Rail Vehicle Structures - RSSB Iss 1.pdf · GMGN2687 Iss 1 and GMGN2689 Iss 2 with effect from 07/03/2020. Part 1 Purpose and Introduction 1.1 Purpose 1.1.1 This document sets out

Rail Industry StandardRIS-2780-RSTIssue: OneDate: March 2020

Rail Vehicle Structures

Synopsis

This document sets out requirementsand guidance for the design of railvehicle structures.

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Published by RSSB

© Copyright 2020Rail Safety and Standards Board Limited

Uncontrolled when printed New Rail Industry Standard. Supersedes in part, GMRT2100 Iss 5 and inherits guidance from GMGN2685 Iss 1, GMGN2686 Iss 1,

GMGN2687 Iss 1 and GMGN2689 Iss 2 with effect from 07/03/2020

Issue record

Issue Date Comments

One March 2020 Original document

Revisions have not been marked by a vertical black line in this issue because this is anew document.

Superseded documents

The following Railway Group documents are superseded, either in whole or in part asindicated:

Note: The listed documents are superseded by the combination of GMRT2100issue six and RIS-2780-RST issue one.

Superseded documents Sections superseded Date whensections aresuperseded

GMGN2685 issue one All 06/06/2020



GMGN2689 issue two All 06/06/2020

GMRT2100 issue five All 06/06/2020

Supply

The authoritative version of this document is available at www.rssb.co.uk/railway-group-standards. Enquiries on this document can be submitted through the RSSBCustomer Self-Service Portal https://customer-portal.rssb.co.uk/

Rail Industry StandardRIS-2780-RSTIssue: OneDate: March 2020 Rail Vehicle Structures

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Contents

Section Description Page

Part 1 Purpose and Introduction 51.1 Purpose 51.2 Introduction 51.3 Application of this document 61.4 Health and safety responsibilities 71.5 Structure of this document 71.6 Approval and authorisation of this document 7

Part 2 Vehicle design 82.1 Loading 82.2 Fatigue 92.3 Coupling system design 122.4 Body-mounted equipment 182.5 Lifeguards 202.6 Barrier and translator vehicles 22

Part 3 Elements interfacing with passengers and traincrew 233.1 Missile protection 233.2 Bodyside windows 243.3 External handrails 263.4 Gangways 273.5 Aerodynamic loads on passengers and traincrew 28

Part 4 Wheelskates 294.1 Vehicle compatibility 294.2 Infrastructure compatibility 304.3 Wheeskate structures 314.4 Wheelskate wheel geometry 324.5 Wheelskate operational limits 33

Part 5 General design considerations 345.1 Primary and secondary elements 345.2 Material selection 355.3 Structural material properties 355.4 Calculations and analysis 375.5 Bolted joints 37



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5.6 Bonded joints 385.7 Effect of glazing 385.8 Vehicle categories 385.9 Freight vehicles 395.10 Passengers and payload 395.11 Static and fatigue loading 405.12 Lifting and jacking 415.13 Collision loads 435.14 Obstacle deflectors 455.15 Body-mounted equipment 455.16 General considerations for bogies 47

Appendices 49Appendix A Derivation of load cases 49Appendix B Bodyside windows - small missile test procedure for toughened

glass 51

Definitions 53

References 57


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Part 1 Purpose and Introduction

1.1 Purpose

1.1.1 This document sets out requirements for the structural design of rail vehicles.

1.1.2 The principles of structural integrity as applied to rail vehicles are to reduce the risksof damage to the vehicle; this can lead to damage to the infrastructure, and in turn toinjuries to staff, passengers or third parties.

1.1.3 This document is intended to be read in conjunction with the Locomotive andPassenger Rolling Stock Technical Specification for Interoperability (LOC & PAS TSI),the Persons of Reduced Mobility (PRM) TSI, the Rolling Stock - Freight Wagons (WAG)TSI, BS EN 12663, BS EN 13749, BS EN 14752, BS EN 15227, BS EN 15663,BS EN 16286, BS EN 16404, and GMRT2100 issue six. There are requirements for railvehicle structures within these documents that are not duplicated. This RIS sets outadditional requirements for the standardisation of rail vehicle structural integritywithin the rail industry of Great Britain (GB).

1.1.4 The LOC & PAS TSI sets out mandatory requirements for rail vehicle structures andrequires compliance with BS EN 12663, BS EN 13749 and BS EN 15227.

1.1.5 The PRM TSI sets out additional mandatory requirements for rail vehicles, particularlyrelating to accessibility for all passengers.

1.1.6 The WAG TSI sets out mandatory requirements for freight wagons, and requirescompliance with BS EN 12663 and BS EN 13749.

1.1.7 This RIS sets out requirements that are considered useful to the GB rail industry, andaddresses points in BS EN 13749 and BS EN 16286 that are permitted to be specifiedin the technical specification.

1.1.8 Appendix A sets out good practice for the derivation of load cases from test or servicedata.

1.1.9 This document is complementary to issue six of Railway Group Standard GMRT2100,which sets out National Technical Rules for vehicle structural integrity and interiorpassive safety.

1.1.10 This document can be adopted by Railway Undertakings (RUs), vehicle manufacturersand suppliers of rail vehicle components under their respective safety/qualitymanagement system or when specifying products and services.

1.2 Introduction

1.2.1 The scope of vehicle structural design includes:

a) Bodyshell (Parts 2 and 5 of this document):

i) couplers (section 2.3 of this document);ii) body-mounted equipment, including bogie attachments (see section 2.4 of

this document and BS EN 12663);iii) lifting and jacking (see section 5.12 of this document and BS EN 16404);



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iv) aerodynamic loads (see GMRT2100);v) missile protection (see section 3.1 of this document); andvi) structural crashworthiness (see BS EN 15227).

b) Bogies (see section 5.16 of this document):

i) static and dynamic loading (see also BS EN 13749);ii) bogie-mounted equipment (see also BS EN 13749);iii) axleboxes; andiv) lifeguards (see section 2.5 of this document, the LOC & PAS TSI and

BS EN 15227).c) Elements interfacing with passengers and traincrew (Part 3 of this document)

i) windscreens (see also BS EN 15152);ii) windows (see also GMRT2100);iii) doors, steps and external handrails (see also BS EN 14752);iv) gangways (see also BS EN 16286); andv) seats, tables, internal handrails, grab poles, luggage racks etc. (see

GMRT2100).

1.2.2 The mandatory requirements set out in the LOC & PAS TSI are summarised as follows:

a) BS EN 12663 sets out requirements for the static and fatigue strength of thevehicle structure and mounted equipment, depending on the vehicle type (e.g.locomotives, coaches, rapid transit, metros, trams and freight vehicles);

b) BS EN 15227 sets out requirements for structural passive safety, includingobstacle deflectors and lifeguards (see also section 4 of this document);

c) BS EN 16404 sets out requirements for jacking and lifting;d) BS EN 14752 sets out requirements for passenger doors;e) BS EN 15152 sets out requirements for windscreens;f) BS EN 15663 sets out requirements for determining the mass of the vehicle and

payload / passengers; andg) BS EN 13749 sets out requirements for bogie frames.

1.2.3 In addition, GMRT2100 sets out requirements for interior passive safety.

1.2.4 Appendix A of this document supports BS EN 12663 by detailing GB custom andpractice for the derivation of load cases from test or service data.

1.3 Application of this document

1.3.1 Compliance requirements and dates have not been specified because these are thesubject of internal procedures or contract conditions.

1.3.2 If you plan to do something that does not comply with a requirement in this RIS, youcan ask a Standards Committee to comment on your proposed alternative. If youwant a Standards Committee to do this, please submit your deviation applicationform to RSSB. You can find advice and guidance on using alternative requirements onRSSB’s website www.rssb.co.uk.


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http://www.rssb.co.uk

1.4 Health and safety responsibilities

1.4.1 Users of documents published by RSSB are reminded of the need to consider theirown responsibilities to ensure health and safety at work and their own duties underhealth and safety legislation. RSSB does not warrant that compliance with all or anydocuments published by RSSB is sufficient in itself to ensure safe systems of work oroperation or to satisfy such responsibilities or duties.

1.5 Structure of this document

1.5.1 This document sets out a series of requirements that are sequentially numbered. Thisdocument also sets out the rationale for the requirement, explaining why therequirement is needed and its purpose and, where relevant, guidance to support therequirement. The rationale and the guidance are prefixed by the letter ‘G’.

1.5.2 Some subjects do not have specific requirements but the subject is addressed throughguidance only and, where this is the case, it is distinguished under a heading of‘Guidance’ and is prefixed by the letter ‘G’.

1.6 Approval and authorisation of this document

1.6.1 The content of this document was approved by Rolling Stock Standards Committeeon 14 February 2020.

1.6.2 This document was authorised by RSSB on 27 February 2020.



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Part 2 Vehicle design

2.1 Loading

2.1.1 Vehicle structures and substructures shall be designed to:

a) withstand foreseeable loads in normal service, such as twist;b) withstand loads arising under degraded conditions, such as failed suspension

components and derailments; andc) collapse in a controlled and predictable manner when overloaded.

Rationale

G 2.1.2 These requirements are relevant to clause 4.2.2.7 of the LOC & PAS TSI and clause4.2.2 of the WAG TSI. They reduce the risks of injury and excessive structural damageand reflect GB practice.

Guidance

G 2.1.3 Guidance on freight vehicle design is set out in GMGN2688; GB practice is to usemore onerous load cases than set out in BS EN 12663-1:2010+A1:2014,BS EN 12663-2:2010 and BS EN 13749:2011.

G 2.1.4 Twist load cases specified in BS EN 16404:2014 are only for lifting and jacking; bodytwist may also be encountered due to track features.

G 2.1.5 Vehicles are not usually designed for sustained operation under worst-caseconditions. The proof and ultimate load cases set out inBS EN 12663-1:2010+A1:2014, BS EN 12663-2:2010 and BS EN 13749:2011 areintended to define limiting cases for loading, but these cases are expected to occur soinfrequently that they will not affect fatigue load cases for cyclic loading in normaloperation.

G 2.1.6 The load case examples for bogies set out in Annexes C and D of BS EN 13749:2011are not necessarily fully representative of GB operation; see the last paragraph ofAnnex B of BS EN 13749:2011.

G 2.1.7 For operation under degraded conditions, to determine appropriate numbers of cycleswhere higher than normal loadings may be encountered, it is good practice to takeaccount of:

a) the maintenance regime; andb) systems or methods for detection of fault conditions.

Note: BS 7608:2014+A1:2015 clause 16.1 suggests no more than 100cycles exceeding 'normal operating conditions' (80% of yield stress remotefrom stress concentrations) over the anticipated life of the structure. Higherstresses and / or greater numbers of cycles may therefore need to beincluded in fatigue damage calculations.

G 2.1.8 Generally, the load values set out in the referenced European Standards are well-established and will result in acceptable performance for a wide range of vehicleapplications. It is however permissible to determine alternative load cases for a railvehicle or component, by either:


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a) using established engineering methods from test data (see Appendix A) andvalidated calculations; or

b) demonstrating equivalence between applications, using service experience tojustify a design feature.

G 2.1.9 It is good practice to undertake a thorough assessment of likely loading cycles overthe vehicle life, based, wherever possible, on service data and operational experience,and to undertake the vehicle body fatigue analysis using this set of fatigue loadcases.

G 2.1.10 Based on suspension frequencies in the range 0.5 Hz to 2.0 Hz, a railway vehicle bodytypically sees around 109 cycles in a 30-year life. Fatigue load cases therefore need tobe specified in a manner that is consistent with the fatigue code being used. However,the fatigue load cases specified in BS EN 12663-1:2010+A1:2014 andBS EN 12663-2:2010 for 107 cycles are generally considered sufficient for designpurposes.

G 2.1.11 For materials traditionally used in vehicle construction, use of the proof (1.15) andultimate (1.5) factors set out in BS EN 12663-1:2010+A1:2014, BS EN 12663-2:2010and BS EN 13749:2011 are usually sufficient to control material behaviour underoverload conditions.

2.2 Fatigue

2.2.1 Rail vehicle structures and substructures, including bodyshells, bogies andattachments, shall be designed to achieve their required fatigue life with a survivalprobability of at least 97.5%, when subjected to the cyclical loads associated withnormal operation.

2.2.2 Fatigue life assessments shall use the cumulative damage method, unless theendurance limit approach can be technically justified.

2.2.3 For lateral fatigue loadings on equipment attached to freight vehicles set out in Table16 of BS EN 12663-1:2010+A1:2014 or Table 16 of BS EN 12663-2:2010, thereduction permitted by Note a) to these tables shall be applied.

Rationale

G 2.2.4 This requirement supports clause 4.2.2.4 (3) of the LOC & PAS TSI and clause 4.2.2 ofthe WAG TSI. Fatigue requirements for rail vehicle structures are given in:

a) section 6.6. of BS EN 12663-1:2010+A1:2014;b) section 5.2.5 of BS EN 12663-2:2010; andc) Annex E of BS EN 13749:2011;

as called up by the LOC & PAS TSI and the WAG TSI.

Guidance

G 2.2.5 Fatigue design codes generally use mean minus two standard deviation data whichgives a 97.5% probability of survival. It is understood that the 95% probability statedin BS EN 13749:2011 is also based on mean minus two standard devation fatiguedata.



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G 2.2.6 Historically, GB rolling stock has typically been designed using BS 7608:1993 orBS 8118-1:1991, applying Miner’s law to sum the fatigue damage from different loadcases to give an overall prediction of fatigue life.

G 2.2.7 The endurance limit methods set out in BS EN 12663-1:2010+A1:2014,BS EN 12663-2:2010 and BS EN 13749:2011 for fatigue assessment may be usedsubject to provision of evidence of satisfactory performance under GB operatingconditions, for example, data from on-track testing to validate loading assumptions.

