SIST-TP CEN/TR 16978:2016

Railway applications - Infrastructure - Survey on isolated defects

This Technical Report describes the methodology used for the survey on Isolated Defects (ID) and gives the results.

Bahnanwendungen - Infrastruktur - Überblick von Einzelfehlern

Applications ferroviaires - Infrastructure - Étude relative aux défauts isolés

Železniške naprave - Infrastruktura - Pregled posameznih okvar

To tehnično poročilo opisuje metodologijo za pregled posameznih okvar (ID) in podaja rezultate.

General Information

• Status: Published
• Public Enquiry End Date: 05-Apr-2016
• Publication Date: 16-Oct-2016
• ICS: 45.020 - Railway engineering in general
• ICS: 93.100 - Construction of railways
• Technical Committee: IŽNP - Reilway applications
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 14-Oct-2016
• Due Date: 19-Dec-2016
• Completion Date: 17-Oct-2016
• Ref Project: CEN/TR 16978:2016 - Railway applications - Infrastructure - Survey on isolated defects

Overview

CEN/TR 16978:2016 - "Railway applications - Infrastructure - Survey on isolated defects" is a CEN Technical Report that documents the methodology and results of a European Survey on Isolated Defects (ESID). Prepared by CEN/TC 256, the report supports development of the EN 13848 track geometry series by providing comparative data on isolated exceedances of track-geometry thresholds across participating national networks. Urban rail is excluded.

Key search keywords: CEN/TR 16978:2016, Isolated Defects, track geometry, railway infrastructure, EN 13848, track measurement.

Key topics and technical scope

• Objective: Describe the methodology used to collect and analyse isolated defects (IDs) and present cumulative results across networks.
• Definition of Isolated Defect: A section of a measurement signal exceeding a given threshold (e.g., Immediate Action Limit) with at least one sample; length measured by number of samples.
• Measurement basis: Typical measurement spacing 0.25 m; survey used most recent measurement per location and produced cumulative frequency distributions of length of exceedances.
• Parameters investigated: Eight track-geometry parameters, including:
  • Longitudinal level (LL) in wavelength domains D1 (3 m < λ ≤ 25 m) and D2 (25 m < λ ≤ 70 m)
  • Alignment (AL) in D1 and D2
  • Mean gauge (average over 100 m)
  • Twist on a 3 m base
  • Narrow and wide gauge deviations
• Speed classes: Data separated into five speed bands per EN 13848: V ≤ 80 km/h; 80 < V ≤ 120 km/h; 120 < V ≤ 160 km/h; 160 < V ≤ 230 km/h; 230 < V ≤ 300 km/h.
• Data processing & anonymity: Networks provided representative samples (minimum 10% where full-network data unavailable); submissions were anonymized and weighted to compute European exceedance lengths. Disclosure of raw assignments is restricted.

Practical applications

• Benchmarking track-geometry quality across national networks.
• Supporting specification and calibration of EN 13848 threshold values (including Immediate Action Limits).
• Prioritizing maintenance and defect remediation by quantifying the length and frequency of exceedances.
• Risk assessment for derailment potential and operational decisions (speed restrictions, line closures).
• Input for procurement and validation of track measurement systems and data-processing tools.

Who should use this report

• Infrastructure managers and track maintenance planners
• Railway safety and risk assessors
• Track engineers and condition-monitoring specialists
• National standards bodies and working groups developing or applying EN 13848
• Suppliers of track measurement equipment and data-analysis software

Related standards

• EN 13848-1 (Track geometry characterisation)
• EN 13848-5 (Geometric quality levels - Plain line)

CEN/TR 16978:2016 is a practical reference for understanding how isolated track-geometry defects are identified, quantified and compared across European railway networks to inform maintenance, safety and standardization.

Standards Content (Sample)

SLOVENSKI STANDARD
01-december-2016
Železniške naprave - Infrastruktura - Pregled posameznih okvar
Railway applications - Infrastructure - Survey on isolated defects
Bahnanwendungen - Infrastruktur - Überblick von Einzelfehlern
Applications ferroviaires - Infrastructure - Étude relative aux défauts isolés
Ta slovenski standard je istoveten z: CEN/TR 16978:2016
ICS:
45.020 Železniška tehnika na Railway engineering in
splošno general
93.100 Gradnja železnic Construction of railways
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

CEN/TR 16978
TECHNICAL REPORT
RAPPORT TECHNIQUE
October 2016
TECHNISCHER BERICHT
ICS 93.100
English Version
Railway applications - Infrastructure - Survey on isolated
defects
Bahnanwendungen - Infrastruktur - Überblick von
Einzelfehlern
This Technical Report was approved by CEN on 23 May 2016. It has been drawn up by the Technical Committee CEN/TC 256.

