railway infrastructure - survey · railway infrastructure - survey ... or heritage railways...

AS 7634:2017

R a i l w a y I n f r a s t r u c t u r e - S u r v e y

Infrastructure Standard

AS 7634:2017

Railway Infrastructure - Survey

RISSB ABN 58 105 001 465 Page 1 Accredited Standards Development Organisation

This Australian Standard® AS 7634 Railway Infrastructure - Survey was prepared by a Rail Industry Safety and

Standards Board (RISSB) Development Group consisting of representatives from the following organisations:

Queensland Rail Aurizon Operations Limited Pacific National

ARTC TfNSW Sydney Trains

WSP

The Standard was approved by the Development Group and the Infrastructure Standing Committee in March, 2017.

On March 23, 2017 the RISSB Board approved the Standard for release.

This standard was issued for public consultation and was independently validated before being approved.

Development of the Standard was undertaken in accordance with RISSB’s accredited process. As part of the

approval process, the Standing Committee verified that proper process was followed in developing the Standard.

RISSB wishes to acknowledge the positive contribution of subject matter experts in the development of this Standard.

Their efforts ranged from membership of the Development Group through to individuals providing comment on a draft

of the Standard during the open review.

I commend this Standard to the Australasian rail industry as it represents industry good practice and has been

developed through a rigorous process.

Paul Daly

Chief Executive Officer

Rail Industry Safety and Standards Board

Keeping Standards up-to-date

Australian Standards developed by RISSB are living documents that reflect progress in science, technology and

systems. To maintain their currency, Australian Standards developed by RISSB are reviewed every seven years,

and new editions are published. Between editions, amendments may be issued. Australian Standards developed by

RISSB may also be withdrawn.

It is important that readers assure themselves they are using a current Australian Standard developed by RISSB,

which should include any amendments that may have been issued since the Standard was published. Information

about Australian Standards developed by RISSB, including amendments, can be found by visiting www.rissb.com.au.

RISSB welcomes suggestions for improvements, and asks readers to notify us immediately of any apparent

inaccuracies or ambiguities. Members are encouraged to use the change request feature of the RISSB website at:

http://www.rissb.com.au/products/. Otherwise, please contact us via email at [email protected] or write to Rail

Industry Safety and Standards Board, PO Box 4271, Kingston ACT 2604, Australia.

http://www.rissb.com.au/

http://www.rissb.com.au/products/

mailto:[email protected]

AS 7634:2017



AS 7634:2017


Document details

First published as: AS 7634:2017

ISBN 978-1-76035-703-0

Published by SAI Global Limited under licence from the Rail Industry Safety and Standards Board,

PO Box 4271, Kingston ACT 2604, Australia

Copyright

© RISSB

All rights are reserved. No part of this work may be reproduced or copied in any form or by any means, electronic or

mechanical, including photocopying, without the written permission of RISSB, unless otherwise permitted under the

Copyright Act 1968.

Notice to users

This RISSB product has been developed using input from rail experts from across the rail industry and represents

good practice for the industry. The reliance upon or manner of use of this RISSB product is the sole responsibility of

the user who is to assess whether it meets their organisation’s operational environment and risk profile.

AS 7634:2017



Document control

Document identification

Designation / Title

AS 7634:2017 Railway Infrastructure - Survey

Document history

Publication Version Effective Date Reason for and Extent of Change(s)

2017 March 23, 2017 First Publication

Approval

Name Date

Rail Industry Safety and Standards Board 23/03/2017

AS 7634:2017



Contents

1 Introduction ................................................................................................................... 6

1.1 Purpose .......................................................................................................... 6

1.2 Scope ............................................................................................................. 6

1.3 Compliance ..................................................................................................... 6

1.4 Referenced documents ................................................................................... 7

1.4.1 Normative references ...................................................................................... 7

1.5 Definitions ....................................................................................................... 7

1.6 Abbreviations .................................................................................................. 9

2 Planning ....................................................................................................................... 9

2.1 General ........................................................................................................... 9

2.2 Competency.................................................................................................. 10

2.3 Strategy ........................................................................................................ 10

2.4 Categories of Railway Survey Systems ......................................................... 10

2.4.1 National Geospatial Reference System ......................................................... 10

2.4.2 Non-National Geospatial Reference System ................................................. 11

2.5 Instrumentation, Tools and Equipment .......................................................... 11

2.5.1 Specialised Tools and Equipment ................................................................. 11

2.5.2 Instrumentation ............................................................................................. 12

3 Implementation ........................................................................................................... 13

3.1 Application of the Rail Survey Control Network ............................................. 13

3.1.1 Rail Survey Control Marks ............................................................................ 13

3.1.2 Placement of Rail Survey Control Marks ....................................................... 13

3.1.3 Installation of Rail Survey Control Marks ....................................................... 14

3.2 Application of the Track Control or Monument Network ................................ 15

3.2.1 Track Control Marks ...................................................................................... 15

3.2.2 Placement of Track Control Marks ................................................................ 15

3.3 Survey Mark Identification Requirements ...................................................... 16

3.3.1 Coordinated Survey Networks....................................................................... 16

3.3.2 Non-Coordinated Survey Networks ............................................................... 17

4 Observations and Reporting ....................................................................................... 17

4.1 Coordinated Survey Networks....................................................................... 17

4.1.1 Observational Requirements ......................................................................... 17

4.1.2 Reporting ...................................................................................................... 18

