation and particular elements
The gauge calculation involves specific calculations and checking in accordance with technologies used
for example:
 dampers; anti-yaw dampers;
 with or without anti-roll bars;
 sanding systems;
 the lubrication systems;
 grounding of braids (current return);
 tilting bogie;
 electrical and pneumatic flexible connections between carbody and bogie.
7.1.1.5 Lateral clearance between carbody and bogies
7.1.1.5.1 General
The lateral clearance 𝑤𝑤 is limited by lateral bump stops which are located between carbody and the
bogies.
Depending on the bump stop design, "𝑤𝑤" sometimes has a fixed value or a value variable with curve
radius.
For the purposes of this document, these values are transposed at the bogie pivot.
7.1.1.5.2 The bump stops
7.1.1.5.2.1 Bump stop on the bogie pivot
In most cases, bump stops are located in the lateral axis of the bogie pivot. Their design can vary, generally
they use an elastic element to maintain passenger comfort in case of contact. In this case, the deformation
of the latter is included in 𝑤𝑤.
NOTE The amount of deformation to be taken into account depends on the gauging method (see EN 15273-
2:2025).
Figure 9 gives an example of the position of this bump stop.
Key
1 carbody
2 bogie pivot
3 lateral bump stop with elastic element
Figure 9 — Bump stops on the bogie pivot
7.1.1.5.2.2 Curve dependent lateral bump stops
Where present, their purpose is to limit the lateral displacement of the carbody relative to the bogies "𝑤𝑤"
in small radii curves, so as to obtain a wider vehicle.
Figure 10 gives an example of a simple design with which the lateral clearance “w” is dependent of the
bogie rotation in function of the radius of the curve:

Key
1 carbody
2 bogie
3 bump stops beyond the pivots (clearance 𝑤𝑤 )
𝑎𝑎,(𝑅𝑅)
4 bump stops between the pivots (clearance 𝑤𝑤 )
𝑖𝑖,(𝑅𝑅)
5 bogie centreline
6 carbody centreline
7 bogie pivot
Figure 10 — Example of lateral bump stops
The bump stops located beyond bogie pivots limit the displacement outside the curve (𝑤𝑤 ), those
𝑎𝑎
between pivots limit the displacement inside the curve (𝑤𝑤 ).
𝑖𝑖
Key
1 centreline of the track
2 centreline of the carbody
3 centreline of the bogie
4 curve dependent bump stops between bogie pivots
5 curve dependent bump stops beyond bogie pivots
Figure 11 — Displacements of the carbody w and w
i a
Depending on their design, the contact surfaces of these bump stops could be simple (flat bump stops) or
more complex.
Figure 12 gives an example of a vehicle with progressive bump stops.

Figure 12 — Example of a vehicle with progressive bump stops
7.1.1.5.3 Calculation principle
As mentioned in EN 15273-2:2025, A.3.3 the value of lateral clearance between the carbody and the
bogies is determined for a position of the longitudinal axis of the bogie centred in the track. In order to
simplify the process, only the geometrical rotation Δ of the bogie is taken into account, but not the skew
of the bogie and the carbody.
Key
1 centreline of the track
2 centreline of the bogie
Figure 13 — Rotation angle of the axis of the bogie according to the track radius
The value of the angle Δ can be calculated using the following simplified formula:
𝑎𝑎
𝑠𝑠𝑠𝑠𝑠𝑠∆=
2𝑅𝑅
NOTE In this calculation, the effect due to geometric overthrow of the bogie does not affect the angle ∆ value.
Figure 14 illustrates the evolution of the lateral clearance between the stops and bogies frame depending
on the variation of the angle ∆:
Key
1 path of the bogie frame
2 lateral clearance w in a large curve
i
3 lateral clearance w in a medium curve
i
4 lateral clearance wi in a tight curve
Figure 14 — Lateral clearance 𝒘𝒘 in a curved track
𝒊𝒊
When analysing the lateral displacement of the carbody as a function of the curvature of the track (1/𝑅𝑅),
the contribution of each bump stop is determined.
For a given curve radius, only the maximum value of 𝑤𝑤 applies for the determination of static and
kinematic gauges.
This approach determines the radii at which a "discontinuity point" appears (point 4 in Figure 15). This
discontinuity point shows the change of lateral bump stop behaviour at which the bump stop on the bogie
pivot limits the lateral displacement for smaller curve radii.
Figure 15 gives an example of this variation law of 𝑤𝑤 or 𝑤𝑤 as a function of 1/𝑅𝑅.
𝑖𝑖 𝑎𝑎
Key
1 bump stops at bogie pivot
2 curve dependent bump stops between bogie and carbody for a linear form
3 curve dependent bump stops between bogie and carbody for a progressive form
4 discontinuity point (change in the bump stop to be taken into account)
Figure 15 — Lateral clearance "w" according to the curve radius
The discontinuity points give the supplementary critical radii 𝑅𝑅 for the calculation of the gauge.
7.1.1.6 The quasi-static roll defined by the kinematic gauges (justification)
𝐷𝐷 𝐼𝐼
The full quasi-static roll is 𝑄𝑄 =𝑠𝑠∙ ∙ |ℎ−ℎ | for inside the curve or 𝑄𝑄 =𝑠𝑠∙ ∙ |ℎ−ℎ | for outside the
𝑐𝑐 𝑐𝑐
𝐿𝐿 𝐿𝐿
curve.
The Railway Undertaking takes into account a value 𝑧𝑧 inside the reference profile and the
𝑐𝑐𝑖𝑖𝑐𝑐
Infrastructure Manager takes into account 𝑞𝑞𝑠𝑠 outside the reference profile. 𝑄𝑄 =𝑧𝑧 +𝑞𝑞𝑠𝑠.
𝑐𝑐𝑖𝑖𝑐𝑐
For 𝐷𝐷≤𝐷𝐷 and 𝐼𝐼≤𝐼𝐼 , no quasi-static roll is taken into account by infrastructure.
0 0
For 𝐷𝐷 >𝐷𝐷 or 𝐼𝐼 >𝐼𝐼 , the value 𝑞𝑞𝑠𝑠 taken into account by the infrastructure depends on the height ℎ >ℎ
0 0 𝑐𝑐0
for the value 𝑠𝑠 . No quasi-static roll is taken into account by infrastructure for ℎ ≤ℎ .
0 𝑐𝑐0
The value 𝑧𝑧 depends on 𝑠𝑠 and ℎ of the vehicle under consideration, the height ℎ and the fixed values
𝑐𝑐𝑖𝑖𝑐𝑐 𝑐𝑐
of 𝐷𝐷 or 𝐼𝐼 .
0 0
For ℎ≥ℎ the entire quasi-static roll is taken into account by the Railway Undertaking with 𝐷𝐷 or 𝐼𝐼 and
𝑐𝑐0 0 0
𝐷𝐷 or 𝐼𝐼 .
𝑚𝑚𝑎𝑎𝑚𝑚 𝑚𝑚𝑎𝑎𝑚𝑚
For the lower parts of a non-tilting vehicle, the roll effect 𝑧𝑧 in direction opposite to the clearances 𝑞𝑞 +
𝑐𝑐𝑖𝑖𝑐𝑐
𝑤𝑤 is not taken into account by the rolling stock for ℎ ≤ℎ , because 𝑞𝑞 +𝑤𝑤 is considered to be bigger.
𝑐𝑐
NOTE Nevertheless in lower parts, for vehicle with 𝑠𝑠 >𝑠𝑠 , it is verified and the possibility to have 𝑧𝑧 higher
0 𝑐𝑐𝑖𝑖𝑐𝑐
than 𝑞𝑞 +𝑤𝑤 is taken into account. See A.3.2.4 in EN 15273-2:2025.
Key
1 clearance 𝑞𝑞 +𝑤𝑤
2 value 𝑧𝑧 in the opposite direction
𝑐𝑐𝑖𝑖𝑐𝑐
Figure 16 — Taking into account the roll effect in the lower parts of non-tilting rolling stock
The division of the roll effect between the infrastructure and non-tilting rolling stock for different
conditions is illustrated in Figure 17, Figure 18 and Figure 19.