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

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2016 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN/TR 16978:2016 E
worldwide for CEN national Members.

Contents Page
European foreword . 4
Introduction . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 Symbols and abbreviations . 6
5 Methodology . 7
5.1 General considerations . 7
5.2 Collected data . 7
5.2.1 Scope of survey. 7
5.2.2 Speed classes. 8
5.2.3 Parameters investigated . 8
5.2.4 Calculation of lengths of exceedances . 9
5.2.5 Data processing . 9
6 Participating networks and involvement . 10
6.1 Participating networks . 10
6.2 Coverage . 10
7 Results . 11
7.1 General remarks . 11
7.2 Results for longitudinal level in D1 . 11
7.3 Results for alignment in D1 . 12
7.4 Results for mean gauge over 100 m . 13
7.5 Results for twist on a base of 3 m . 14
7.6 Results for narrow gauge . 15
7.7 Results for wide gauge . 16
7.8 Results for longitudinal level in domain D2 . 17
7.9 Results for alignment in domain D2 . 18
Annex A (informative) Spread of collected data . 19
A.1 General . 19
A.2 Results for longitudinal level in D1 with V ≤ 80 km/h . 19
A.3 Results for longitudinal level in D1 with 80 km/h < V ≤ 120 km/h . 20
A.4 Results for longitudinal level in D1 with 120 km/h < V ≤ 160 km/h . 21
A.5 Results for longitudinal level in D1 with 160 km/h < V ≤ 230 km/h . 22
A.6 Results for longitudinal level in D1 with 230 km/h < V ≤ 300 km/h . 23
A.7 Results for alignment in D1 with V ≤ 80 km/h . 24
A.8 Results for alignment in D1 with 80 km/h < V ≤ 120 km/h . 25
A.9 Results for alignment in D1 with 120 km/h < V ≤ 160 km/h . 26
A.10 Results for alignment in D1 with 160 km/h < V ≤ 230 km/h . 27
A.11 Results for alignment in D1 with 230 km/h < V ≤ 300 km/h . 28
A.12 Results for mean gauge over 100 m with V ≤ 80 km/h . 29
A.13 Results for mean gauge over 100 m with 80 km/h < V ≤ 120 km/h . 30
A.14 Results for mean gauge over 100 m with 120 km/h < V ≤ 160 km/h . 31
A.15 Results for mean gauge over 100 m with 160 km/h < V ≤ 230 km/h . 32
A.16 Results for mean gauge over 100 m with 230 km/h < V ≤ 300 km/h . 33
A.17 Results for twist on a base of 3 m with V ≤ 80 km/h . 34
A.18 Results for twist on a base of 3 m with 80 km/h < V ≤ 120 km/h . 35
A.19 Results for twist on base of 3 m with 120 km/h < V ≤ 160 km/h . 36
A.20 Results for twist on a base of 3 m with 160 km/h < V ≤ 230 km/h . 37
A.21 Results for twist on a base of 3 m with 230 km/h < V ≤ 300 km/h . 38
A.22 Results for narrow gauge V ≤ 80 km/h . 39
A.23 Results for narrow gauge 80 km/h < V ≤ 120 km/h . 40
A.24 Results for narrow gauge 120 km/h < V ≤ 160 km/h . 41
A.25 Results for narrow gauge 160 km/h < V ≤ 230 km/h . 42
A.26 Results for narrow gauge 230 km/h < V ≤ 300 km/h . 43
A.27 Results for wide gauge V ≤ 80 km/h. 44
A.28 Results for wide gauge 80 km/h < V ≤ 120 km/h . 45
A.29 Results for wide gauge 120 km/h < V ≤ 160 km/h . 46
A.30 Results for wide gauge 160 km/h < V ≤ 230 km/h . 47
A.31 Results for wide gauge 230 km/h < V ≤ 300 km/h . 48
A.32 Results for longitudinal level in domain D2 with 160 km/h < V ≤ 230 km/h . 49
A.33 Results for longitudinal level in domain D2 with 230 km/h < V ≤ 300 km/h . 50
A.34 Results for alignment in domain D2 with 160 km/h < V ≤ 230 km/h . 51
A.35 Results for alignment in domain D2 with 230 km/h < V ≤ 300 km/h . 52
Bibliography . 53