4.1.3 Observational Deliverables ........................................................................... 18

4.2 Non-National Geospatial Reference System Survey Networks ..................... 18

4.2.1 Local or Assumed Coordinated Survey Networks ......................................... 18

4.2.2 Non-Coordinated Survey Networks ............................................................... 19

5 Data Management and Quality Assurance.................................................................. 19

5.1 Survey Data Management System ................................................................ 19

AS 7634:2017



5.2 Records Management Requirements ............................................................ 19

5.2.1 Coordinated Networks .................................................................................. 19

5.2.2 Non-Coordinated Networks ........................................................................... 20

Appendix Contents

Appendix A Typical Railway Surveying Tasks .................................................................. 21

Appendix B Specialised Tools and Equipment used for Railway Surveying Purposes ..... 23

Appendix C Different Types of Rail Survey Control Marks - Typical Examples ................. 24

Appendix D Examples of Track Control Marks, Monuments, Plaques, and Data Plates ... 25

AS 7634:2017



1 Introduction

1.1 Purpose

The purpose of this Standard is to –

(a) specify requirements relating to the design, construction, measurement,

maintenance and monitoring of a railway survey system, to be able to support

various engineering activities undertaken within, and applicable to a modern

railway environment;

(b) achieve a standardised approach to railway engineering surveying; and

(c) provide mandatory and recommended guidance so that the rail survey system

developed is aligned with the safe operation of the railway network, in

accordance with the requirements of Rail Safety National Law.

1.2 Scope

This Standard covers surveying systems for railways as defined under AS 7630 'Railway

Infrastructure - Track Classification'.

This Standard is intended to cover railway survey systems based on –

(a) the current National Geospatial Reference Systems (NGRS) for Australia and

New Zealand; and

(b) non-NGRSs

This Standard covers railway survey system requirements and promotes current good practice.

This Standard is not specifically intended to cover urban on-street tramway, or light rail

networks, cane railways, or heritage railways operating on a private reservation, but items from

this Standard may be applied to such systems as deemed appropriate by the relevant Rail

Infrastructure Manager (RIM).

1.3 Compliance

There are two types of control contained within Australian Standards developed by RISSB:

(a) Mandatory requirements.

(b) Recommended requirements.

Each of these types of control address hazards that are deemed to require controls based on

existing Australian and International Codes of Practice and Standards.

A mandatory requirement is a requirement that the Standard provides as the only way of

treating the hazard.

Mandatory requirements are identified within the text by the term ‘shall’.

A recommended requirement is one where the Standard recognises that there are limitations to

the universal application of the requirement and that there may be circumstances where the

control cannot be applied or that other controls may be appropriate or satisfactory, subject to

agreement with the Rail Infrastructure Manager (RIM), Rolling Stock Operator (RSO), and/or

Rail Safety Regulator.

AS 7634:2017



Recommended clauses are mandatory unless the Rail Infrastructure Manager or Rolling Stock

Operator can demonstrate a better method of controlling the risk.

Recommended requirements are to be considered when compliance with the Standard is being

assessed.

Recommended requirements are identified within the text by the term ‘should’.

Hazards addressed by this Standard are listed on the RISSB website www.rissb.com.au

1.4 Referenced documents

1.4.1 Normative references

The following documents are referred to in this Standard:

(a) Rail Safety National Law.

(b) AS 7630 Railway Infrastructure - Track Classification.

(c) RISSB National Guideline - Glossary of Railway Terminology.

(d) ICSM Standard for the Australian Survey Control Network (SP1).

1.5 Definitions

General railway technical terms can be found in the National Guideline - Glossary of Railway

Terminology.

Specific terms used in this Standard are defined below:

Australian Height Datum (AHD): this is the geodetic datum for altitude in Australia. From

measurements taken in the late 1960s at 30 tide gauges around the mainland, and 2 tide

gauges around Tasmania, 0.000 m AHD was assigned to the mean sea level of these results.

Referred to as Australian Height Datum 1971 (AHD71) and Australian Height Datum (Tasmania)

1983 (AHD-TAS83).

Azimuth: this is the adopted meridian for a survey, based on the reference system used. This

can be determined by various means, one example being by the occupation of two marks with

known coordinates.

Best Mean Fit (BMF): this is a designed geometric alignment which minimises track slewing on

open track and as near as possible adopts the existing track alignment across timber and steel

bridges, the centre of the deck on concrete bridges and the design clearance to platforms and

other lineside structures. Best Mean Fit can refer to both horizontal and vertical centreline

design track alignments.

Datum Plate: these plates are typically fastened to structures adjacent to the track and contain

information relating to the track alignment. They have a small adjustable aluminium or plastic

block affixed to the face of the plate which acts as the reference point. As a minimum, they

should display the following information relating to this block:

Kilometrage.

Distance to the adjacent track design gauge face or centreline.

Design track superelevation.

AS 7634:2017



Additional information, such as design height to low rail and track centres for example, can be

provided if required. See also Plaque.

Detail or Topographic Survey: this is a survey carried out to provide information of sufficient

accuracy and extent for the design of the railway or other infrastructure, in brown or green field

environments.