Key
1 value 𝑧𝑧 taken into account by the rolling stock
𝑐𝑐𝑖𝑖𝑐𝑐
2 value 𝑞𝑞 taken into account by the Infrastructure Manager
𝑠𝑠
Figure 17 — Agreement in the division of the roll effect between infrastructure and non-tilting
rolling stock
Key
1 𝑧𝑧 calculated with the value s of the candidate vehicle and 𝐷𝐷 or 𝐼𝐼 , taken into account by the rolling stock
𝑐𝑐𝑖𝑖𝑐𝑐 0 0
2 𝑞𝑞𝑠𝑠 calculated with the value s and (𝐷𝐷−𝐷𝐷 ) or (𝐼𝐼−𝐼𝐼 ) , taken into account by the infrastructure
0 0 >0 0 >0
3 supplementary 𝑧𝑧 calculated with the value (𝑠𝑠−𝑠𝑠 ) and 𝐷𝐷 −𝐷𝐷 or 𝐼𝐼 −𝐼𝐼 , taken into account by the
𝑐𝑐𝑖𝑖𝑐𝑐 0 >0 𝑚𝑚𝑎𝑎𝑚𝑚 0 𝑚𝑚𝑎𝑎𝑚𝑚 0
rolling stock
Figure 18 — Agreement between infrastructure and non-tilting rolling stock
when 𝒔𝒔 >𝒔𝒔 and 𝒉𝒉 =𝒉𝒉
𝟎𝟎 𝒄𝒄 𝒄𝒄𝟎𝟎
a) b)
Key
1 𝑧𝑧 calculated with the value s of the candidate vehicle and 𝐷𝐷 or 𝐼𝐼 (hatched area taken into account by the
𝑐𝑐𝑖𝑖𝑐𝑐 0 0
rolling stock)
2 𝑞𝑞𝑠𝑠 calculated with the value s and (𝐷𝐷−𝐷𝐷 ) or (𝐼𝐼−𝐼𝐼 ) (taken into account by the infrastructure)
0 0 >0 0 >0
3 supplementary 𝑧𝑧 calculated with the value (𝑠𝑠−𝑠𝑠 ) and 𝐷𝐷 −𝐷𝐷 or 𝐼𝐼 −𝐼𝐼 (hatched area taken into
𝑐𝑐𝑖𝑖𝑐𝑐 0 >0 𝑚𝑚𝑎𝑎𝑚𝑚 0 𝑚𝑚𝑎𝑎𝑚𝑚 0
account by the rolling stock)
Figure 19 — Agreement between infrastructure and non- tilting rolling stock when 𝒉𝒉 >𝒉𝒉 and
𝒄𝒄 𝒄𝒄𝟎𝟎
𝒔𝒔 >𝒔𝒔
𝟎𝟎
General case if 𝑞𝑞 +𝑤𝑤 >𝑧𝑧 in the opposite direction for Figure 19:
𝑐𝑐𝑖𝑖𝑐𝑐
The z roll effect in the lower parts a
...