G 2.2.8 GB practice is to use BS EN 12663-1:2010+A1:2014 for freight vehicles, as themethods in BS EN 12663-2:2010 may lead to a less robust design.See also G 2.1.6.

G 2.2.9 A lateral fatigue acceleration range of ±0.2 g for 107 cycles is an established value forequipment attached to freight vehicles operating in GB conditions.

G 2.2.10 The required fatigue life is not necessarily the service life of the vehicle, provided asuitable inspection and maintenance regime is in place to manage the risksassociated with life-expired components. General maintenance requirements are setout in the LOC & PAS TSI; specific maintenance requirements for bogies are set out inBS EN 15827:2011.

G 2.2.11 An acceptable fatigue life can be achieved by the application of national or Europeanstructural fatigue codes such as:

a) BS EN 1993-1-9:2005 (Eurocode 3 – see G 2.2.12);b) BS EN 1999-1-3:2007+A1:2011 (Eurocode 9 – see G 2.2.12);c) BS 7608:2014+A1:2015; andd) BS 8118-1:1991 (superseded).

This list is not exhaustive; other national standards can be used.

G 2.2.12 Refer to the UK national annexes to the Eurocodes and PD 6702-1 for detailedguidance (the status of these documents will need to be checked before use). There isa risk that the direct application of the fatigue curves set out in BS EN 1999-1-3:2007,which permits higher stress levels than used in GB practice, could result inunsatisfactory or potentially dangerous structural details.

G 2.2.13 However, many of these fatigue codes have been developed for relatively largestructures such as bridges. In applying these codes to rail vehicle structural design,note that they are generalised in nature. Where ‘thin’ materials are being analysed,the assumptions made by these codes for material thicknesses, weld quality andresidual stress levels may lead to very conservative conclusions.

G 2.2.14 A European Standard for determining fatigue life using cumulative damage for railvehicles is currently in preparation (prEN 17149).

G 2.2.15 Where it is intended to adopt different methods for the verification of the fatiguedesign, it is good practice to assess carefully the fatigue load cases and ensure thatthe load combinations are consistent with the fatigue acceptance criteria. If usingmethods other than the cumulative damage method, it is good practice to ensurethat the results are representative of the real service conditions and the way theresults are considered are consistent with the acceptance criteria used.


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G 2.2.16 The service fatigue life for any given structural item will be the combined effect of theappropriate analysis of loadings, stresses and fatigue together with its manufacture,assembly and operation.

G 2.2.17 It is good practice to ensure that all these aspects are dealt with in a mutuallyconsistent manner. See clause 7.3 of BS EN 12663-1:2010+A1:2014, andBS EN 15085-3:2007.

G 2.2.18 Many fatigue curves, developed for classical calculation methods, have alreadyaccounted for stress concentration effects, either fully or in part. It is good practice toexercise care when interpreting the results of detailed finite element calculationswhere localised high stresses occur.

G 2.2.19 It is generally permissible within these codes to develop fatigue curves fromexperimental data for particular details; in some cases, this will be highly beneficial interms of structure weight and cost. Where experimental data is used to developbespoke fatigue curves, it is good practice to include full documentation of the rawdata and its post-treatment (see Appendix A).



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2.3 Coupling system design

2.3.1 Couplers

2.3.1.1 Where compatibility with existing GB rolling stock is required, the coupling systemshall be chosen from those already in use on vehicles operating on GB infrastructure.

2.3.1.2 The coupling system, with the exception of buffers, shall engage positively with thecoupling system of any rail vehicle to which it is intended to couple in a train.

2.3.1.3 The design of the system shall ensure that it is possible to determine that thecoupling systems are positively engaged, either directly or by a suitable system ofindication.

2.3.1.4 The limiting track features which affect the operation of coupling systems shall beidentified. Typically, these will include:

a) Minimum horizontal track radius;b) Minimum horizontal track reverse radius with a 3 m intermediate straight;c) Minimum vertical track radius, concave and convex;d) Maximum installed cant;e) Maximum cant gradient; andf) Maximum track twist.

2.3.1.5 The coupling systems, with the exception of buffers, shall remain positively engagedduring all normal operations of the rail vehicles over the track features that they arerequired to negotiate.

2.3.1.6 Coupling and uncoupling shall be possible over the applicable range of track featuresfor the particular vehicles.

2.3.1.7 Any system that controls the operation of the coupling or uncoupling system shall beprotected from reasonably foreseeable interference that could result in the system’sinadvertent or malicious operation.

2.3.1.8 The coupling system design shall ensure that it is possible to arrange manualuncoupling if the systems normally required for uncoupling are unavailable, whilstprotecting against inadvertent or malicious operation.

2.3.1.9 Adaptor couplings or coupling components shall be designed to ensure safe handling,assembly or disassembly by traincrew.

Rationale

G 2.3.1.10 These requirements ensure technical compatibility with the GB mainlineinfrastructure and legacy rolling stock. Further:

a) The requirements in clause 4.2.2.2.3 (b-1) of the LOC & PAS TSI apply only to the"UIC type" as defined in clause 5.3.2 of the LOC & PAS TSI;

b) The requirements in clause 4.2.2.2.3 (a-2) of the LOC & PAS TSI for end couplingsystems apply only to the "Type 10 latch system automatic centre buffer coupler"as defined in clause 5.3.1 of the LOC & PAS TSI; and

c) Other types of coupler are not an Interoperability Constituent; see clause 5.3 ofthe LOC & PAS TSI.


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Guidance

G 2.3.1.11 General requirements for couplings are set out in section 4.2.2.2 of the LOC & PAS TSIand section 4.2.2.1 of the WAG TSI. See also RIS-2790-RST.

G 2.3.1.12 The GB interpretation of 'the forces due to the intended operating conditions' in theLOC & PAS TSI includes:

a) coupling and uncoupling;b) traction and braking;c) traversing curved track;d) vertical changes in alignment; ande) shock loads caused by play and flexibility in the train coupling, drawgear and

buffers, if fitted.

G 2.3.1.13 Various types of coupling systems are in use, each of which provides a variety of basicfunctions:

a) Connecting and separating vehicles either by manual or automatic methods;b) Transferring tensile and compressive traction and braking forces between vehicles

during operation;c) Accommodating relative movements between adjacent vehicles; andd) Where required, automatic connection and disconnection of power, control,

communication and air supplies between vehicles.

G 2.3.1.14 In addition to the above, many coupling systems incorporate additional functions,which may include:

a) recoverable energy absorption for coupling and rough shunting or minor collisions,whilst limiting injury to passengers and traincrew and without damage to vehicleequipment and structures;

b) high levels of resistance to overriding and separation of vehicles during collisionsand derailments; and/or

c) non-recoverable collapse of the coupling equipment or its connecting structure insevere collisions, to allow engagement of anti-climbers or bodyends as part of acontrolled system of progressive collapse.

G 2.3.1.15 The coupling systems types in current use in GB can be broadly classified as:

a) vehicles fitted with side buffers, drawhooks and screw or link couplers (includingUIC couplings);

b) manually convertible vehicles fitted with side buffers, drawhooks and eitherdrophead buckeye automatic couplers or swinghead couplers;

c) automatic centre couplers (Tightlock, BSI, Scharfenberg etc); andd) semi-permanent (bar) couplers (for use within a fixed rake or unit).

See dataset SD001(2014) for a list of GB legacy coupling systems.

G 2.3.1.16 GB practice is to include information regarding the limiting values of track features aspart of the assessment for Route Compatibility using RIS-8270-RST.



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G 2.3.1.17 The values given in Table 1 are representative of limiting cases that can be found onthe GB mainline railway. It is not, however, a requirement that every vehicle has to becapable of operating under these conditions.

G 2.3.1.18 It is established practice to identify the minimum radius curve the vehicle cantraverse within the certification issued as part of the authorisation for placing avehicle into service.

G 2.3.1.19 It is good practice to ensure that all couplings are capable of accepting the worst-case track for which the vehicle is designed, taking into account applicablemaintenance limits.

G 2.3.1.20 When considering the selection or the introduction of coupler systems, it is goodpractice to consider the following aspects, in addition to the mandatory requirementsset out in legislation and Railway Group Standards:

a) Operating and performance requirements;b) Inter-working requirements with existing types of vehicles where applicable;c) Any requirement to prevent connection to existing types of vehicle which are

incompatible for normal service operation;d) Requirements for rescue and assistance with other vehicles; ande) Requirements for transit movements to workshops and maintenance facilities and

to allow for shunting.

G 2.3.1.21 When designing manual coupling systems, it is good practice to ensure compatibilitywith existing systems on vehicles to which they could reasonably be expected to becoupled. Historically, to maximise payload or useable capacity, it has been GBpractice to design longer vehicle bodies to compensate for the restrictions on widthcompared with equivalent European vehicles. Therefore, buffers for vehicles solely foruse in GB have a tighter buffer head radius than standard mainland Europeanbuffers; shorter overall length and longer buffer strokes are also sometimes used. Theuse of incompatible buffers could lead to excessive longitudinal compressive forcesand / or drawbar loads.

G 2.3.1.22 GB practice is to use permanent fixed bar couplers in fixed formation units, tominimise the risk of vehicles parting. These risks are increased where vehicles arefitted with open gangways, due to the lack of vehicle end doors. Mechanical auto-couplers are known to have become unlatched and parted in accidents andderailments.

G 2.3.1.23 Where the structure gauge is limited, large movements of vehicles out of linesignificantly increases the risk of impacts against fixed structures or a roll-over. GBpractice is to limit coupler movements as far as possible while satisfying alloperational requirements, thus minimising misalignment between vehicles in theevent of a collision or derailment. Limiting coupler movements can also assist inresisting override.

G 2.3.1.24 Positive engagement means that a coupler, once engaged, will remain connectedunder all service loading conditions until specifically required to be uncoupled.

G 2.3.1.25 See also section 5.13 regarding coupler performance in collisions.


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Track Feature Value

Nominal track gauge (new and re-laid track) 1,435 mm

Gauge widening, curve radii 100 m to 141 m 7 mm



Minimum horizontal track radius:

Mainline 120 m

Non-passenger lines and sidings

Note that certain freight vehicles may be required to operateon curves of 70 m radius; tighter radii may be encountered oninfrastructure that is not managed by Network Rail

90 m

Minimum horizontal track reverse radius with a 3 m intermediate straight:

Mainline 140 m

Non-passenger lines and sidings 120 m

Minimum vertical track radius, concave or convex:

Mainline 500 m

Non-passenger lines and sidings 200 m

Maximum installed cant 200 mm

Maximum cant gradient 1 in 400

Maximum rate of change of cant 85 mm/s

Maximum cant deficiency 6°

Maximum rate of change of cant deficiency 70 mm/s

Table 1: Representative limiting values for track alignment and geometry

2.3.2 Drawgear

2.3.2.1 The drawgear and its attachment to a vehicle body shall be designed to deform in acontrolled manner at a tensile load below the design load of the primary structure.

2.3.2.2 Drawgear, and its attachment to a vehicle body, shall be designed to contribute to, ornot conflict with, the requirements for body structural collapse and energy absorption.



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2.3.2.3 Drawgear designed to be capable of transferring shear forces between adjacentvehicles shall withstand without significant permanent deformation the transfer of100 kN in both the vertical and transverse directions simultaneously.

Rationale

G 2.3.2.4 See G 2.3.1.10. These requirements also support clause 4.2.2.5 of the LOC & PAS TSIand clause 4.2.2 of the WAG TSI, and can be used in support of compliance withBS EN 15227:2008+A1:2010 (or BS EN 15227:2020 when published). They addressthe risks of costly repairs following low-speed collisions and of vehicle separationduring collision or derailment and reflect GB practice.

Guidance

G 2.3.2.5 The selection of the force levels for drawgear collapse and break-out can have asignificant effect on collision dynamics. Research indicates that low drawgearcollapse forces will improve the stability of a rake of vehicles in a head-on collision.Low collapse forces however will increase the risk of damage from heavy shunts andminor collisions.

G 2.3.2.6 There is no requirement for the drawgear compressive strength or limiting break-outload to be as high as the load capacity of the vehicle underframe at the couplermounting positions.

G 2.3.2.7 It is good practice to ensure that the tensile failure load for the drawgear is lowerthan the specified bodyshell proof load, taking into account tolerances and variationsdue to manufacture and assembly. Higher drawgear failure loads would mean theunderframe structure would need to be designed for a higher tensile load, in excess ofthe minimum proof load specified for the vehicle.

G 2.3.2.8 It is good practice to find an acceptable compromise for drawgear compressivestrength, taking into account the intended operation of the vehicles.

G 2.3.2.9 In the case of break-out drawgear, it is good practice to determine where theboundary between the drawgear and bodyshell structure lies, which will be subject tothe mechanism adopted. Break-out mechanisms are typically based on a number ofbolts failing in direct shear or by pulling through collars in tension.

G 2.3.2.10 It is good practice to evaluate the compressive characteristics of drawgear as part ofthe collision energy management strategy that is required to satisfy thecrashworthiness requirements. Typically, a crashworthy vehicle’s drawgear operatesin three distinct modes:

a) recoverable elastic stroke, which may be rate-sensitive;b) controlled longitudinal collapse; andc) deformation and coupler break-out.

G 2.3.2.11 Although all good coupler designs will withstand the forces acting in tension, onlycertain types of automatic coupler and bar couplers are capable of fully complyingwith the requirement to transfer 100 kN in vertical and transverse directions.

G 2.3.2.12 Where automatic coupler and bar couplers are used, it is good practice to match thedesign of the underframe to the design of the drawgear, and to cater for any


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additional bending loads induced when the drawgear blocks out against its limitstops.

G 2.3.2.13 See also 5.13 for drawgear performance in collisions.