Geocentric Datum of Australia 1994 (GDA94): this is the current geodetic datum, first

adopted nationally across Australia on 1 January 2000. The map projection associated with

GDA94 is the Map Grid of Australia 1994 (MGA94), which conforms to the Universal Transverse

Mercator Grid coordinate system. It was the first geocentric datum compatible with modern

GNSS positioning techniques adopted within Australia. GDA94 is a plate-fixed static coordinate

datum, based on a global framework, the International Terrestrial Reference Frame 1992

(ITRF92), held at the reference epoch of 1 January 1994.

Geocentric Datum of Australia 2020 (GDA2020): this is the proposed geographic coordinate

system for Australia. GDA2020 is based on a global framework, the International Terrestrial

Reference Frame (ITRF), projected to a reference date of 1 January 2020 as a conventional

plate-fixed or static datum. The shift in horizontal coordinates from GDA94 is approximately 1.8

metres.

Global Navigation Satellite System (GNSS): this is a generic term for all satellite based

positioning systems.

Global Navigation Satellite System (GNSS) Heighting: This is a height (z coordinate)

determined from GNSS observations based on the national ellipsoid model. A correction must

be applied using reliable AHD-ellipsoid separation values (N values) to determine AHD values.

Map Grid of Australia (MGA): this is a metric rectangular grid. It is a Cartesian coordinate

system based on the Universal Transverse Mercator projection and the Geocentric Datum of

Australia. The unit of measure is the metre. It is important to know what epoch the MGA is

referring to as there will be differing versions due to tectonic movement. Care needs to be

exercised to nominate which epoch the published coordinates relate to (MGA94 or MGA2020).

Monument: this is a physical structure (for example, post or concrete block) defining major

points, sometimes used for track control marks. See also Survey Monument, Track Control

Mark.

National Geospatial Reference System (NGRS): this is a combination of infrastructure, data,

software and knowledge. It includes all aspects of a coordinate datum, along with tools, utilities

and the standards and guidelines that facilitate its use.

New Zealand Geodetic Datum 2000 (NZGD2000): this is the current official geodetic datum for

New Zealand. It is based on the International Terrestrial Reference Frame 1996 (ITRF96), and

uses the Geodetic Reference System 1980 (GRS80). It manages slow crustal deformation

using a deformation model. It is a geocentric datum, compatible with GNSS. The unit of

measure is the metre, and it was implemented in 1998.

New Zealand Vertical Datum 2016 (NZVD2016): this is the current official national vertical

datum for New Zealand. It is defined by the NZGeoid2016 geoid, with normal-orthometric

heights in metres. It is consistent with NZGD2000, meaning that normal-orthometric NZVD2016

heights can be transformed to ellipsoidal NZGD2000 heights, and vice versa. It was adopted on

27 June 2016.

AS 7634:2017



Permanent Survey Mark, State Permanent Mark, Permanent Mark or State Survey Mark

(PSM, SPM, PM or SSM): These marks form part of the State Survey Control Network.

Permanent survey marks are unique to the State or Territory, and as such are registered in the

relevant State or Territory Survey Control Database (or register). The information registered

may include coordinates, height, access notes and other administrative information.

Plaque, survey plaque, datum plate, data plate, tag, label: these plates or plaques contain

information relating the rail survey control mark, track control mark or monument to the adjacent

track alignment. See also Datum Plate.

Rail Survey Control Network: this is the network of permanent rail survey control marks that

provide the survey framework for all engineering activities. This rail survey control network

consists of the physical marks, measurements, calculations and coordinates related to them.

Rail Survey Control Mark: these are permanent survey marks made of high quality, durable

and corrosion resistant materials, intended specifically for use in the railway environment and

installed in stable ground, solid rock, or in concrete in-situ, where the potential for disturbance is

minimised. They are uniquely identified, and located at regular intervals along a rail corridor,

providing the opportunity for connection to the adjacent State Survey Control Network if

required. Examples of these types of marks are provided in Appendix C.

State Survey Control Network: this is the network of physical permanent uniquely identified

ground marks, installed and maintained across a state or territory, which provide the realisation

of the National Geospatial Reference System (NGRS).

Survey Monument: these are physical structures defining significant points, sometimes used

as track control marks. In some jurisdictions, survey monuments comprise of a truncated

concrete cylinder with track alignment information stamped upon the top. See also, Monument,

Track Control Mark.

Track Control Mark (TCM): this is a mark specifically placed to provide a reference to the

design alignment of the track to which it relates.

1.6 Abbreviations

DBYD Dial Before You Dig

EDM Electromagnetic Distance Measurement

ICSM Intergovernmental Committee on Surveying and Mapping

SSP Stainless Steel Pin

2 Planning

2.1 General

Railway survey systems shall encompass all aspects of railway surveying and associated

requirements in relation to –

(a) personnel;

(b) equipment;

(c) methodology - design, working, configuration, usability;

AS 7634:2017



(d) documentation; and

(e) maintenance.

2.2 Competency

All railway survey work and associated activities detailed within this Standard shall only be

undertaken by, or under the direct supervision of, suitably qualified persons holding recognised

qualifications, as authorised and approved by the Rail Infrastructure Manager:

(a) Such authorised persons shall be responsible for the precise location of

infrastructure using surveying techniques.