European foreword
This document (CEN/TR 16978:2016) has been prepared by Technical Committee CEN/TC 256
“Railway applications”, the secretariat of which is held by DIN.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN and CENELEC shall not be held responsible for identifying any or all such patent
rights.
Introduction
The Working Group CEN/TC 256 SC1/WG 28 “Railway applications/Infrastructure/Track geometry
quality” conducted a European Survey on Isolated Defects (ESID) in order to support the process of the
development of the EN 13848 series. The goal of the survey was to get an overview of certain
thresholds of selected track geometry parameters in several European networks in terms of Isolated
Defects (ID).
This Technical Report does not include urban rail matters.
1 Scope
This Technical Report describes the methodology used for the survey on Isolated Defects (ID) and gives
the results.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
EN 13848-1, Railway applications — Track — Track geometry quality — Part 1: Characterisation of track
geometry
EN 13848-5:2008+A1:2010, Railway applications — Track — Track geometry quality — Part 5:
Geometric quality levels — Plain line
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
decolouring
algorithm which converts one signal into a different signal
Note 1 to entry: It is used in EN 13848 series to convert a chord measurement signal into a D1 or D2
measurement signal.
3.2
Immediate Action Limit
IAL
value which, if exceeded, requires taking measures to reduce the risk of derailment to an acceptable
level
Note 1 to entry: To reduce the risk of derailment can be done either by closing the line, reducing speed or by
correction of track geometry.
3.3
isolated defect
part of the signal exceeding a given limit such as IAL with at least one sample (data break)
Note 1 to entry: The length of the exceedance is given by the number of samples exceeding the limit. A
minimum length of exceedance may be applied to determine an isolated defect.
4 Symbols and abbreviations
For the purposes of this Technical Report, the following symbols and abbreviations apply.
Table 1 — Symbols and abbreviations
Symbol Designation Unit
AL Alignment mm
D1 Wavelength range 3 m < λ ≤ 25 m m
D2 Wavelength range 25 m < λ ≤ 70 m m
LL Longitudinal level mm
LoE Length of exceedance m
V Speed km/h
NOTE In this Report, AL stands for “alignment” and is not to be confused with AL standing for “alert limit” as
defined in EN 13848–5.
5 Methodology
5.1 General considerations
The objective of the European Survey on Isolated Defects (ESID) is to get an understanding and an
overview concerning isolated defects within European networks. In a first step it was ensured that at
least 6 networks showed interest in participating in this study. The initial idea was to collect the
number of isolated defects which exceed certain threshold levels. A discussion between the networks
showed very different approaches concerning definition and counting rules of such isolated defects. In
addition some networks had very limited availability of appropriate national databases and evaluation
tools and concerns regarding costs and effort of a too detailed evaluation were raised.
So the experts of CEN/TC 256/SC 1/WG 28 worked out an alternative methodology which was more
practical for most participating networks and less time consuming. First of all, the number of
measurement parameters was limited to 8. For the next step, it was agreed to base the survey on
cumulative frequency distributions of exceeding lengths. These cover at least the range of thresholds up
to and above the IALs according to EN 13848-5. That means that for each threshold of a measurement
parameter, the number of metres exceeding this threshold within the participating network were
determined.
Finally each of the participating networks provided data for a representative part of their network
according to the technical specification described below in 5.2. With the help of a standardised inquiry
form, the cumulative frequency distributions of the data were determined and were sent to the
CEN/TC 256/SC 1/WG 28 clearing office.
In order to make the data anonymous, the clearing office assigned a random network number to the
data of each network and summarized the data in anonymous charts. These were supplied to
CEN/TC 256/SC 1/WG 28 only.
Without agreement of all participating networks neither the clearing office nor
CEN/TC 256/SC 1/WG 28 may disclose or publish any of the data or the assignment between data and
participating networks as a whole or in parts to anyone else.
5.2 Collected data
5.2.1 Scope of survey
The survey collected data for all main lines of the participating networks; main tracks in stations are
included in the survey as well. Isolated switches or group of switches situated in plain line and run at
line speed are included in the provided data, unless typical errors due to measuring systems occur. In
the latter case, the respective data were excluded from the survey. In any case, all side tracks have been
excluded. This prevents counting non-representative exceedances.
The survey was based on measurements of track taken typically at 0,25 m spacing. For a network length