2.3.3 Buffers

2.3.3.1 Design

2.3.3.1.1 The height of the centre line of the buffers, under all permitted conditions of wheelwear, shall be:

a) a maximum of 1065 mm above rail level in the tare condition; andb) a minimum of 940 mm above rail level in the crush condition.

2.3.3.1.2 Buffers shall be designed to enable safe operation of the rail vehicles over the rangeof track features that they are required to negotiate, without buffer interlocking.

Rationale

G 2.3.3.1.3 See G 2.3.1.10. These requirements control the risk of buffer interlocking.

Guidance

G 2.3.3.1.4 See also the GB National Foreword to BS EN 15551:2017.

G 2.3.3.1.5 PD CEN/TR 17373:2019 sets out a methodology for assessing buffer interlocking, butthe specific scenarios do not necessarily apply to GB infrastructure.

2.3.3.2 Static loads

2.3.3.2.1 The strength of buffers and their attachments to the vehicle body shall:

a) under axial load, be the same as the longitudinal compressive strength specifiedat the buffer positions on vehicle bodies; and

b) include all expected eccentric loads due to relative misalignment betweenadjacent vehicles in normal use.

Rationale

G 2.3.3.2.2 See G 2.3.1.10. This requirement controls the risks of buffer structural failure inoperation.

Guidance

G 2.3.3.2.3 The longitudinal compressive loads for buffer positions on vehicle bodies are specifiedin BS EN 12663-1:2010+A1:2014 and BS EN 12663-2:2010.

G 2.3.3.2.4 Eccentric loadings arise on buffers, their mountings and immediately adjacentstructures, due to the wide range of potential inter-vehicle movements and alltransmitted forces, including secondary effects due to relative inclination of vehiclesor curvature of the buffer faces. BS EN 15551:2017 sets out suitable load values andtest methods.



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G 2.3.3.2.5 The UK National Foreword to BS EN 15551:2017 provides guidance on buffer design.

2.3.3.3 Dynamic Loads

2.3.3.3.1 Buffers shall be designed to withstand contact with fixed buffer stops to arrest thetrain speed without damage to the vehicle or the buffer stops.

Rationale

G 2.3.3.3.2 This requirement is for technical compatibility with the GB mainline infrastructure. Itcontrols the hazards of vehicles damaging fixed buffer stops under low speedcollisions and reflects GB historical practice.

Guidance

G 2.3.3.3.3 GB practice is to perform design calculations as follows:

a) Using an impact speed of not less than 7 km/h;b) For passenger vehicles, using the design mass under exceptional payload as set

out in BS EN 15663:2017+A1:2018;c) For freight vehicles, using the design mass under normal payload as set out in

BS EN 15663:2017+A1:2018; andd) It is permissible to assume that 25% of the kinetic energy will be absorbed by the

vehicle and its load.

2.4 Body-mounted equipment

2.4.1 Secondary retention

2.4.1.1 Secondary fasteners, retention devices or some other equivalent means shall beprovided where:

a) the failure of an individual mounting could lead to the overload and the potentialsequential failure of adjacent mountings; or

b) a single mounting is used, and a resulting failure will create a hazardous situation.

2.4.1.2 The need for, and design of, secondary retention shall be determined based on thelikelihood of detection of an initial failure when in service or during maintenanceinspections.

Rationale

G 2.4.1.3 This requirement supports clause 4.2.2.7 of the LOC & PAS TSI and clause 4.2.2.2 ofthe WAG TSI. It addresses the risks of equipment detachment and the potentialconsequence of a derailment and reflects GB practice.

Guidance

G 2.4.1.4 See the Note under clause 5.3.1 of BS EN 12663:2010+A1:2014. It is good practice toensure that single point failure will not result in detachment of equipment in amanner to cause an immediate hazard.


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G 2.4.1.5 Good practice is to assess the need for enhanced equipment retention (secondaryfasteners, retention devices or some other equivalent means) based on the type ofequipment, the potential for failure and the likely consequences of detachment.

G 2.4.1.6 For example, a piece of underframe equipment mounted with a single bolt in each offour corners may be at risk of rapid complete detachment if one bolt fails. This riskcould be addressed, for example, by a fail-safe design or using two (smaller) bolts percorner.

G 2.4.1.7 Examples of suitable methods of enhanced retention could range from substitutinglock-pins for torqued bolts, using additional fasteners for redundancy or to includesecondary retention features such as hooks, catchers, slings or straps to engage whenthe main connection has failed.

G 2.4.1.8 Under some conditions, minor externally mounted items might be impacted by itemsor debris on the track or at the lineside and thus become detached. If sharp edges orcorners can be avoided wherever possible in the detail design, the potential forsecondary impact damage will be minimised.

2.4.2 Minor items

2.4.2.1 For minor items of body mounted equipment, it shall be demonstrated that:

a) for a given type or method of attachment, items at or below a given mass will besecurely retained for the acceleration loads specified; or

b) the minor item is sufficiently contained or enclosed to prevent it becoming apotential hazard if detached in the event of a collision or derailment; or

c) service experience in an equivalent or more demanding environment has shownthe installation to be satisfactory.

Rationale

G 2.4.2.2 These requirements support clause 4.2.2.7 of the LOC & PAS TSI and clause 4.2.2 ofthe WAG TSI. The LOC & PAS TSI refers to BS EN 12663-1:2010+A1:2014, whichrequires the demonstration of compliance "by calculation and/or testing". GB practiceallows less onerous requirements for minor items, instead of calculation using theload cases for body mounted equipment.

Guidance

G 2.4.2.3 Examples of minor items would be equipment or fittings of very low mass attachedusing a generic design of bracket or keyway attachment. In this case, the loadcapacity of the attachment may be determined and thus items which are within thatdesign capacity are generally satisfactory.

G 2.4.2.4 To determine whether an item is a minor item of equipment, it is good practice toassess the consequences of failure. Different criteria may therefore be appropriate fordifferent parts of a vehicle. For example:

a) underframe mounted equipment would require more stringent criteria to beapplied, as detachment could potentially result in derailment;



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b) items mounted inside locked equipment cubicles could be subject to less stringentcriteria, as detached items will be effectively contained, and the possibletrajectories will be inherently limited.

G 2.4.2.5 In assessing the significance of items of equipment, it is good practice to includecareful assessment of vehicle interior fittings. The masses of items such as openablepanels, lighting panels or lighting diffusers are relatively low, but there could be asignificant risk of injury if they become detached or displaced in the event of acollision (see GMRT2100 issue six).

G 2.4.2.6 Where an installation has been used for an extended period in service in a similar ormore arduous environment and has performed satisfactorily, with no records ofconsistent unscheduled maintenance, this can be taken as evidence of acceptableperformance. It is good practice to ensure that, if adopted, this approach isdocumented using a “well-founded technical justification” (see clause 6.1 ofBS EN 12663-1:2010+A1:2014).

2.5 Lifeguards

2.5.1 All leading bogies shall be fitted with lifeguards to meet the requirements in clause4.2.3.7 of the LOC & PAS TSI and clause 6.6 of prEN 15227:2016 (BS EN 15227:2020when published), unless the obstacle deflector meets the associated requirements.

2.5.2 A lifeguard shall be:

a) made of a ductile material;b) able to resist a sustained concentrated proof load of at least 20 kN applied at its

bottom edge horizontally and in a longitudinal direction towards the adjacentwheel, and during deformation beyond the proof load, able to resist an ultimateload of at least 35 kN;

c) able to resist the proof load set out in b) combined with a transverse load, in eitherdirection, of at least 10 kN;

d) designed so that, as the load in b) or c) is increased up to the ultimate ormaximum dynamic load that it can sustain during impact with the obstacle, itdeforms plastically to absorb as much additional energy as reasonably practicable;

e) designed so that, during and after deformation due to the loads specified, it doesnot foul the track or running gear and that contact with the wheel tread, if itoccurs, does not pose the risk of derailment; and

f) designed so that, under the conditions described above, it remains securelyattached to the bogie.

2.5.3 The bogie and the attachment of the lifeguard to the bogie shall not be damaged orsuffer significant permanent deformation under the loads and deflections set outabove.

2.5.4 If mounted on a bogie frame or mounted on an axlebox, the lifeguard and itsattachments shall be capable of withstanding:

a) the applicable proof loads, without significant permanent deformation; andb) the inertia forces associated with all applicable fatigue accelerations, without

failure.


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Rationale

G 2.5.5 These requirements support clause 4.2.3.7 of the LOC & PAS TSI, addressing the riskof damage or derailment from small items on the head of the rail. They represent GBpractice as follows:

a) The wording in the TSI states "This requirement can be met by life guards ..."b) prEN 15227:2016 (BS EN 15227:2020 when published) only requires lifeguards

and obstacle deflectors for design categories C-I and C-III.c) The TSI requires the longitudinal proof load of 20 kN but does not specify a

transverse load or an ultimate load.d) The force values and load combinations for lifeguards were developed by British

Rail and British Rail Research after an extensive series of tests and developmentwork; see RSSB research report T189 (2006).

Guidance

G 2.5.6 It is essential that a lifeguard, when struck by an obstacle, will not itself then becomea danger by:

a) breaking or by otherwise becoming detached or partially detached from the bogie;or

b) deforming in such a way that it could foul the track or running gear.

G 2.5.7 The use of a ductile material minimises the danger of breaking and maximises thecapacity for absorbing the energy of impact.

G 2.5.8 Where a lifeguard is attached to a bogie frame or axlebox, the design of the joint orconnection is usually a critical interface. On many designs of bogie this is a horizontalbolted joint between the lifeguard and the outer end of the axlebox casting. If thelifeguard is impacted and the preload in the joint overcome, some or all of the boltswill be directly loaded in tension. The preparation of the joint surfaces and the correcttensioning of the bolts are therefore critical for this type of installation.

G 2.5.9 While an ultimate load case is specified as a minimum value, a good lifeguard designwould not be so strong as to result in undesirable consequences to the structures onwhich it is mounted, for example, permanent deformation of bogie frames.

G 2.5.10 RSSB research report T189 (2006) gives details of a concept design of lifeguard. Thedesign was developed and prototypes were tested in which a substantial increase inreaction force was gained by locating the lifeguard blade close to the wheel andallowing it to contact the wheel as it deforms under load. The rear face of thelifeguard is shaped so that, when contact is made with the wheel, the lifeguard issupported, and the forces are directly transferred into the wheel. The increase inimpact force that can be resisted by using this approach will enable significantlyheavier obstacles to be removed.

G 2.5.11 A good lifeguard design will ensure, as far as possible, that:

a) the integrity of the joint cannot be compromised due to incorrect assembly orimpacts up to at least the ultimate load case specified;

b) any potentially dangerous defects can be easily detected; and



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c) the effects of track and suspension design are assessed (see G 5.16.3 and clause D.2.3 of BS EN 13749:2011).

G 2.5.12 A robust demonstration that all these factors have been assessed is likely to include aphysical impact test which may be used to validate any non-linear finite elementanalysis.

2.6 Barrier and translator vehicles

2.6.1 It is permissible for barrier vehicles or translator vehicles, intended solely for thepurpose of permitting trains or units to be hauled by otherwise incompatible vehiclesor locomotives, to be designed to the same structural design criteria as the hauledvehicles with which they interface.

2.6.2 It is permissible for structural criteria permitted by 2.6.1 to apply to either thecomplete vehicle or locally where required for non-standard or incompatible drawgearattachment points and associated interfaces on translator vehicles.

2.6.3 The crashworthiness requirements of BS EN 15227:2008+A1:2010 (orBS EN 15227:2020 when published) shall not be applied to barrier or translatorvehicles, where these are intended solely for the purpose of permitting trains or unitsto be hauled by otherwise incompatible vehicles or locomotives.

Rationale

G 2.6.4 These requirements support clause 4.2.2.5 of the LOC & PAS TSI. They address therisks of vehicle damage in collisions and reflect GB practice for the use of barrier andtranslator vehicles.

Guidance

G 2.6.5 This is to ensure that barrier wagons or translator vehicles for use with multiple unitsor metro vehicles (BS EN 12663-1:2010+A1:2014 Category P-II or P-III) are notrequired to meet the more onerous requirements for locomotive hauled coaches(Category P-I) or wagons (Category F-I).

G 2.6.6 Clause 4.1 of prEN 15227:2016 (BS EN 15227:2020 when published) includes thestatement that “It is recognized that operational requirements may require newcrashworthy and existing non-crashworthy vehicles to exist in the same train, but suchcombinations of vehicles are not required to comply with this European Standard.”

G 2.6.7 The same principles apply equally to translator vehicles for hauling existing stock builtto earlier standards or specifications and to include, for example, LondonUnderground or metro vehicles.

G 2.6.8 It is good practice to ensure that each coupling system on a barrier or ‘translator’vehicle is as a minimum mechanically fully compatible with the vehicles with which itis intended to couple, in order to avoid unnecessary operational restrictions.


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Part 3 Elements interfacing with passengers and traincrew

3.1 Missile protection

3.1.1 Roofs

3.1.1.1 Roofs over areas which are freely accessible to passengers, personnel or traincrewduring normal service shall withstand, without penetration, the impact of a 100 kgconcrete cube.

Rationale

G 3.1.1.2 This controls the risks of injuries to staff and passengers from accidental or deliberatedislodging of coping stones from masonry overbridges and reflects historical GBpractice.

Guidance

G 3.1.1.3 This requirement need not be applied to inter-vehicle gangways where passengers orstaff are more likely to pass through rather than stand for periods of time. It istherefore good practice to apply this requirement to wide open gangways.

G 3.1.1.4 GB practice is to use a concrete cube with an edge length of 0.36 m dropped from aheight of 3.0 m above the roof, so that a flat surface hits the roof. It is permissible touse a validated simulation alone to demonstrate compliance with this requirement.

G 3.1.1.5 GB practice is to assess possible impact by other potential missiles of similar mass, sothat reasonably consistent roof impact strength is maintained throughout the vehicle.