(b) They are the only persons authorised to place, amend or relocate rail survey

control marks, track control marks or monuments, and any associated survey

plaques or tags.

All personnel undertaking survey work in the rail environment shall also be suitability qualified in

the safe working requirements and regulations of that jurisdiction.

Where compliance with the requirements of this Standard is not considered to be reasonably

practicable, the Rail Infrastructure Manager shall minimise identified non-compliance risks.

Lists of typical railway survey activities are in Appendix A. These lists are not exhaustive, but

are designed to provide guidance in the efficient allocation of surveying resources.

2.3 Strategy

The railway survey system shall provide –

(a) an element of assurance that the railway network can operate in a safe

manner; and

(b) a framework to support all engineering activities undertaken on a modern

railway network.

The application of a railway survey system may have different requirements, depending on the

environment in which it is located.

2.4 Categories of Railway Survey Systems

Railway survey systems shall be based upon –

(a) a National Geospatial Reference System (refer to Section 2.4.1); or

(b) a non-National Geospatial Reference System (refer to Section 2.4.2), that is –

i. an assumed, local or historic coordinate system; or

ii. an alternative system such as a non-coordinated system.

A non-National Geospatial Reference System shall only be used with the approval of the Rail

Infrastructure Manager

2.4.1 National Geospatial Reference System

Railway survey systems should be based on, and connected to, the NGRS.

AS 7634:2017



This enables coordinated track alignment to be described in the national framework, and for this

information to be integrated with mapping and other features, for example in a Geographic

Information System (GIS).

In Australia, all surveys so established shall use the current national horizontal and vertical

reference systems, namely the Geocentric Datum of Australia (GDA94), and the Australian

Height Datum (AHD71) for the Australian mainland, and (AHD-TAS83) for Tasmania.

In New Zealand, all surveys so established shall use the current national horizontal and vertical

reference systems, namely the New Zealand Geodetic Datum 2000 (NZGD2000), and the New

Zealand Vertical Datum 2016 (NZVD2016).

The horizontal and vertical datums used, and the origins and values of coordinates and heights,

shall be recorded so that full traceability is documented.

2.4.2 Non-National Geospatial Reference System

It is recognised that while some jurisdictions may have non-NGRS railway survey systems, a

compliant NGRS railway survey system represents best practice.

In some jurisdictions, to minimise calculations, specific projects may adopt local coordinate

systems. This may be useful during the construction phase of the project and to provide a

short-term solution, but when looked at from the 'whole of life' aspect, may create

interoperability issues with adjacent surveys.

There may also be historic reasons for maintaining the use of coordinate systems that are not

based on the current NGRS. When survey work is being undertaken in a non-NGRS survey

network, care shall be taken to ensure that any such work will integrate seamlessly with the

existing survey system.

In some cases, it may be necessary to provide information in multiple formats, depending on the

requirements of the Rail Infrastructure Manager.

The horizontal and vertical datums used, and the origins and values of coordinates and heights,

shall be recorded so that full traceability is documented.

Alternative systems shall only be used after consideration of the appropriate risk, and

circumstantial analysis, and then only with the approval of the Railway Infrastructure Manager.

Such alternative systems may include non-coordinated systems. Non-coordinated systems are

sometimes used in rural locations, where the cost to introduce and maintain a rail survey control

network is not warranted. Typically, the justification for the introduction of a coordinated railway

survey system will be determined by the amount and type of track maintenance that is

undertaken. For example, branch lines with minimal or seasonal rail traffic will not require

significant investment to maintain their trafficability. However, whenever any investment is

considered for these lines, this should include the installation of a compliant NGRS railway

survey system.

2.5 Instrumentation, Tools and Equipment

2.5.1 Specialised Tools and Equipment

Specialised tools and types of equipment have been developed and refined by survey

personnel working in the rail environment for many years. This equipment has been developed

AS 7634:2017



to meet the issues and exacting standards required for the purposes of rail survey control and

track control. There is also the requirement for this equipment to be robust enough to withstand

a harsh work environment.

These tools shall be calibrated prior to their use, and on an ongoing basis, as deemed

appropriate by the Rail Infrastructure Manager.

Some examples of these specialised tools and equipment are listed below:

(a) Right-angled offset prism.

(b) Coping tool.

(c) Track bar.

(d) Magnetic rail prism.

Examples of this type of equipment are illustrated in Appendix B.

The use of metallic and invar staves shall not be permitted on any railway projects. Only non-

conductive certified staves shall be used.

Any other equipment used that has the potential to impact upon, or adversely affect any

electrical, signalling or other critical equipment, shall be certified as insulated and safe for use in

the rail environment.

2.5.2 Instrumentation

Instrument specifications shall be based on the equipment recommendations outlined in the

Intergovernmental Committee on Surveying and Mapping (SP1) document 'Guideline for

Conventional Traverse Surveys' for total station instruments, and 'Guideline for Control Surveys

by Differential Levelling' for differential levelling instruments.

Instrument specifications for GNSS equipment shall be based on the recommendations outlined

in the Intergovernmental Committee on Surveying and Mapping (SP1) document 'Guideline for

Control Surveys by GNSS'.