of 10 000 km track this would result in a cumulative frequency distribution comprising over 40 million
measurements.
The survey was conducted using the most current measurement value for each location. This was
summarized in a cumulative frequency distribution.
Where it was not possible for a participating network to do the calculation over their whole network, all
data sets containing at least 10 % of the network were taken into account while the track layout and
track quality considered in the sample had to be as representative as possible for the whole network.
The track length considered for each speed class had to be quoted in the standardised inquiry form.
5.2.2 Speed classes
The survey was done in 5 speed classes according to the EN 13848 series:
1) 230 km/h < V ≤ 300 km/h;
2) 160 km/h < V ≤ 230 km/h;
3) 120 km/h < V ≤ 160 km/h;
4) 80 km/h < V ≤ 120 km/h;
5) V ≤ 80km/h.
Speeds higher than 300 km/h were not taken into account due to the lack of sufficient data.
In order to ensure anonymity of networks with high-speed tracks, the network lengths of the
participating networks were not disclosed in the results. They were just used as weighting factors to
calculate European exceedance lengths.
5.2.3 Parameters investigated
The survey was done on the parameters in the ranges given in Table 2.
Table 2 — Parameters and studied ranges
Threshold range (min to max) for speed classes [km/h]
Parameters
V ≤ 80 80 < V ≤ 120 120 < V ≤ 160 160 < V ≤ 230 230 < V ≤ 300
Longitudinal level (LL)
for domain D1
1 (1 to 30) mm (1 to 28) mm (1 to 25) mm (1 to 22) mm (1 to 18) mm
according to
EN 13848-1
Alignment (AL) for
2 domain D1 according (1 to 24) mm (1 to 19) mm (1 to 16) mm (1 to 14) mm (1 to 12) mm
to EN 13848-1
Mean Gauge (average
over 100 m) narrow
3 (−1 to −10) mm (−1 to −9) mm (−1 to −7) mm (−1 to −7) mm (−1 to −5) mm
according to
EN 13848-1
LL for domain D2
4 according to — — — (1 to 35) mm (1 to 30) mm
EN 13848-1
AL for domain D2
5 according to — — — (1 to 26) mm (1 to 22) mm
EN 13848-1
Twist on a base of 3 m
and expressed in
6 (1 to 9) mm/m (1 to 9) mm/m (1 to 9) mm/m (1 to 9) mm/m (1 to 7) mm/m
mm/m according to
EN 13848-1
Narrow gauge
7 according to (−1 to −13) mm (−1 to −13) mm (−1 to −12) mm (−1 to −9) mm (−1 to −7) mm
EN 13848-1
Wide gauge according
8 (1 to 37) mm (1 to 37) mm (1 to 37) mm (1 to 30) mm (1 to 30) mm
to EN 13848-1
Where the origin of the measurement data for LL and AL was chord based, they were decoloured to
obtain D1.
5.2.4 Calculation of lengths of exceedances
For each of the parameters above, the length of exceedances (LoEs) were collected for all threshold
levels in steps of 1 mm according to the range of values given in Table 2, except for twist where the
LoEs were collected for threshold levels in steps of 1 per mille. All LoEs were collected in the units of
[metres per 100 km] which means it was collected from the number of metres which exceed the
threshold level related to a distance of 100 km.
For longitudinal level and alignment in domain D1 as well as D2 the exceedance lengths of left and right
rail have been added.
5.2.5 Data processing
The tables of LoEs for all participating networks for the 5 speed classes were produced and a weighted
average was calculated for each step of the frequency distribution. The line length of each participating
network in the considered speed class was used as a weighting factor. In this way ‘European Lengths of
Exceedances’ were determined for the 5 speed classes and all 8 parameters. These cumulative
frequency distributions are shown in Clause 6.
6 Participating networks and involvement
6.1 Participating networks
The following alphabetic list gives the 12 networks that provided data to the survey:
Austria ÖBB-Infrastructure
Belgium Infrabel
Czech Republic SZDC
Denmark Rail Net Denmark
France SNCF / RFF
Germany DB-Netz
Hungary MÁV
Italy RFI
Portugal IP
Sweden Trafikverket
Switzerland SBB
United Kingdom Network Rail
6.2 Coverage
The survey is comprised data for approximately 63 000 km of track. This represents a 41 % sample of
the participating networks. The total track length of all participating networks is about 154 000 km, this
is more than half of the track length of the European Union member states.
Some networks provided data for nearly all the lines, others provided smaller samples. In any case, they
have been chosen carefully as representative for the speed class in the whole network. However, just in
3 out of 34 cases, data of one network had to be removed because of poor coverage. Therefore, in these
cases, data of the concerned networks were simply not taken into account in 3 out of 34 charts.
Furthermore, the data set of 1 network was not taken into account, because of significant distortion of
the European results.
Table 3 shows the coverage of the individual speed classes related to the respective track length.
Table 3 — Sample size of track data for each speed class (points)
Speed range Network length Sample size Percentage
230 km/h < V ≤ 300 km/h 5 955 km 3 263 km 55 %
160 km/h < V ≤ 230 km/h 12 400 km 7 253 km 58 %
120 km/h < V ≤ 160 km/h 55 355 km 15 874 km 29 %
80 km/h < V ≤ 120 km/h 49 652 km 21 964 km 44 %
V ≤ 80 km/h 30 797 km 15 060 km 49 %
7 Results
...