G 3.1.1.6 It is not unreasonable for some degree of penetration to occur; however, it is goodpractice to ensure that the missile or object does not penetrate to the extent that:

a) it is exposed to, or enters, the occupied vehicle interior; orb) the impact results in the detachment of interior components or debris inside

occupied areas.

G 3.1.1.7 Roof mounted equipment may be used to provide the impact resistance required.

3.1.2 Forward-facing surfaces

3.1.2.1 Forward-facing surfaces of vehicles occupied by people shall have an equivalentimpact resistance to that required for the vehicle cab windscreens as set out in clause6.2.6 of BS EN 15152:2019.

Rationale

G 3.1.2.2 This controls the risks of injuries to drivers from ballast and other debris that can bedislodged by passing trains and could otherwise penetrate the vehicle.

Guidance

G 3.1.2.3 The projectile set out in Annex A of BS EN 15152:2019 is the same as specified inUIC 651.



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G 3.1.2.4 It is permissible to use a validated simulation alone to demonstrate compliance withthis requirement.

3.2 Bodyside windows

3.2.1 Double-glazed units

3.2.1.1 Except where used in sleeper vehicles (see 3.2.2), double-glazed window units shall befitted with laminated glass on the inside and toughened glass on the outside of thevehicle.

3.2.1.2 Where double-glazed units are fitted, either:

a) A means of easily recognisable identification in English shall be provided on boththe interior and exterior of the window to distinguish between laminated ortoughened safety glass in order to show that windows are correctly fitted alongthe bodyside of the vehicle; or

b) The double-glazed unit and its mounting to the vehicle shall be designed toprevent incorrect installation.

Rationale

G 3.2.1.3 This requirement assists RUs in discharging their responsibilities under the Health andSafety at Work Act 1974 (HASAWA), as it controls hazards 3, 5 and 6 listed in clauseG.A.9.1.6 of GMRT2100 issue six. It reflects the findings of RSSB report T424 (2007).

G 3.2.1.4 Laminated glass retains a degree of structural integrity even when broken.

G 3.2.1.5 RSSB report T424 (2007) states that the use of laminated glass on the exterior is tobe discouraged as it can impede access into the vehicle for the emergency services(hazard 8 as listed in clause G.A.9.1.6 of GMRT2100 issue six).

Guidance

G 3.2.1.6 The definition of ‘bodyside windows’ includes windows in doors and cab side windowsin addition to the windows in passenger saloons, catering areas and toilets. Thisrequirement would not, for example, apply to bodyside windows to aid illumination ofa locomotive engine compartment or a freight wagon interior. See section A.9 ofGMRT2100 issue six.

G 3.2.1.7 For on-track machines, where there are cabs or operator areas that are unoccupiedoutside of possessions, the requirement for laminated safety glass does not need tobe applied.

G 3.2.1.8 For freight vehicles, where windows are required, toughened safety glass or someother suitable material may be used. In the case of hybrid vehicle types, such asfreight or parcels multiple units or driving van trailers, the requirement for laminatedsafety glass does not need to be applied to areas which are normally unoccupied bytraincrew or personnel.

G 3.2.1.9 For double-glazed units, where one pane is of toughened safety glass, therequirement for installing the toughened safety glass pane on the vehicle exteriorand the laminated safety glass pane on the interior is to ensure that:


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a) in the event of the outer toughened safety glass pane being broken due to impact,or in the course of access in an emergency, any passengers inside the vehicle arenot showered by glass fragments (hazards 6 and 8 listed in clause G3.4.16 ofGMRT2100 issue six);

b) the laminated safety glass interlayer is maintained within a temperature range atwhich its performance is optimal.

G 3.2.1.10 With the laminated safety glass pane on the inside, the interlayer temperature will beclose to the vehicle interior temperature and safely within the optimum range.

3.2.2 Sleeper vehicles

3.2.2.1 For dedicated sleeper vehicles, means shall be provided to allow compartment andcorridor windows to be safely removed or opened in an emergency to allowpassengers to escape from the vehicle.

Rationale

G 3.2.2.2 This requirement supports clauses 4.2.10.1 and 4.2.10.5.1 of the LOC & PAS TSI. Itcontrols the risks of passengers in sleeping compartments not being able to escape inan emergency and reflects GB historical practice.

Guidance

G 3.2.2.3 The layout of sleeping car vehicles often consists of a side corridor andcompartments, with small windows. In service, due to the internal layout, people arenot usually adjacent to the windows (either moving along the side corridor oroccupying a berth). In the event of a roll-over, occupants of a berth would findthemselves in a relatively confined space when compared to a conventional modernvehicle. As a result, their only credible means of escape could then be via the berthwindow or out from the berth and through the nearest side corridor window.

G 3.2.2.4 Toughened glass is therefore permitted to be retained for this type of vehicle.

G 3.2.2.5 Additional requirements for emergency exits are set out in BS EN 45545-4:2013.

3.2.3 Impact resistance for toughened glass bodyside windows

3.2.3.1 Where these are permitted, toughened glass bodyside windows shall be tested inaccordance with Appendix B.

Rationale

G 3.2.3.2 This requirement supports clause 4.2.2.9 of the LOC & PAS TSI. It controls the risk ofinjury to passengers from broken glass, and reflects GB practice for toughened glassin bodyside windows.

Guidance

G 3.2.3.3 The requirement for impact resistance is intended to protect against flying ballast orvandalism from outside the train. The weight of the missile and the impact speed



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selected are intended to represent the throwing of a large stone by a strong adultmale.

G 3.2.3.4 Allowance has been made, based on the test requirements in BS 857:1967, for whatcan reasonably be resisted by toughened glass. The higher value specified inGMRT2100 for laminated glass reflects the higher impact strength and betterprotection given by this material.

G 3.2.3.5 Further considerations for bodyside windows are set out in GMRT2100 issue six.

3.2.4 Emergency access

3.2.4.1 Testing shall be undertaken to demonstrate that the time to create an openingsuitable for access does not exceed 2 minutes, using tools typically available to rescueservices.

Rationale

G 3.2.4.2 This requirement supports clause 4.2.10.5 of the LOC & PAS TSI and controls the risksassociated with emergency services gaining access to the vehicle interior to rescuepassengers who are unable to evacuate themselves. It reflects GB practice assupported by RSSB Research Report T424 (2007).

Guidance

G 3.2.4.3 The specified access time has been established from tests conducted with the fire andrescue services. RSSB research reports T424 Phase 4 (2007) and T424 Phase 5 (2007)give guidance and descriptions of the tests undertaken.

G 3.2.4.4 Other requirements for bodyside windows are set out in GMRT2100 issue six.

3.3 External handrails

3.3.1 An external grab rail or handle shall withstand a perpendicular proof load of 1.7 kN,applied at any point along its length, without significant permanent deformation.

3.3.2 An external handle on an external door shall withstand a downward vertical proofload of 1.7 kN without significant permanent deformation.

Rationale

G 3.3.3 These requirements support the legal obligation to ensure safety of passengers andstaff (HASAWA). They control the hazards associated with passengers and staffentering and exiting vehicles and reflect GB historical practice.

Guidance

G 3.3.4 Requirements for passenger steps are defined BS EN 14752:2019.

G 3.3.5 Although the LOC & PAS TSI refers to EN 16116-1:2013, this relates specifically tosteps and grabrails for staff access and shunting staff, and the proof loads are lowerthan historically used in GB.


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G 3.3.6 External cab steps and grab rails, while normally exclusively intended for the use oftraincrew or personnel, are sometimes required to be used by passengers for thepurposes of evacuation.

G 3.3.7 For external handles which rotate, GB practice is to apply the proof load with thehandle in the worst-case position(s).

G 3.3.8 These load cases are established values used in GB, and ensure that thesecomponents do not bend significantly or break when a person is attempting to enteror exit a vehicle from a low level. In this situation it is possible for the full weight ofthe person, plus a dynamic increment, to be carried by the handle.

3.4 Gangways

3.4.1 A gangway shall withstand without significant permanent deformation the followingseparate proof loads:

a) A pressure load of 6 kPa on the standing floor area.b) A concentrated perpendicular load, acting from within the gangway, of 0.8 kN

applied over an area of 0.1 m × 0.1 m acting at any position on the surface of theside walls.

c) A differential pressure between the inside and outside of the gangway of ±2.5 kPa.

3.4.2 In the case of vehicles with a maximum speed above 200 km/h (125 mph), orpressure sealing, an appropriate quasi-static aerodynamic pressure load shall bedetermined according to the requirements set out in section 2.1.4 of GMRT2100 issuesix.

Rationale

G 3.4.3 These requirements support clause 4.2.2.3 of the LOC & PAS TSI. They control the riskof gangway structural failure and passenger injuries and reflect GB historical practice.

G 3.4.4 Clause 7.5.5 of BS EN 16286-1:2013 states “the aerodynamic loads shall be definedin the specification”. GB aerodynamic loading requirements are set out in section 2.1of GMRT2100 issue 6.

Guidance

G 3.4.5 The load cases are generally more onerous than given in BS EN 16286-1:2013, andrepresent respectively:

a) The maximum number of people that could theoretically be accommodated onthe gangway floor;

b) The effect of somebody falling or being projected against the gangway side. Thisis the same load case as for exterior doors in GMRT2100 issue six;

c) The maximum differential air pressure which would normally be expected inunsealed vehicles. This is the same load case as for exterior doors in section 3.2.1of GMRT2100 issue six.

G 3.4.6 For loading on the gangway floor, clause 7.5.2 of BS EN 16286-1 clause 7.5.2 refers toBS EN 15663, which would mean a load between 3.4 kPa and 6.8 kPa (based on thestanding passenger density of between 350 kg/m² and 700 kg/m²).



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G 3.4.7 The method of gangway mounting, and how the gangway behaves in the event of acollision, requires careful assessment to ensure that the gangway elements do notinterfere with coupler collapse, anti-climber engagement or structural crush zones. Itis therefore good practice to include assessment of gangway collapse in any overallcollision energy management strategy. See also clause 7.7 of BS EN 16286-1:2013.

3.5 Aerodynamic loads on passengers and traincrew

3.5.1 People inside railway vehicles shall not be subjected to pressure pulses of more than10 kPa:

a) When trains pass through tunnels;b) From aerodynamic interaction with other trains;c) From aerodynamic interaction with infrastructure features; ord) In the event of a sudden failure of the sealing of a pressure-sealed unit.

Rationale

G 3.5.2 This requirement is for technical compatibility with the GB mainline infrastructuresubsystem. It helps the railway undertaking to discharge its responsibilities under theHealth and Safety at Work Act 1974 (HASAWA) by controlling the hazards associatedwith the effects of pressure pulses on people’s health.

G 3.5.3 The 10 kPa value reflects GB historical practice.

Guidance

G 3.5.4 Established GB practice is to determine transient air pressure variations by testing,calculation, comparison with other vehicles, or by a combination of these.


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Part 4 Wheelskates

4.1 Vehicle compatibility

4.1.1 A rail vehicle shall be designed to allow the use of either an existing design ofwheelskate or a wheelskate designed specifically for that type of vehicle.

4.1.2 The vehicle design shall ensure the area around the wheelset is free from obstruction,or that all such equipment is easily removable, to enable fitment of either an existingdesign of wheelskate and appropriate packing pieces or for the fitment of awheelskate designed specifically for that type of vehicle.

Rationale

G 4.1.3 This requirement supports clause 4.2.2.6 of the LOC & PAS TSI. Use of a wheelskate isGB practice to enable the recovery of a rail vehicle with a seized or damaged wheelsetor transmission.

Guidance

G 4.1.4 Designing a vehicle to accommodate an existing wheelskate design will avoidpotential operational complications due to the location and availability of suitablespecial designs.

G 4.1.5 A rail vehicle wheel diameter not less than 686 mm and not greater than 1372 mmwill ensure compatibility with existing standard designs of wheelskate.

G 4.1.6 The space envelope requirements for a standard wheelskate are shown in Figure 1.



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Figure 1: Assembled space frame for wheelskates

4.2 Infrastructure compatibility

4.2.1 A wheelskate shall support a seized or damaged wheelset on its own independent setof wheels.

4.2.2 A wheelskate shall be designed to be compatible with the lower structure gauge overthe range of vehicle conditions (load, suspension settlement, wear) for the vehicle orthe range of vehicles for which the wheelskate is designed. Factors to be assessedinclude axle load, new and worn wheel diameters, space envelope limitations aroundthe wheelset and compatibility with track features such as raised checkrails.

4.2.3 Wheelskates shall be designed so that the flange of the wheel being carried is clear ofthe head of the rail, without creating an unnecessarily heavy load from the vehiclesuspension.


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4.2.4 Wheelskates shall be designed such that recovered vehicles remain within theirdesigned swept envelope, subject to the operational speed restrictions required.

4.2.5 The swept envelopes of wheelskates (excluding the area occupied by the wheels andany frame member adjacent to the wheels of the wheelskate) shall provide thefollowing clearances:

a) 75 mm vertically above the plane of the rails for a distance of 630 mm either sideof the centre line of the track, under all conditions, taking account of allsuspension movements and vertical curves; and

b) 7.5 mm, under worst case conditions, to the area reserved for items intended tocome in close proximity to trains (for example raised check rails, conductor railsand AWS magnets) forming part of the lower structure gauge.

Rationale

G 4.2.6 See G 4.1.3. The dimensions given have been shown to minimise the risk of contactbetween the wheelskate structure and typical track features.

Guidance

G 4.2.7 The use of skids is not permitted.

G 4.2.8 Keeping the flange of the wheel being carried above the head of the rail will facilitatetraversing of various track features. However, raising the wheel too high may stiffenup the primary suspension leading to higher dynamic loading.

G 4.2.9 Raised check rails may be encountered, particularly at obtuse crossings; these may beoutside of the normal structure gauge envelope. It is therefore good practice tochamfer the extremities of wheelskate side members or other parts to minimise theconsequences of contacting raised check rails.