Instrumentation and survey techniques for other types of surveys shall be compatible with the

type of work being undertaken, and shall be agreed to in consultation with the Rail Infrastructure

Manager.

It is recognised that many survey tasks can be undertaken using innovative methods rather than

conventional survey methods. However, before any work is undertaken using non-traditional

survey methods or techniques, the proposed methodology shall be thoroughly investigated and

accepted by the Rail Infrastructure Manager.

The Rail Infrastructure Manager shall confirm that where any work is undertaken using non-

conventional survey techniques, care shall be taken to ensure that the accuracy required for the

purpose and/or output of the survey is maintained.

All survey equipment shall be maintained in good adjustment (within equipment manufacturers’

stated precisions) and condition.

Examples of information required to ensure equipment is in good working order include –

(a) an annual service certificate confirming that the instrumentation meets

minimum operating specifications;

AS 7634:2017



(b) details of tests, such as component calibration, alignment and self-tests

performed in the last 12 months which show the equipment to be achieving

the required precision and accuracy; and

(c) details of measurements undertaken along an EDM Test Baseline, either

annually or immediately after instrument servicing, to ensure the legal

traceability of the measuring equipment.

Requirements relating to the accuracy of rail survey control, in terms of survey uncertainties for

the various types of instrumentation outlined above, are detailed in Section 4.1.1.

3 Implementation

3.1 Application of the Rail Survey Control Network

The rail survey control network shall have appropriate connections to the State or Territory

Survey Control Network. These connections shall be agreed to in consultation with the Rail

Infrastructure Manager before work commences.

The safety of survey personnel and equipment shall be of paramount importance when

designing rail survey control networks and installing rail survey control marks.

3.1.1 Rail Survey Control Marks

Rail survey control marks are permanent survey marks and shall be assigned a unique

identifier.

All marks used for rail survey control shall have the following characteristics:

(a) Made of high quality, durable and corrosion resistant materials.

(b) Installed in stable ground or in solid rock.

(c) Installed in locations that minimise their likelihood of being disturbed.

Examples of the types of marks that can be used for rail survey control marks include –

(a) survey pillar;

(b) brass plug or triangle;

(c) star picket set in concrete; and

(d) stainless steel nail and washer

Examples of these types of marks are illustrated in Appendix C.

Where necessary, temporary rail survey control marks (such as pegs, nails in rock or star

pickets) may be installed for a short term and a specific purpose.

However, permanent rail survey control marks shall be installed and observed as a mandatory

requirement for project handover, as required and approved by the Rail Infrastructure Manager.

3.1.2 Placement of Rail Survey Control Marks

Where practicable, the placement of rail survey control marks should, at regular intervals, allow

for connection to relevant State or Territory Survey Control Marks external to the rail corridor.

AS 7634:2017



Rail survey control marks shall be –

(a) placed at regular intervals as determined by the Rail Infrastructure Manager;

(b) positioned adjacent to the track such that they are easily accessible and

useable by all railway maintenance staff working in the operational corridor;

and

(c) placed in stable accessible ground, clear of running lines and as far as is

practicable, clear of access roads and other areas that may pose a risk to

persons (when occupying or accessing the mark), rail or road traffic.

Rail survey control marks shall be so placed to ensure that a complete coverage of the rail

network is achieved.

Rail survey control marks should not be established outside of the railway corridor.

The appropriate risk assessment procedures and approval from the Rail Infrastructure Manager

shall be obtained, prior to any placement of rail survey control marks in restricted locations such

as tunnels and viaducts.

Rail survey control marks shall be placed with the long-term strategic aim of Survey Control

densification in mind, and with their usefulness in terms of intervisibility and future connections

to adjacent surveys considered.

3.1.3 Installation of Rail Survey Control Marks

Where possible, rail survey control marks shall be installed –

(a) in stable structures, such as concrete, stone, masonry or solid rock;

(b) countersunk with the surrounding surface, to ensure that the mark does not

constitute a tripping hazard, and to minimise the risk of accidental damage or

destruction;

(c) clear of the danger zone;

(d) as far as is practicable, clear of access roads or other hazards that can pose a

risk to survey staff and instrument safety when the mark is being occupied;

(e) in a manner, such that a levelling staff can be placed upon the mark without

interference; and

(f) securely, using a bonding compound such as two-part epoxy or equivalent to

ensure adequate adhesion.

The rail survey control mark shall be suitably identified by paint or surrounding star pickets, both

to advise of its location and to afford a degree of protection from accidental damage.

In circumstances where it is not possible to install the rail survey control mark in stable ground,

a suitable design and construction methodology shall be approved by the Rail Infrastructure

Manager and applied to ensure the stability and durability of the installed mark.

Such a mark could consist of a stainless steel or brass rod, or galvanised star picket driven to

refusal, capped with a concrete collar and preferably protected by a cast iron cover box flush

with the finished surface; or where ground stability is suitable, a mark installed in concrete in-

situ.

AS 7634:2017



In all cases where ground penetration is a requirement, a services search of the site such as a

Dial Before You Dig (DBYD) and/or any state jurisdictional specific services search shall be

undertaken as determined by the Rail Infrastructure Manager.

The services search is undertaken to ensure –

(a) that no buried services are damaged; and

(b) the safety of the personnel involved.

3.2 Application of the Track Control or Monument Network

The track control marking or monument network is a further breakdown of the rail survey control

network, and shall be established using the same coordinate reference system.

These networks are installed to provide a reference to the design alignment of the track to

which they relate.

A non-coordinated survey network shall only be applied in rural locations where coordinated

track alignment is not available, has not been defined, or in other specific circumstances as

indicated and approved by the Rail Infrastructure Manager.

The frequency and permanency of track control marks shall be related to, and appropriate for

the purpose of their installation.

3.2.1 Track Control Marks

Track control marks or monuments are permanent survey marks and shall be assigned a unique

identifier.

All marks installed for the purpose of permanent track control shall have the following

characteristics:

(a) Made of high quality, durable and corrosion resistant materials.

(b) Installed in stable ground, solid rock, or solid structures such as posts or

overhead wiring structures.

Examples of the types of marks that can be used for permanent track control include –

(a) stainless steel pins;

(b) brass or steel bars;

(c) spiggots;

(d) star pickets;

(e) survey monuments;

(f) mast bolts;

(g) rail section, channel iron or post in concrete;

(h) galvanised iron or black pipe.

Examples of these types of marks are illustrated in Appendix D.

3.2.2 Placement of Track Control Marks

Track control marks or monuments shall –

AS 7634:2017



(a) be located at regular intervals as determined by the Rail Infrastructure

Manager; and

(b) more frequently located on curved track as compared to tangent track.

Track control marks or monuments shall be positioned adjacent to the track, such that they are

easily accessible and useable by all railway maintenance staff working in the operational

corridor.

Track control marks or monuments shall be placed in a manner that is not hazardous to

pedestrians, rail or road traffic.

In electrified areas as a minimum, track control marks or monuments shall be located at every

overhead wiring structure.

At locations with restricted clearance such as platforms, tunnels and bridges, track control

marks or monuments shall be placed at more frequent intervals in line with risk requirements

and as agreed with the Rail Infrastructure Manager.

Marks placed for the purposes of non-coordinated networks are normally located at set

intervals, and at a set offset relative to the referenced track.

In all cases where ground penetration is a requirement, a services search of the site such as a

Dial Before You Dig (DBYD) and/or any state jurisdictional specific services search shall be

undertaken as determined by the Rail Infrastructure Manager.

The services search is undertaken to ensure –

(a) that no buried services are damaged; and

(b) the safety of the personnel involved.

3.3 Survey Mark Identification Requirements

3.3.1 Coordinated Survey Networks

In addition to the physical mark being installed in the ground or in a wall or cutting, an identifying

plaque, marker, datum plate or tag shall be affixed to or attached adjacent to the physical mark.

This identifier shall provide by embossing, marking, engraving or by electronic means the

following information:

(a) Kilometrage of the mark (if applicable, preferably to the mm).

(b) Design superelevation / cant (in mm) of the track adjacent to the mark.

(c) Design offset (in mm) from the mark to the adjacent track / rail running face.

(d) Additional information as required.

Such additional information may include –

(a) height from the mark (up or down in mm) to the low rail of the adjacent track;

(b) design radius of the circular curve (in mm) if the mark is located adjacent to a

circular curve;

(c) information relating to the track being referenced (for example, track name,

designation, code);

AS 7634:2017



(d) design track centres between the track being referenced and an adjacent

track;

(e) information relating to the mark attachment location (for example, overhead

wiring structure number, road over-line bridge name); and

(f) point number or unique identifier of the reference mark.

Different types of plaques, markers, datum plates or tags are illustrated in Appendix D.

3.3.2 Non-Coordinated Survey Networks

Identifying markers should be placed at track control marks or monuments located adjacent to

the major track geometry or spring points. These track control marks shall have a marker,

datum plate or tag affixed to, or attached adjacent to the physical mark, with information relating

to the major track geometry or spring point.

Generally, track control marks placed in non-coordinated networks are installed at a regular

defined frequency and offset to the referenced track. Due to their defined location, unless

otherwise indicated by the Rail Infrastructure Manager, each of these marks may not require an

accompanying marker, datum plate or tag.

4 Observations and Reporting

4.1 Coordinated Survey Networks

4.1.1 Observational Requirements

The rail survey control and track control networks shall be designed to be observed using

conventional total station traverse and radiation (terrestrial) survey techniques.

Where GNSS observations are used to incorporate baseline information with the terrestrial

survey information, the observations and reductions shall be designed to achieve a survey

uncertainty of < 15 mm for horizontal position, based upon the techniques documented in the

ICSM (SP1) document 'Guideline for Control Surveys by GNSS', unless otherwise advised by

the Rail Infrastructure Manager.

For conventional (terrestrial) survey observations, the methods employed shall be designed to

achieve a survey uncertainty of < 2 mm, based on the requirements outlined in the ICSM (SP1)

document 'Guideline for Conventional Traverse Surveys', unless otherwise advised by the Rail

Infrastructure Manager.

Survey observation requirements and techniques for track control and other information shall be

as specified by the Rail Infrastructure Manager.

Alternative survey techniques that may be more appropriate for the task may be considered for

surveys other than rail survey control and track control, for example detail surveys.

Heights for rail survey control and track control shall be determined using conventional

differential levelling techniques, based on AHD in Australia and NZVD in New Zealand.