G 4.2.10 Good practice for wheelskate design would include discussion between all affectedparties to agree suitable operational rules.

G 4.2.11 RIS-8270-RST requires railway undertakings and infrastructure managers to maintain,update and make freely available to relevant parties the available data that describesasset characteristics relevant to compatibility.

4.3 Wheeskate structures

4.3.1 A wheelskate shall withstand the simultaneous application of:

a) a vertical proof load of the maximum vertical static load multiplied by a factor of1.3 to take account of forces generated by canted track, switches and crossingsand track discontinuities; and

b) a lateral proof load, which shall be assumed to be a maximum of 0.3 of thevertical proof load.

4.3.2 A wheelskate shall have a survival probability under fatigue loading of at least 97.5%,calculated using the cumulative damage method, when subjected to:

a) a vertical fatigue load range, from zero to the vertical proof load, for 3.2 × 104

cycles; and



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b) a lateral fatigue load range, from zero to the lateral proof load, for 3.2 × 104

cycles.

4.3.3 As an alternative, it is permissible to develop fatigue load cases from experimental,simulation and calculation data.

4.3.4 Wheel and axle stresses shall be determined using a recognised and proven method.

4.3.5 Wheel materials shall be compatible with the requirements of RIS-2766-RST. Wherewheel steels are not available, it is permissible to use more generally availableengineering steels with equivalent mechanical properties.

4.3.6 Wheelskates shall use independently rotating wheels.

4.3.7 The design life of the bearings used in wheelskates shall be defined using arecognised and proven method including the following:

a) Radial and lateral loads;b) Additional load inputs due to predictable wheel-tread defects;c) The full range of operating duties, operating speed and loads; andd) Requirements for bearing lubrication.

4.3.8 Sealing shall be provided for the axle bearings to restrict ingress of foreign substancesand loss of lubricants.

Rationale

G 4.3.9 See G 4.1.3. These requirements represent GB practice for ensuring the structuralintegrity of the wheelskate design.

G 4.3.10 The use of independently rotating wheels avoids the generation of longitudinal wheelforces.

Guidance

G 4.3.11 No associated guidance.

4.4 Wheelskate wheel geometry

4.4.1 Wheels of wheelskates shall be manufactured and maintained to the P6 wheel profile.

4.4.2 The design minimum wheel-tread diameter shall be not less than 200 mm. Thescrapping limit of any wheel shall not be less than 187 mm. Tread diameter shall bemeasured at the tread datum.

4.4.3 The wheelskate design shall achieve a distance between the flange-backs across thewheels within the range 1360 mm to 1362 mm.

4.4.4 The width of the wheel rim measured between the flange-back and the outside faceof the rim shall be within the range 127 mm to 140 mm.

Rationale

G 4.4.5 See G 4.1.3. The P6 profile and the associated dimensions represent GB practice andhave been proven in service.


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Guidance

G 4.4.6 Terms and definitions associated with wheels are as set out in GMRT2466 andRIS-2766-RST.

G 4.4.7 The dimensions represent a compromise between accommodating the wheels of thevehicle being carried and the high contact stresses associated with small wheels.

4.5 Wheelskate operational limits

4.5.1 On running lines, the maximum speed of any vehicle fitted with a wheelskate shall belimited by the axle load as set out in Table 2.

Vehicle category Vehicle design axle load Maximum speed ofwheelskate

Vehicles with bogies of three ormore axles

Greater than 20 tonnes and lessthan or equal to 25.5 tonnes

32 km/h (20 mph)

Vehicles with bogies of three ormore axles

Up to 20 tonnes 40 km/h (25 mph)

All other vehicles Greater than 20 tonnes and lessthan or equal to 25.5 tonnes

40 km/h (25 mph)

All other vehicles Up to 20 tonnes 48 km/h (30 mph)

All vehicles fitted with wheelshaving a design diameter of lessthan 250 mm

Any weight 32 km/h (20 mph)

Table 2: Maximum speeds for vehicles fitted with wheelskates

4.5.2 Where the permissible speed through curves, switches and crossings is under normalconditions restricted to 50 km/h (30 mph) or less, or at any obtuse crossing, themaximum speed of any vehicle fitted with a wheelskate shall be limited to 5 km/h(3 mph, walking pace).

4.5.3 In yards and sidings, the maximum speed of any vehicle fitted with a wheelskate shallbe limited to 5 km/h (3 mph, walking pace).

Rationale

G 4.5.4 See G 4.1.3. These operational requirements represent established GB practice.

Guidance

G 4.5.5 None.



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Part 5 General design considerations

5.1 Primary and secondary elements

Guidance

G 5.1.1 The division between primary and secondary structural elements made in GMRT2100and RIS-2780-RST is, to some extent, arbitrary; it is acknowledged that for somevehicle designs the boundaries between the different sub-systems may be difficult todefine precisely. In addition, different sub-systems often interact, for example:

• bodyshell deflections can affect the performance of door systems;• mechanical door system loads will be reacted by the local bodyshell structure.

G 5.1.2 Good structural design will assess the overall structural integrity requirements for thevehicle as a complete system.

G 5.1.3 The intention of the mandatory requirements is to ensure that all structural elementsof a rail vehicle, primary and secondary, are designed to a common standard. It isintended that the secondary structural elements of vehicles are compatible withdynamic loadings that might be imposed due to a collision or derailment or suddenunexpected movement due to heavy braking or track irregularities.

G 5.1.4 Primary structures are those elements of a vehicle whose main purpose is towithstand or distribute the loadings seen in normal operation and in exceptionalcircumstances such as collisions or derailments. In general, primary structures are:

a) bodyshell (see BS EN 12663:2010+A1:2014);b) bogies (see BS EN 13749:2011 and clause 5.16);c) structural elements required for crashworthiness (see BS EN 15227:2008+A1:2010

or BS EN 15227:2020 when published, and sections 5.13 and 5.14 of thisdocument);

d) couplers and drawgear (see GMRT2100 issue six).e) equipment rafts and cases (see BS EN 12663-1:2010+A1:2014 and

sections 2.4 and 5.15 of this document);f) jacking and lifting features (see BS EN 12663:2010+A1:2014, BS EN 16404:2014

and section 5.12 of this document).

G 5.1.5 For the purpose of this document, secondary structural elements are those elementsof a vehicle which interface directly with passengers or traincrew. In general, theseare:

a) windscreens (see BS EN 15152:2019 and GMRT2100 issue six);b) windows (see section 3.2 of this document and GMRT2100 issue six);c) doors (see EN 14752:2015, EN 16116-1 and -2:2013 and GMRT2100 issue six);d) gangways (see EN 16286-1:2013 and section 3.4 of this document); ande) interiors, for example: seats, tables, panelling and partitions (see GMRT2100 issue

six).


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5.2 Material selection

Guidance

G 5.2.1 Vehicle structures have traditionally been fabricated from steel or aluminium alloys,using material grades that exhibit good levels of ductility (with elongation of typicallyup to 30% for mild steels and 6% for aluminium extrusions).

G 5.2.2 Aluminium castings using typical commercial alloys and casting techniques generallyexhibit low ductility (typically 5% or less).

G 5.2.3 The use of new or alternative materials or methods of construction is permissible,provided that the overall objectives of a safe vehicle design are achieved.

G 5.2.4 As there are many requirements for crashworthiness and localised impact resistance,it is good practice to assess the performance of any alternative materials to ensurethat satisfactory behaviour is achieved under extreme loading conditions. To achieveconsistent behaviour for structural elements designed to absorb energy, it is oftennecessary to use tighter tolerances on material properties than those given by thestandard specifications. The need or otherwise for applying additional controls can bedemonstrated by varying the properties in simulations or by suitable testing.

G 5.2.5 Other factors that may need to be assessed are as follows:

a) repair and disposal;b) behaviour under fatigue loading;c) the potential for degradation due to ageing or environmental factors such as:

i) temperature;ii) humidity;iii) sunlight; andiv) salt spray.

G 5.2.6 Failure is classed as a structural defect or defects, which render the vehicle no longersafe for normal operation. Failure can arise from overload, fatigue loading, corrosion,degradation or any combination of all of these.

5.3 Structural material properties

Guidance

G 5.3.1 GMGN2615 states the appropriate environmental temperature range for GB is T1(-25°C to +40°C) as defined in BS EN 50125-1:1999.

G 5.3.2 There is a risk of brittle fracture of some metals at very low temperatures. For typicalmetals used in rail vehicle structures, good practice is to select material grades with alow risk of brittle fracture at low temperature. Structural steels such as defined in theBS EN 10025 series can be impact tested at 0°C, -20°C or -40°C. The costs of testing at-40°C to ensure compliance with the -25°C requirement may not be economicallybeneficial compared to the frequency of occurrence of such low temperatures. This isreflected in the WAG TSI, clause 6.2.2.7.



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G 5.3.3 For other materials, both minimum and maximum temperatures may be significant interms of structural performance. This is likely to apply particularly to non-metallicmaterials.

G 5.3.4 Other than the general operational environment, local temperatures can be affectedby equipment operation (diesel engines, power electronics in confined spaces) orexternal effects (solar gain or wind chill). It is therefore good practice to assess theeffects of operational temperature conditions on the structural performance ofmaterials.

G 5.3.5 When selecting structural materials, it is good practice to ensure that the followinggeneral design objectives are met:

a) The structure will remain fully serviceable when subject to the maximum loadsimposed by exceptional circumstances, which are typically represented by theproof load cases set out in BS EN 12663-1:2010+A1:2014, BS EN 12663-2:2010and BS EN 13749:2011;

b) The structure will not fail as soon as the design load cases are exceeded; therewould always be an acceptable factor of safety, represented by the ultimate loadfactor, to account for uncertainties arising from calculation or testing, to cater forvariations due to manufacture, operation and maintenance, and to give areasonable margin for novel or unforeseen circumstances; and

c) The structure will have sufficient durability to withstand the operational loadingregime throughout the intended vehicle life. This is typically 30 - 35 years or, forsub-assemblies, the design life of the item where this is less than the design life ofthe vehicle.

Note: There is no technical reason preventing the vehicle or componentdesign service life being significantly shorter than 30 years; this is likely tobe driven by contractual and economic factors.


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5.4 Calculations and analysis

Guidance

G 5.4.1 GMRT2100 and associated standards assume that:

a) calculations are carried out to a high degree of accuracy by competent peoplewho are conversant with the methods to be used, whether finite element analysisor classical methods;

b) scatter in material properties is catered for by using the minimum or otherappropriate values. For crashworthiness where collapsible elements are required,maximum values may also need to be controlled; and

c) manufacture is well-controlled and carried out in a manner consistent with thedesign assumptions.

G 5.4.2 Good practice in calculations is to include allowances for the uncertainties associatedwith material properties and methods of calculation, manufacture and assembly.

G 5.4.3 For finite element calculations, hot-spots can be a function of the element type, therepresentation of the structural geometry, the characteristics of the element mesh(element density and shape) or methods used for applying or reacting loads or theboundary conditions.

G 5.4.4 In determining at a localised hot-spot what constitutes significant permanentdeformation, it is good practice to include assessment of:

a) the potential consequences of failure or rupture at that point;b) the extent to which, in immediately adjacent areas, there is enough strain energy

stored when loaded to effectively pull back any deformation when the load isremoved;

c) the extent to which any apparent stress concentration may be due tosimplifications inherent in the analysis model or due to the calculation methoditself.

In this case it is recommended that a more detailed local analysis is made of thedetail or a typical generic detail to clarify the stress pattern wherever possible.

G 5.4.5 Good practice is to eliminate stress hot-spots which are related to the method ofcalculation as far as possible, in order to focus attention on genuine stressconcentration effects. This can be achieved by refining or otherwise altering the meshto demonstrate that the results are independent of the mesh.

5.5 Bolted joints

Guidance

G 5.5.1 Bolts are often torqued to a high proportion of the bolt material yield stress, thereforea well-proportioned friction grip joint may not give a reserve factor of 1.15 based onthe bolt stresses. However, in terms of the load capacity of the joint, the reservefactor specified will be easily exceeded.

G 5.5.2 For a friction grip bolted joint, or similar connections, good practice is to calculate theproof reserve factor as the proof load capacity of the joint divided by the load



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applied, rather than directly using fastener stresses. In this case, it is good practice toincrease the applied load by the proof factor rather than reducing the allowablestress.

G 5.5.3 A new European standard is being developed for the design of bolted joints on railvehicles. Until this is available, use of VDI 2230 or other similar procedures may beappropriate.

5.6 Bonded joints

Guidance

G 5.6.1 Structural adhesive bonding techniques and other processes may make it difficult orimpossible to examine completed joints non-destructively.

G 5.6.2 Where these are used, it is good practice to put procedures in place to ensure that allprocesses are correctly and consistently applied, for example: surface preparation,curing time and associated environmental conditions.

5.7 Effect of glazing

Guidance

G 5.7.1 Glazing is not usually regarded as a structural element; GB practice is therefore toexclude it from bodyshell structural analyses. However, if the mounting arrangementsor bonding methods are sufficiently understood and controlled, it could be possible toinclude the strength and stiffness of the glass panes in an overall structuralassessment and thereby achieve a lighter or simpler structure. This would be anacceptable approach in terms of service or fatigue loadings, but, under proof andultimate load conditions, it is essential that any breakage of the glass elements wouldnot jeopardise the integrity of the structure.

5.8 Vehicle categories

Guidance

G 5.8.1 The structural categories according to BS EN 12663-1:2010+A1:2014,BS EN 12663-2:2010 and BS EN 15227:2008+A1:2010 (or BS EN 15227:2020 whenpublished) will be determined from an assessment of the intended use and theoperational environment. It is good practice to select the most appropriate categoryto achieve a safe, economic and lightweight vehicle design.

G 5.8.2 Category P-I is appropriate for loco-hauled coaching stock which is likely to befrequently shunted into different formations; this is generally not the case for mostGB mainline coaches, particularly those fitted with semi-permanent intermediatecouplers. The majority of GB mainline passenger rolling stock is therefore expected tofall into category P-II but possibly, in some circumstances, categories P-I or P-III.

G 5.8.3 Passenger vehicles may be designed to category P-III (or P-IV, P-V) for specific routesor services in order to realise benefits in reduced mass, initial and operational costs. In


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this case, it will need to be demonstrated that operation is acceptable as part of theroute compatibility assessment process as set out in RIS-8270-RST.

G 5.8.4 Freight vehicles are usually designed to category F-II for GB operation.

G 5.8.5 The appropriate crashworthiness design category for GB mainline locomotives andpassenger vehicles is likely to be C-I, as there are very few routes where there are nolevel crossings. C-III is appropriate for tram-trains.

G 5.8.6 Less onerous structural categories, such as P-III and C-II may be justified where:

a) service operation is on secondary routes which are completely or predominantlyisolated from the general network (and no level crossings for C-II); and/or

b) there are additional signalling or control measures in effect; and/orc) the pattern of traffic is such that the risk of vehicles designed to different

requirements being operated on the same route at the same times is very small.

G 5.8.7 Refer to Annex A of BS EN 15227:2008+A1:2010 (or BS EN 15227:2020 whenpublished) for guidance on the collision scenarios and their applicability.

G 5.8.8 In some instances, it is possible to categorise a vehicle as either passenger or freight.It is good practice to ensure each vehicle is structurally compatible with the rest ofthe train design. For example, a driving trailer or vehicle dedicated to carryingbaggage or parcels, without passenger accommodation, but with a full gangwayconnection at one or both ends to the remainder of the train, would be expected tobe categorised as a passenger vehicle.

5.9 Freight vehicles

Guidance

G 5.9.1 New designs of freight vehicle are required to comply with the WAG TSI; this calls upBS EN 12663-2:2010 and BS EN 12663-1:2010+A1:2014 for structural design of thevehicle body and BS EN 13749:2011 for bogies. GB practice is to useBS EN 12663-1:2010+A1:2014 together with part 7 of BS EN 12663-2:2010; see also G 2.1.6.

G 5.9.2 New freight vehicles for the carriage of dangerous goods are also required to complywith the Regulations concerning the International Carriage of Dangerous Goods byRail (RID). GB specific requirements for tank wagons for dangerous goods are set outin GMRT2100 issue six.

G 5.9.3 Further guidance on freight vehicle design is contained within GMGN2688.

5.10 Passengers and payload

Guidance

G 5.10.1 The operational payloads given in BS EN 15663:2017+A1:2018 vary according tovehicle category and represent the maximum loadings expected to be seen on aregular basis (for example once or twice per day). The resulting payload for a vehicledoes not necessarily represent either an average value or the load condition thatwould be used for fatigue design.



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G 5.10.2 In determining maximum passenger loadings, it is good practice to include carefulassessment of the passenger density corresponding to a credible worst-case crushloading. This would ensure that while a safe and conservative design is achieved, thevehicle structure is not over-specified with potentially adverse consequences in termsof weight and manufacturing cost.

G 5.10.3 It is recognised that the standard design load cases may not necessarily representreal conditions for a given vehicle. However, when taken collectively, they constitute aseries of performance limits which have evolved over time. These collectively define aboundary between acceptable and unacceptable structural performance under realconditions which cannot always be accurately described. It is good practice toaccount for this when developing customised load cases based on actual serviceconditions.

G 5.10.4 When developing replacement or supplementary load cases, it is good practice todetermine:

a) whether the structures have significantly different characteristics to previousgenerations of vehicles from which existing load cases have been evolved;

b) whether any other underlying assumptions have changed;c) whether operational practices have changed;d) for a particular application, whether the generalised load case requirements are

suitable or if a more sophisticated approach would yield benefits in terms ofreduced mass or lower costs;

e) for rolling stock designed to more customised requirements, the interaction withother rolling stock and the infrastructure;

f) if alternative or additional load cases are required to correctly represent serviceconditions, it is good practice to express them as functions of the reference massstates as set out in BS EN 15663:2017+A1:2018.

G 5.10.5 For commuter vehicles it is likely that at least two states of fatigue loading would beassessed; representing respectively peak hour conditions and the rest of the day. Inaddition to these operational loadings, essentially when the vehicle is moving, thefatigue damage due to loading and unloading cycles can also be significant. A similarsituation applies to freight vehicles, where significant mileages could be operatedwhen empty.

G 5.10.6 For passenger vehicles, BS EN 15663:2017+A1:2018 specifies a mass per squaremetre (kg/m²) rather than specifying a number of passengers per square metre as inprevious GB specifications. Any increase in the average individual passenger mass willbe compensated for by the assumption that, since physical size will also increase,passenger density will necessarily decrease.

5.11 Static and fatigue loading

Guidance

G 5.11.1 Most of the vertical and longitudinal load cases given inBS EN 12663-1:2010+A1:2014 or BS EN 12663-2:2010 are equivalent to thosecontained in historical standards (such as UIC leaflets, earlier versions of GroupStandards and British Rail Load Case Documents).


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G 5.11.2 Where reference is made to coupler height or buffer height, the specified proof loadsare intended to be applied at the positions where these items are fitted to the vehiclestructure. For example, a passenger multiple unit, designed to comply with CategoryC-I of BS EN 15227:2008+A1:2010 (or BS EN 15227:2020 when published), is likely tobe fitted with energy-absorbing devices where there would otherwise be buffers. Inthis case, the buffer loading set out in Table 2 of BS EN 12663:2010+A1:2014 wouldbe applied to the energy-absorber mounting points on the vehicle. The physicalcharacteristics of the couplers, buffers or anti-climbers do not form part of thestructural requirements for the primary vehicle structure.

G 5.11.3 The structural load case requirements are applicable to a very wide range of vehicletypes and operational conditions. There is a degree of flexibility possible in theprecise interpretation of the requirements, which caters for different types and stylesof construction. As a result, several outcomes are possible.

G 5.11.4 It is good practice to agree the applicable set of detailed loadings and parameters tobe assessed at the earliest possible stage of design. This will ensure that:

a) any perceived commercial risk or uncertainty concerning design scrutiny andapproval is minimised; and

b) an unnecessarily conservative design with attendant cost and weight penalties isavoided.

5.12 Lifting and jacking

Guidance

G 5.12.1 Requirements for lifting for maintenance and recovery purposes are given in clause4.2.2.6 of the LOC & PAS TSI, BS EN 12663-1:2010+A1:2014, BS EN 12663-2:2010and BS EN 16404:2014.

G 5.12.2 As indicated in the introduction to BS EN 16404:2014, recovery operations may placeadditional loads on a vehicle structure, particularly after severe collisions or accidentswhere vehicles may have rolled, overturned or have been significantly displaced orpitched vertically. These loads are difficult to anticipate but, if not considered, couldresult in significant permanent deformation or failure and therefore place recoverystaff at risk.

G 5.12.3 It is therefore good practice to determine limits for additional transverse, vertical andlongitudinal forces on lifting and jacking points, related to weight transfer due tovehicle attitudes such as roll or pitch, with appropriate guidance included ininstructions for re-railing and recovery. It is established GB practice to ensure that alifting and jacking point can withstand, as proof loads at least:

a) a lateral load of ±25% of the nominal vertical force; andb) a longitudinal load of 5% of the nominal vertical force.

These values are intended to represent typical vehicle attitudes following minorderailments. They are consistent with the design scenarios for rerailing given in BSEN 16404 (For scenario 2, 5% is equivalent to 350 mm over a 7 m wheelbase(such as a 4-wheel wagon), and 25% lateral load is equivalent to 15° inclination



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for scenario 3). BS EN 12663-1:2010+A1:2014 requires a lateral force for lifting of15% of the vertical force.

G 5.12.4 During a rail vehicle’s life a significant number of vehicle lifts will be required formaintenance and repair, whereas many vehicles will never require to be recoveredafter a derailment or collision. When designing the arrangements for lifting andjacking, it is good practice to consider the ease with which vehicles can be preparedand then lifted on a routine basis as well as for the purposes of re-railing and recoveryshould be considered. From a maintenance perspective, it is good practice to considerthe implications for subsequent access to vehicle equipment.

G 5.12.5 In addition, where other parts of a vehicle structure could see significant loads due torecovery, for example bodysides, it is good practice to consider other limitingconditions.

G 5.12.6 Where lightweight or novel forms of construction are used in a vehicle’s primarystructure, it is good practice to consider the potential consequences of a safe andotherwise satisfactory recovery operation, in terms of how the recovery might affect avehicle’s subsequent repair and return to traffic. For example, thin-walled extrusionshave an inherent potential for localised crushing, which may be very difficult to returnto a satisfactory condition.

G 5.12.7 Where damage during recovery could be a significant issue, it is good practice toconsider the placement of additional emergency lifting points where suitable features(for example lugs or tapped holes for eyebolts) could be located without materiallyincreasing weight or unduly increasing the complexity of the vehicle structure.

G 5.12.8 Under some circumstances, vehicles may need to be dragged or winched as part of arecovery operation, using ropes or cables. These may be attached to vehicle couplingseither directly or making use of an adaptor coupling. Where there could be the risk ofdetachment or damage, it is good practice to consider the provision of suitablealternative attachment points on the end structure of the vehicle.

G 5.12.9 GB practice has been to include safety factors higher than those specified in BS EN16404:2014. An effective safety factor of 4 was applied for the ultimate load case forlifting (2 g acceleration with a factor of 2). Using BS EN 12663 implies a total factorfor the ultimate load of approximately 2.5, from the combination of 1.1 (g –acceleration from table 10) × 1.5 (ultimate factor from clause 5.4.3) × 1.5 (additionallocal safety factor). However, this does not consider either:

a) the 10 mm displacement / unloading specified in clause 6.3.3 ofBS EN 12663-1:2010+A1:2014; or

b) the 100 mm displacement / unloading specified in BS EN 16404:2014.

Accounting for these effects is considered equivalent to applying an overallultimate load factor of 4.

G 5.12.10 GB standards have also specified a jacking pad geometry of not less than22,400 mm² (effectively 150 mm × 150 mm). While an equivalent is specified inBS EN 16404:2014 for bogie support points (clause 5.1.9), the requirement elsewhereon the vehicle is for jacking pad surfaces to be of at least 10,000 mm² (effectively100 mm × 100 mm). While this could be seen as more than doubling the stress for thesame lifting or jacking load, the stress will be heavily influenced by the contact area


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with the jack itself. Further, it is common practice to use packing between the jackand the jacking pad. Therefore, in practice, there is unlikely to be any issue providedthe other specified requirements are met.

5.13 Collision loads

Guidance

G 5.13.1 The collision scenarios in prEN 15227:2018 (BS EN 15227:2020 when published)require the complete train to be assessed as a system. It is therefore good practice todevelop a complete collision energy management strategy such that, in addition tothe characteristics of the primary structure and any structural collapse zones within it,the characteristics of couplers, drawgear and anti-climbers are also assessed.

G 5.13.2 For fixed formation units, an effective collision energy management strategy has thepotential to maximise useable space that could be otherwise lost, and to minimiseany possible weight penalties that might be incurred, by allowing the designer totailor or adjust collapse zones according to a vehicle’s position within the train.BS EN 15227:2008+A1:2010 (and BS EN 15227:2020 when published) sets outdetails of reference trains to be used for variable or non-fixed formations, for examplefreight trains and traditional locomotive hauled passenger trains.

G 5.13.3 BS EN 15227:2008+A1:2010 (and BS EN 15227:2020 when published) sets outperformance requirements for prevention of overriding in the event of a collision.These form part of the collision energy management strategy and, beingperformance based, give design flexibility. Assessment of weight and potential repaircosts would normally be part of the contract between the vehicle purchaser and themanufacturer; but these might determine the method of achieving the requiredperformance, for example:

a) separate bolted-on energy absorbing anti-climber units; orb) fixed devices at the ends of individual vehicles; orc) limits on coupler movements.

G 5.13.4 At the intermediate ends within a fixed formation rake, the required functionalitymay be incorporated into the coupler assemblies instead of using toothed plates.Where the coupler assembly is used, it is good practice to assess the ability to controlrelative roll between vehicles by this method.

G 5.13.5 Although the collision scenarios apply principally to straight track, it is good practicealso to assess performance on curves.

G 5.13.6 Currently there is no accepted standard position or contact geometry or profile foranti-climber location in GB or Europe. It is therefore good practice to assesscompatibility with other vehicles on the routes to be operated, such as:

a) existing rolling stock designs that are likely to be encountered; andb) the likelihood of accidentally contacting vehicles fitted with conventional buffers.

G 5.13.7 It is good practice to ensure that the characteristics of couplers, buffers or anti-climbers are determined in conjunction with their required function and the overallcollision energy management strategy. For the purposes of calculation or test,



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relevant parts of these items or the equivalent may be included in order to correctlyrepresent any local stiffening or reinforcement that may be gained.

G 5.13.8 A degree of protection against overriding for buffered vehicles could be offered byusing retractable or shear-out buffers in conjunction with conventional anti-climberdevices or with an anti-climbing fender mounted immediately above the buffers.

G 5.13.9 In the case of shear-out coupler designs, it is good practice to determine where theeffective boundary between the coupler and the structure lies. Note that the primarypurpose of the coupler proof load case is to determine the strength of the completeprimary structure in compression and bending, and the local strength of theunderframe headstocks; these loads will not necessarily be applied to the coupler ordrawgear itself. The coupler and drawgear characteristics will be an outcome of theoverall collision energy management strategy.