The methods employed shall result in a maximum allowable misclosure between forward and

back levelling of 12 mm * √k (where k = distance in kilometres), based on the requirements

AS 7634:2017



outlined in the ICSM (SP1) document ‘Guideline for Control Surveys by Differential Levelling’,

unless otherwise advised by the Rail Infrastructure Manager.

Where AHD or NZVD information is not available within a reasonable proximity of the project,

then GNSS techniques as approved by the Rail Infrastructure Manager, shall be employed to

establish a benchmark for the project, which can subsequently be adjusted back to AHD or

NZVD from the observed ellipsoidal height.

Sufficient observations shall be made to ensure redundancies in the data set to allow a rigorous

least square adjustment to be undertaken to ensure the integrity of the observed data. Check

measurements to significant marks, including all radiated track control marks, shall be made to

ensure the integrity of the observed data.

4.1.2 Reporting

A survey report shall be provided, and contain the following information —

(a) job or project details;

(b) surveyors’ details;

(c) equipment details, observation techniques, rail survey control network details,

photographs and field notes / sketches;

(d) data processing methods and software used;

(e) least squares adjustment details, accuracies and software used, constraints,

options, analysis and results; and

(f) any other relevant details as required by the Rail Infrastructure Manager.

4.1.3 Observational Deliverables

Observed survey data for rail survey control and track control shall be provided in a format as

mandated by the Rail Infrastructure Manager.

All data should be compatible with the requirements of the respective State or Territory

surveying and mapping agencies for integration into their geodetic control networks.

The datasets shall be provided to the Rail Infrastructure Manager with sufficient information to

ensure traceability, and in such a format that they will be available for future readjustment of the

rail survey control network.

4.2 Non-National Geospatial Reference System Survey Networks

4.2.1 Local or Assumed Coordinated Survey Networks

In addition to any requirements detailed in Section 4.1, the Rail Infrastructure Manager may

specify other special survey requirements relating to the applicable coordinate system that will

need to be met.

Special survey requirements may include particular issues relating to observation techniques,

data collation, validation, calculation or reporting. There may also be specific requirements

relating to marks to be occupied or observed.

Any such special survey requirements shall be identified and confirmed with the Rail

Infrastructure Manager, prior to any survey activities commencing.

AS 7634:2017



4.2.2 Non-Coordinated Survey Networks

Observation techniques and calculation systems employed for data collected using

measurement methods applicable to non-coordinated railway systems, shall be as determined

by the Rail Infrastructure Manager.

5 Data Management and Quality Assurance

5.1 Survey Data Management System

Each Rail Infrastructure Manager shall maintain all survey data in an appropriate data

management system, enabling safe and secure storage, searching and management of 3D

coordinate and other information relating to established ground marks within their rail survey

control network and track control network.

In relation to survey data management, the Rail Infrastructure Manager shall specify and define

the following -

(a) Data formats; and

(b) The method required for recording the location of all permanent rail survey

control and track control marks or monuments.

The data management system shall be accessible to all relevant and authorised parties as

required.

All rail survey control marks and track control marks shall be appropriately recorded and

classified, with approved implemented processes for the functions of maintenance, inspection

and repair / replacement.

With regards to the maintenance and upkeep of the rail survey control and track control

networks, some of the issues that the Rail Infrastructure Manager needs to consider include –

(a) is the mark still available?

(b) has any movement of the mark been identified? and

(c) have any adverse reports been received from, or issues identified by users of

the mark?

Where rail survey control and/or track control marks have been destroyed, removed, damaged

or displaced, obliterated or defaced, the affected marks shall be replaced unless otherwise

advised by the Rail Infrastructure Manager.

In the case of track control marks, a new or revised plaque or datum plate shall also be

installed. Any such work shall be undertaken in consultation with the Rail Infrastructure

Manager.

Where it is identified that there is a risk that rail survey control or track control marks may, or will

be destroyed, the Rail Infrastructure Manager should be informed at the earliest opportunity.

5.2 Records Management Requirements

5.2.1 Coordinated Networks

The Rail Infrastructure Manager shall ensure that on completion of all surveys –

AS 7634:2017



(a) all relevant railway databases are updated, including track design alignment

and clearance data; and

(b) other relevant authorities are notified.

5.2.2 Non-Coordinated Networks

The Railway Infrastructure Manager shall maintain records and databases relating to any

activities undertaken for the purposes of locating the position of non-coordinated track.

These records shall include current and historical measurement and marking sheets, to ensure

that a record is maintained of the current track position and any other conditions relating

thereto.

AS 7634:2017



Appendix A Typical Railway Surveying Tasks

Examples of different types of railway surveying projects undertaken.

(Reference Clause: 2.2)

The following list contains specific examples of survey tasks undertaken by surveyors within the

railway corridor and danger zone:

Survey control (in the rail environment).

Track control, monumentation, installation and maintenance.

Detail surveys for specific requirements, by various techniques

(conventional total station, scanning, LIDAR, aerial photo).

Track design (alignment and grading), track realignment, duplication,

and bifurcation.

Track lifts and pulls.

Track work on ballasted track, track slabs, transition slabs, direct

fixation.

Precise monitoring for deformation, settlement movement and erosion.

Track reconditioning, track renewal, track maintenance.

Turnout, crossover and special track work installation or renewal.

Kinematic structure clearance surveys.

Half-block replacement.

Retaining walls.

Track drainage, culverts, stormwater, open drain, effective waterway.

Underline track crossing installations, under track bores and associated

monitoring.

Location of buried services infrastructure (both rail and external).

Platform interface issues (rebuilds, awnings, coping location, platform

heights, cutbacks, platform gap reduction, level and standard access).

Under bridges; ballast top, transom top, direct fix, deck renewal or

replacement.

Overbridges; road, pedestrian, deck replacement, clearance

requirements.

Level crossing surveys.

Tunnels, deflection walls, overbridges.

Line side equipment, km posts, speed boards (regarding location and

kinematic clearance).

Signals, dwarf signals, gantries.

AS 7634:2017



Overhead wiring structures, including precast footings, portal and

planted post positioning.

OHWS drop verticals, contact wires, catenary wires, other attached

infrastructure, and cantilever calculation requirements.

Stabling yard infrastructure.

Creep measurements.

The following list provides examples of survey work undertaken within the rail corridor (but

external to the Danger Zone), where specific railway surveying competencies are NOT required:

Access roads.

Power poles and conductors (clear of the danger zone).

Earthworks, sound mounds, noise walls.

Embankments, cuttings, retaining walls.

Buried infrastructure, DBYD (clear of the danger zone).

Fencing, railway land boundary determination.

Platform works behind the yellow (safety) line.

Substation works, feeders, general electrical set out work.

Car parks, road works, kerb and gutter.

Stations, buildings.

Drainage (non-track).

Due to safety concerns for survey personnel and equipment, it may be necessary to plan for a

track possession to undertake some of these survey projects.

AS 7634:2017



Appendix B Specialised Tools and Equipment used for Railway Surveying Purposes

Reference Clause: 2.5.1 Specialised Tools and Equipment - Source TfNSW T HR TR 13000 ST

Offset prism and associated attachment arms

Right angled offset prism being used to measure a SSP

Platform Coping Tool

Magnetic Rail Prism

Track Bar used to measure track centreline

AS 7634:2017



Appendix C Different Types of Rail Survey Control Marks - Typical Examples

Reference Clause: 3.1.1 Rail Survey Control Marks

Brass Triangle type mark, details

Rail survey control marks

Survey Marks in Cast Iron Cover Boxes

Other types of Permanent Survey Control Marks

AS 7634:2017



Appendix D Examples of Track Control Marks, Monuments, Plaques, and Data Plates

Reference Clause: 3.2.1 Track Control Marks

Brass Bar and Survey Plaque

Datum Plate

Track Data Plate

SSP and Survey Plaque

Brass Bar TCM in Platform

Typical locations for TCMs

Brass Bar type survey mark

Stainless Steel Pin type survey mark

90 - 100

12

– 1

2.7

2 X 1mm chamfer

2

AS 7634:2017



About Rail Industry Safety and Standards Board

The Rail Industry Safety and Standards Board is a not for profit company limited by guarantee. Wholly owned by its

funding members, RISSB is required to apply the whole of its income and assets to achieving the objects listed in its

constitution.

RISSB is responsible for the development and management of Standards, Rules, Codes of Practice and Guidelines

for the Australian rail industry.

For further information, visit www.rissb.com.au

RISSB Australian Standards Development Process

The Standards development process is rigorous and transparent.

Authors work with RISSB's Project Managers and Development Groups to ensure that products are acceptable to

industry. Standing Committees oversee this work and ensure that proper governance and process is followed. The

products are exposed to the public and industry for comment, and validated by an independent validator.

Once agreed by the Development Groups, Standing Committees and Validator, the drafts are passed to the RISSB

Board for approval.

The same process is used in developing other RISSB products, although Guidelines are not exposed to the public for

comment or validated, given their non-binding nature.

Standards Development and Accreditation Committee

RISSB is accredited by the Standards Development and Accreditation Committee (SDAC), and all Standards

produced by RISSB since 31 July 2007 are published as Australian Standards.

The Standards Development and Accreditation Committee audits RISSB annually to ensure that RISSB’s processes

are in accordance with SDAC accreditation requirements.

Sales and distribution

Australian Standards developed by RISSB are sold and marketed through SAI Global. For further information, please

visit www.saiglobal.com.

Financial members of RISSB are granted access with membership.

http://www.rissb.com.au/

ISBN Enter ISBN.

ABN 58 105 001 465

For information regarding the development of Australian Standards developed by RISSB contact:

Rail Industry Safety and Standards Board Suite 4, Level 4, Plaza Offices (East) Terminal Complex, Canberra Airport ACT 2609 Australia

PO Box 4271, Kingston ACT 2604, Australia

Telephone: 07 3724 0000 (Int. call: +61 7 3724 0000)

Fax: (02) 6270 4516 (Int: +61 2 6270 4516)

email: [email protected]

For information regarding the sale and distribution of Australian Standards developed by RISSB contact:

SAI Global Limited Phone: 13 12 42 Fax: 1300 65 49 49 Email: [email protected] http://infostore.saiglobal.com/store

ISBN: 978-1-76035-703-0



http://infostore.saiglobal.com/store

railway infrastructure - survey · railway infrastructure - survey ... or heritage railways...

Documents