G 5.13.10 Where doorways or vestibules are placed in or adjacent to structural collapse zones, itis good practice to assess very carefully the effects of controlled structural collapseduring a collision against the needs for access and evacuation afterwards, which maybe compromised if some vehicle exits are rendered partially or completely unusable.

G 5.13.11 Historical GB standards required the strengthening of vehicle ends to resistpenetration by objects which could be struck in a collision, for example: another railvehicle, road vehicles or lineside structures. These proof load requirements wereessentially to ensure that intermediate and non-driving vehicle end walls, end walledges and the edges of all door and window apertures were strengthened in additionto the standard longitudinal proof loads at floor, waist and cantrail heights.

G 5.13.12 These objectives are addressed through the requirements ofBS EN 15227:2008+A1:2010 (and BS EN 15227:2020 when published) for thepreservation of survival space for passengers and traincrew in the event of a collision.Vehicles designed using the collision scenarios set out in BS EN 15227:2008+A1:2020(and BS EN 15227:2020 when published) will provide an equivalent or higher level ofprotection than that required by historical GB standards. Note, however, that thespecified collision scenarios are not necessarily what will occur in a real accident. Forexample, vehicles may jack-knife in a derailment, causing adjacent vehicle corners tocontact each other. It is therefore good practice to assess the consequences of anysuch contact in the overall design of the vehicle.

G 5.13.13 Most GB passenger vehicles have end tapers for gauge clearance, to reduce overthrowon curves. The end wall needs to be as wide as possible to maximise protection for themain vehicle section by reducing to a minimum any ‘step’ in terms of primarystructural strength that could be caused by the vehicle body end taper. For example,this could be significant where a fibre reinforced polymer moulding is used to achievethe change in vehicle cross-section.

G 5.13.14 Good design practice where body end tapers are required, is to ensure that either:

a) the tapered portion of the vehicle structure side wall will transfer end wall loadingsinto the main structure without significant permanent deformation; or

b) the full section side wall edges are strengthened to withstand, without significantpermanent deformation, a body end wall edge load directly at the position wherethe body end taper begins.


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5.14 Obstacle deflectors

Guidance

G 5.14.1 Clause 4.2.2.5 (9) of the LOC & PAS TSI requires the fitment of obstacle deflectors to"the leading ends of locomotives, power cars, driving coaches and trainsets".Requirements for obstacle deflectors are set out in BS EN 15227:2008+A1:2010 (andBS EN 15227:2020 when published).

G 5.14.2 Many designs of obstacle deflector have blades that are hinged at the top edge; thisguarantees that as the blade deflects, the lower edges move away from the rail head.It is also acceptable for a complete deflector blade to deflect longitudinally, but it isessential that striking an obstacle will not permanently reduce the effective gap torail.

G 5.14.3 If there is likely to be appreciable rotation of the vehicle end under impact conditionsdue to a combination of the vehicle pitching on its suspension and deflection of thebody structure, it is good practice to assess the resulting blade angle when thedeflector is at its design load together with the rotation or displacement of thedeflector blade. It could therefore be desirable under some circumstances to inclinethe blade to some extent to ensure that it is reasonably vertical when fully loaded,thus minimise any potential for the vehicle to ride up over an obstacle.

G 5.14.4 Historical GB standards did not mandate the fitment of obstacle deflectors on routesequipped with third rail electrification; it was thought that the lineside fencing wouldmitigate against livestock wandering onto the track. The LOC & PAS TSI andBS EN 15227:2008+A1:2010 (and BS EN 15227:2020 when published) make no suchdistinction; the recent incident at Godmersham (RAIB report 05/2016) recommendsretro-fitment of obstacle deflectors where practicable.

G 5.14.5 GB requirements for obstacle deflectors were first established after the accident atPolmont (30 July 1984), when an Inter-City push-pull train was derailed after thedriving trailer hit a cow on the track at high speed.

G 5.14.6 Historical GB standards required, for operational speeds greater than 160 km/h(100 mph), that the axleloads of the leading bogie of the leading vehicle were atleast 120 kN to reduce the risk of derailment in the event of an impact. While aleading bogie axleload is not required by BS EN 12663-1:2010+A1:2014 orBS EN 15227:2008+A1:2010 (BS EN 15227:2020 when published), application of thespecified collision scenarios will give an equivalent overall resistance to derailment inthe event of a collision.

5.15 Body-mounted equipment

Guidance

G 5.15.1 The expressions set out in BS EN 12663-1:2010+A1:2014 and BS EN 12663-2:2010for vertical acceleration are intended to account for the effects of vehicle bounce andpitch: Fz = (1 ± c) × g , where c = 2 at the vehicle end, falling linearly to 0.5 at thevehicle centre. The corresponding proof acceleration values that were set out inhistorical GB standards were essentially the same, except that no adjustment wasmade for equipment placed at intermediate positions between the vehicle ends; a



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worst-case value was used. Using Fz = (1 ± 2) × g will simplify calculation and ensurethat equipment security is independent of its longitudinal position on the vehicle; auseful condition in the event that equipment needs to be relocated during vehiclerefurbishment.

G 5.15.2 To enhance the retention of equipment attached to vehicle bodies under overloadconditions, it is good practice to manufacture mountings and brackets from materialsexhibiting high levels of ductility.

G 5.15.3 Assessment of the load requirements for vehicle mounted equipment may be madeseparately from loadings required for specific items, such as, for example, seats,tables and grab rails. Where it can be shown that the combination of the generallyapplicable vehicle mounted equipment loadings and particular load requirementsresult in multiple loadings of essentially the same type but of different magnitudes, itmay not be necessary to undertake a formal assessment of the lesser loadings.

G 5.15.4 GB standards historically required a longitudinal acceleration of 5 g , reduced to 3 gfor rigidly connected fixed formation rakes. BS EN 12663-1:2010+A1:2014 requires alongitudinal proof acceleration of 3 g for category P-II passenger vehicles. Thisapparent reduction is however mitigated by the requirements of section 6.4 ofBS EN 15227:2008+A1:2020 (and BS EN 15227:2020 when published) which relatethe ultimate strength of equipment attachments to the collision scenarios specified.

G 5.15.5 Historical GB standards required the worst-case combination of equipment proof loadaccelerations to be analysed. BS EN 12663-1:2010+A1:2014 andBS EN 12663-2:2010 require the equipment acceleration loads to be analysedseparately. The difference between these approaches is not significant due to thedominant effect of the longitudinal acceleration. However, the effects of loadcombination may need to be assessed where:

a) a combination of loadings is likely to occur in the event of a collision; orb) the consequences of failure for the mounting arrangement would be severe.

5.15.1 Vibrations

Guidance

G 5.15.1.1 Clauses 6.5.2, 6.7.3 and 6.9 of BS EN 12663:2010+A1:2014 require assessment ofloads from equipment operation and vibration.

G 5.15.1.2 Self-exciting, resiliently mounted items such as engines or compressors mayconstitute a substantial mass mounted on a vehicle underframe at only three or fourpoints; these can adversely affect the bodyshell structure. For some loadingconditions, the inertia load cases specified may be insignificant compared to thosegenerated by the engine, compressor or other self-exciting equipment.

G 5.15.1.3 It is therefore good practice to assess locally generated accelerations, forces andresonances acting within and on equipment, as well as the specified proof andfatigue inertia loads.

G 5.15.1.4 On vehicles equipped with internal combustion engines, such as diesel multiple units(DMUs) or locomotives, engine-mounted components can be subject to accelerations


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and cycles which are significantly in excess of the normal load cases for bodymounted equipment.

G 5.15.1.5 For example, a recent investigation of an underfloor DMU engine installationidentified:

a) a peak vertical acceleration of 15 g , compared with the normal quasi-static proofload of 3 g ; and

b) more than 109 fatigue cycles over the required lifetime, compared with thestandard fatigue curve cut-off at 107 cycles.

G 5.15.1.6 Good practice would therefore ensure that:

a) robust estimates of both peak forces and force-load cycles due to locallygenerated accelerations, forces and resonances are obtained from calculation,testing or a combination of these, including normal operating force cycles andequipment vibration levels;

b) when items are resiliently mounted, adequate clearances are provided for typicalservice conditions, or that suitable bump stops are installed to prevent damagewhen overloaded by, for example, a heavy shunt;

c) the design of mounting brackets includes the assessment of potentially significantbending moments on equipment, for example: engine flywheel housings,crankcases or timing gear cases.

5.16 General considerations for bogies

Guidance

G 5.16.1 Load cases for bogies are defined in BS EN 13749:2011 as referenced in theLOC & PAS TSI and the WAG TSI; these are for “conventional” bogie and suspensiondesigns and include requirements for equipment attached to bogie frames andaxleboxes. Most of these are equivalent to load cases given in historical GB and otherstandards (such as UIC leaflets).

G 5.16.2 The load cases contained within Annexes B, C and D of BS EN 13749:2011 are givenas informative examples; they are aimed principally at testing rather than calculationor simulation. Section C.1 of BS EN 13749:2011 states “In reality the loads arecombined in a complex manner and so it is difficult to represent them exactly inanalysis”. The EN therefore puts the onus on the technical specification for the bogieto define key criteria such as the load cases, operating conditions and service life. Seealso BS EN 15827:2011.

G 5.16.3 Loads applied to the bogie are affected by track design and maintenance, includingtrack faults. Infrastructure installation and maintenance documents contain detailsof track maintenance limits and track fault conditions that can be encountered. ForGB mainline vehicles, in most cases, these will be Network Rail’s standards.

G 5.16.4 Good practice for four-wheeled vehicles, or where conventional bogies or suspensionsare not employed, would be to apply the relevant load cases in the immediate vicinityof attachments to the vehicle body, for a sufficient distance that suspension loadscan be adequately transferred into the primary vehicle structure.



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G 5.16.5 Load cases for body to bogie attachments are defined in BS EN 12663:2010+A1:2014and BS EN 12663-2:2010. These load cases are intended to ensure that bogies will, asfar as is practicable, stay attached to the body in the event of a derailment, collisionand during lifting or jacking for recovery.

G 5.16.6 Bogie retention is beneficial because:

a) the risk of additional injury or damage due to impacts with detached bogies isreduced; and

b) the drag or resistance to motion of a derailed train is generally significantly higherif the bogies remain attached, and thus a higher proportion of a train’s kineticenergy will be dissipated by this means rather than through structural collapse.

G 5.16.7 Analysis of accident data suggests a strong correlation between bogie retention andlower levels of passenger injury. Recent accidents have indicated that where vehicleshave been designed to recent GB standards, bogie retention has been generallysatisfactory even for severe derailments. This represents an improvement over earliergenerations of vehicles designed to lesser requirements.

G 5.16.8 For the body to bogie attachments, the longitudinal load is intended to represent theeffect of a heavy shunt or minor end-on collision.

G 5.16.9 Good practice is to ensure that when the ultimate loadings are exceeded, failure ofthe body to bogie connection will take place in a pre-determined manner and that asa result the primary vehicle structure will not suffer damage that could compromiseits integrity and thus expose passenger or traincrew to additional risk of injury.

G 5.16.10 A degree of additional bogie retention capability will be provided by parts of thesuspension such as roll-bars and yaw dampers even if this function is not explicitlypart of their design. Taking advantage of these connections, the overall bogieretention capability of a vehicle can be enhanced.

G 5.16.11 Where multiple connections are used as part of a retention arrangement, a gooddesign will, as far as possible, take into account the possibility of successive overloadof individual connections in the course of a derailment.

G 5.16.12 RSSB research report T088 (2004) established ‘worst-case’ design parameters toallow common equipment to be specified for application to a wide variety of vehicletypes. This included a very broad range of possible operating and track conditions,including degraded suspension modes and wheelset damage. These values maytherefore not be appropriate for generic load cases from the perspective of a vehicle.


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Appendices

Appendix A Derivation of load cases

A.1 Introduction

Guidance

G A.1.1 This appendix supports BS EN 12663-1:2010+A1:2014 and BS EN 12663-2:2010 bydetailing GB practice for the derivation of load cases from test or service data, and assuch is informative. It sets out the principal requirements for experimentaldetermination of load cases.

G A.1.2 The extent of testing and the degree of analysis will be dependent on the particularcomponent or components and the application.

G A.1.3 Where simulation is used to determine design loads, it is good practice to:

a) validate the models by comparison with available test or service data; andb) apply an additional safety factor commensurate with the extent of the validation

that can be achieved (see clause 5.3.2 of BS EN 12663-1:2010+A1:2014).

G A.1.4 It is good practice to ensure that any limitations regarding operation form part of theroute compatibility acceptance process as set out in RIS-8270-RST.

A.2 Data collection and processing

A.2.1 Data collection methods, sample sizes and processing methods employed shall befully documented.

A.2.2 Due account shall be taken of all potential sources of error and limitations due tosample size.

A.2.3 Calculation methods and models shall be validated against experimental data andservice experience where applicable.

Rationale

G A.2.4 These requirements support clause 4.2.2.4 of the LOC & PAS TSI and clause 4.2.2.2 ofthe WAG TSI. They control the risk of vehicle structural integrity being compromisedby use of unsubstantiated data and represent GB practice. See clauses 5.3.2 and6.6.4(b) of BS EN 12663-1:2010+A1:2014.

Guidance

G A.2.5 It is permissible for data derived from calculation or simulations to be used where testor service data is not available.

G A.2.6 It is permissible for historical load case data to be used where it can be demonstratedthat this is applicable and that satisfactory service performance has been achieved.



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A.3 Derivation of load cases

A.3.1 Derivation of load cases, from load cases used satisfactorily in past applications orfrom test data, shall include, as a minimum, assessment of the following factors:

a) Suspension configuration.b) Variability of suspension components due to manufacture, wear, localised failure

or degradation.c) Vehicle load due to passengers or payload.d) Vehicle speeds.e) Magnitudes and frequencies of traction and braking loads.f) Infrastructure on which the vehicle is to be operated.g) Variability of infrastructure due to maintenance and renewal cycles.h) Anticipated frequency of operation throughout the vehicle’s life.

Rationale

G A.3.2 See G.A.2.4.

Guidance

G A.3.3 See G A.1.2 and G A.1.3.

A.4 Application and limitations of derived load cases

A.4.1 Where fatigue load cases are determined from test data any potential limitations tothe operation of the vehicle in terms of design life shall be clearly identified.

A.4.2 For fatigue load cases derived from test data, it shall be determined if there are anyparticular combinations of load that act in phase.

Rationale

G A.4.3 See G.A.2.4.

Guidance

G A.4.4 Where it can be demonstrated that particular loads do not act in phase, these can betreated as if acting separately and the damage from the individual cases summed.


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Appendix B Bodyside windows - small missile test procedure fortoughened glass

B.1 Introduction

Guidance

G B.1.1 GB practice, as permitted by clause 7.5.2.1 of the LOC & PAS TSI, is to use oflaminated glass for all glazing in passenger vehicles, except for:

a) the outer pane of double-glazed windows; andb) sleeper vehicles.

G B.1.2 Toughened glass is also permitted for use in OTMs and freight vehicles

B.2 Conditions of test

B.2.1 To demonstrate that window glass has an acceptable level of resistance to impact bysmall missiles, across a representative temperature range, three successive complianttests at high temperature and three successive compliant tests at low temperatureshall be completed.

B.3 Test windows

B.3.1 The window units tested shall be an actual window or glazing system, which is to beinstalled in the vehicle, or of samples having minimum dimensions of1100 mm × 900 mm constructed in a manner representing their installed condition.

B.3.2 The window units or samples shall be tested with both panes installed in a mannerrepresenting their installed condition.

B.3.3 If samples are to be tested, they shall be mounted for testing in a mannerrepresentative of the installed condition for the complete unit.

B.3.4 The geometric centre of the window unit or sample shall be determined beforetesting. In the case of window units which are sub-divided by glazing bars, use a worstcase position or positions for the effective geometric centre.

B.4 Temperature

B.4.1 For the high temperature tests:

a) The window units or samples for testing shall be heat soaked at a minimum of35°C for a minimum period of 6 hours immediately preceding the test.

b) Under no circumstances shall the temperature of the inner surface of this pane ofglass be lower than 35°C at the time of the test.

B.4.2 For the low temperature tests:

a) The window units or samples for testing shall be heat soaked at a maximum of-17°C for a minimum period of 6 hours immediately preceding the test.

b) The temperature of the test specimen, when installed in the test apparatus, shallbe allowed to increase to give a nominal temperature of 0°C of the inner surface.



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c) Under no circumstances shall the temperature of the inner surface of the unit behigher than 0°C at the time of the test.

Guidance

G B.4.3 For windows with single panes only, it is acceptable for the inner and outer surfaces tobe at the same temperature; any variation of temperature through the panethickness can be discounted.

B.5 Impact test

B.5.1 The impacting object used for these tests shall be a solid steel ball of a mass of0.25 kg.

B.5.2 For testing toughened glass or toughened double glazed window units the steel ballshall be travelling at a speed of (50 ±3) km/h at the point of impact.

B.5.3 The window units or samples tested shall be orientated such that the ball impacts thegeometric centre of the unit.

B.5.4 The window units or samples shall be tested in such a way that the impacting objectfirst strikes the sample perpendicular to the surface representing the outside of thevehicle.

B.5.5 The total amount of spall from the inner surface of the window shall not exceed 40 g.

B.6 Penetration

B.6.1 The steel ball shall not fully penetrate the window units or samples under the highand low temperature tests.

B.6.2 No part of the ball shall be exposed to the area representing the interior of the vehicleduring the test.

B.7 Integrity

B.7.1 In the case of double glazed window units, there shall be no loss of structural integrityin the bonding between the inner and outer panes and spacer bars or any other fixingsystem between the window unit elements.


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Definitions

adaptor coupling A type of coupler which enables vehicles with incompatiblecouplers to be connected together for the purposes of rescueand/or transfer.

barrier vehicle A vehicle intended to separate or segregate other vehicles within atrain.

bodyside window Any window on the side of a vehicle, including cab side windowsand windows in external doors.

buffers The fittings on the end of a railway vehicle, mounted at the sidesas separate units, designed to enable longitudinal compressiveforces to be transferred between adjacent vehicles.

coupler The element which mechanically connects the vehicles together.

coupling system The mechanical system, including buffers (where fitted), drawgearand gangway (where fitted), that connects two rail vehiclestogether, and the electrical and pneumatic connections (wherefitted) between vehicles.

crush Equivalent to "mass under exceptional payload" as defined inBS EN 15663:2017+A1:2018. For passenger vehicles this isnormally fully seated with standing passengers at a densityappropriate to the vehicle type and operational route. For freightvehicles this is the same as laden.

Note: This term may be applied equally to design mass andoperational mass, although there may be differences inpractice.

Note: For trains with fully reserved seating, such as Eurostaroperation, there will be no standing passengers.

drawgear A set of fittings used to connect railway vehicles for the purpose oftransmitting longitudinal forces between adjacent vehicles;connection can be made manually or automatically.

external door A door on the side or end of a vehicle which provides accessbetween the outside and the inside.

failure Structural defect or defects, which render the vehicle no longer safefor normal operation.

Note: Failure can arise from overload, fatigue loads,corrosion, degradation or any combination of these.

flange-back That part of the vertical surface of a wheel which forms the insideface of the wheel rim above rail level and which is the referenceface for specifying all wheel profile dimensions. It is also used as adatum face for maintenance checking of a wheelset.



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freight vehicle or wagon Vehicles designed and used for carrying payloads which do notinclude people.

jacking The action of raising a vehicle or part of a vehicle by pushingupwards from underneath using appropriate equipment such asjacks.

jacking or lifting point Designated location or housing designed for supporting the weightof a vehicle, or part of a vehicle, when using lifting jacks, liftingbrackets and slings, or other means of vertical or horizontalsupport.

laden Equivalent to "mass under normal payload" as defined inBS EN 15663:2017+A1:2018. For passenger vehicles this could befully seated but may include some standing passengers, dependingon the vehicle type and operational route.


lifeguard A structural element positioned in front of a wheel with theobjective of preventing small obstacles from entering the 'nip'between the wheel and the rail and thereby causing the wheel tolift with a consequent risk of derailment. Referred to as a 'lifeguard' in the LOC & PAS TSI.

lifting The action of raising a vehicle or part of a vehicle by pullingupwards from above using appropriate equipment such as cranes.

obstacle deflector A structural device placed at the leading end of a rail vehicle withthe objective of shielding the leading wheelset and removing anylarge obstacles from the path of the train.

primary structures For the purposes of this document, primary structures areconsidered to be those elements of a vehicle whose primarypurpose is to withstand or distribute the loads seen in normaloperation and in exceptional circumstances such as collisions orderailments. Primary structural elements include:

a) Bodyshellb) Bogiesc) Structural elements required for crashworthinessd) Couplers and drawgeare) Equipment rafts and casesf) Jacking and lifting features

rail vehicle A vehicle designed for operation on a railway, excluding those usedwithin a possession only.

recovery The process of clearing the railway line of a vehicle that has beenimmobilised as a result of collision, derailment, accident or otherincident.


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refurbishment A programme of interior/exterior work undertaken on a vehicle torestore or enhance the level of design, performance or thematerials used in its construction.

secondary structuralelements

For the purposes of this document, secondary structural elementsare considered to be those elements of a vehicle which interfacedirectly with passengers or traincrew. Secondary structuralelements include:

a) Windscreensb) Windowsc) Doorsd) Gangwayse) Interiors, for example, seats, tables, panelling and

partitions.

significant permanentdeformation

Non-elastic deformation of a structure which results in permanentdisplacement from its normal position.

Note: Such displacement could be either visible or such thatthe structure's normal function is adversely affected.

spall Particles detached from the inner face of a windscreen or window,when the outer face is subject to impact.

survival space The minimum space occupied by a person necessary for thatperson to survive.

tare Equivalent to "mass in working order" as defined inBS EN 15663:2017+A1:2018.


translator vehicle A barrier vehicle equipped with different type of coupler or inter-vehicle connections at each end to allow trains to be formed ofotherwise incompatible vehicles, having, for example, differentbraking systems.

vehicle type For the purposes of this document this shall mean a group ofvehicles which have similar design and operating characteristicsand with identical electrical circuitry associated with train wiresand their function.

wheel profile That part of the surface of the wheel or tyre between the flange-back and the outside face of the wheel or tyre.

wheelskate A device for rescuing crippled vehicles where a wheelset is not fit torotate, by lifting the affected wheelset clear of the rails andproviding alternative support and guidance through the device’swheels.



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windscreen A predominantly forward-facing window at the end of a train,behind which passengers or staff may be located.


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References

The Standards Catalogue gives the current issue number and status of documents published byRSSB. This information is available from http://www.rssb.co.uk/railway-group-standards.co.uk.

RGSC 01 Railway Group Standards Code

RGSC 02 Standards Manual

Documents referenced in the text

Railway Group Standards

GMRT2100 issue six Rail Vehicle Structures

RSSB Documents

GMGN2688 issue two Guidance on Designing Rail Freight Wagons for use on the GBMainline Railway

RIS-2790-RST issue one Compatibility of Rail Vehicle Couplings and Interconnectors

RIS-8270-RST issue one Route Level Assessment of Technical Compatibility betweenVehicles and Infrastructure

RSSB Research Report T088(2004)

Vibration environment for rail vehicle mounted equipment


Optimal design and deployment of obstacle deflectors andlifeguards


Crashworthiness of drivers' cabs: Report on consultations andrecommendations


Engineering: Requirements for train windows in passenger vehicles(Phases 1 to 7 and addendum)

SD001 issue 2:2014 Historical System data for Mechanical and Electrical Coupling ofRail Vehicles(www.rssb.co.uk/rgs/reldocs/sd001%20iss%202.pdf)

Other References

BS 7608:2014+A1:2015 Guide to fatigue design and assessment of steel products

BS 8118-1:1991 Structural use of aluminium. Part 1: Code of practice for design

BS 857:1967 Specification for Safety glass for land transport

BS EN 12663-1:2010+A1:2014

Railway applications. Structural requirements of railway vehiclebodies. Locomotives and passenger rolling stock (and alternativemethod for freight wagons)

BS EN 12663-2:2010 Railway applications. Structural requirements of railway vehiclebodies. Freight wagons



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http://www.rssb.co.uk/railway-group-standards.co.uk

BS EN 13749:2011 Railway applications. Wheelsets and bogies. Method of specifyingthe structural requirements of bogie frames

BS EN 14752:2019 Railway applications. Body side entrance systems for rolling stock

BS EN 15085-3:2007 Railway applications. Welding of railway vehicles and components.Part 3: Design requirements

BS EN 15152:2019 Railway applications. Front windscreens for train cabs

BS EN 15227:2008+A1:2010

Railway applications. Crashworthiness requirements for railwayvehicle bodies

BS EN 15827:2011 Railway applications. Requirements for bogies and running gears

BS EN 16116-1:2013 Railway applications. Design requirements for steps, handrails andassociated access for staff. Passenger vehicles, luggage vans andlocomotives

BS EN 16286-1:2013 Railway applications. Gangway systems between vehicles. Mainapplications

BS EN 16404:2016 Railway applications. Re-railing and recovery requirements forrailway vehicles

BS EN 1993-1-9:2005 Eurocode 3: Design of steel structures. Part 1-9: Fatigue

BS EN 1999-1-3:2007+A1:2011

Eurocode 9: Design of aluminium structures. Part 1-3: Structuressusceptible to fatigue

BS EN 45545-4:2013 Railway applications. Fire protection on railway vehicles. Part 4: Firesafety requirements for rolling stock design.

BS PD 6702-1:2009+A1:2019

Structural use of aluminium. Recommendations for the design ofaluminium structures to BS EN 1999

Freight Wagons TSI(WAG TSI)

Commission Regulation (EU) No 321/2013 concerning thetechnical specification for interoperability relating to thesubsystem ‘rolling stock ‒ freight wagons’ of the rail system in theEuropean Union and repealing Decision 2006/861/EC

Health and Safety at WorkAct (HASAWA)

Health and Safety at Work etc. Act 1974

Locomotives and PassengerRolling Stock TSI(LOC & PAS TSI)

Commission Regulation (EU) No 1302/2014 concerning a technicalspecification for interoperability relating to the ‘rolling stock ‒locomotives and passenger rolling stock’ subsystem of the railsystem in the European Union

Persons with ReducedMobility TSI (PRM TSI)

Commission Regulation (EU) No 1300/2014 on the technicalspecifications for interoperability relating to accessibility of theUnion's rail system for persons with disabilities and persons withreduced mobility

prEN 15227:2016 Railway applications. Crashworthiness requirements for railwayvehicle bodies. Draft for public comment

RAIB Report 05/2016 Derailment of passenger train at Godmersham, Kent, 26 July 2015


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Railway Accident Report onthe Derailment thatoccurred on 30th July 1984near Polmont

Department of Transport, HMSO, ISBN 0 11 550685 3,(www.railwaysarchive.co.uk/documents/DoT_Polmont1984.pdf)

Regulations concerning theInternational Carriage ofDangerous Goods by Rail(RID)

Convention concerning International Carriage by Rail (COTIF) -Appendix C: 1 January 2019, plus list of corrections NOT-RID-19004 08.03.2019

UIC 651:2002 Layout of driver's cabs in locomotives, railcars, multiple unit trainsand driving trailers, edition 4

UIC IRS 50564-3:2018 Railway application - Rolling stock - Passive safety

VDI 2230 Verein Deutsche Ingenieure (German Association of Engineers)Guideline: Systematic calculation of high duty bolted joints, 2014.



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