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Technical Note - TN 017: 2015

Technical Note - TN 017: 2015

Subject: Withdrawal of ESC 320 Overbridges and Footbridges

Issued date: 13 April 2015

Effective date: 13 April 2015

For queries regarding this document [email protected]

www.asa.transport.nsw.gov.au

This technical note is issued by the Asset Standards Authority as a notification to remove from

use RailCorp document ESC 320 Overbridges and Footbridges, Version 2.2.

ESC 320 is presented as a legacy document and shall be used for reference purposed only.

ASA standard T HR CI 12030 ST Overbridges and Footbridges, Version 1.0 supersedes this

document.

Authorisation:

Technical content prepared by

Checked and approved by

Interdisciplinary coordination checked by

Authorised for release

Signature

Name Dorothy Koukari Joe Muscat John Paff Graham Bradshaw

Position Senior Engineer Standards

A/Lead Civil Engineer A/Chief Engineer Rail Principal Manager, Network Standards and Services

© State of NSW through Transport for NSW of 1

mailto:[email protected]

http://www.asa.transport.nsw.gov.au/

UNCONTROLLED WHEN PRINTED

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OVERBRIDGES AND FOOTBRIDGES

ESC 320

Engineering Standard Structures

Version 2.2

Issued July 2010

Owner: Chief Engineer Civil

Approved by: John Stapleton Authorised by: Richard Hitch A/Principal Engineer Chief Engineer Civil Technology & Standards

Page 1 of 20

Disclaimer This document was prepared for use on the RailCorp Network only. RailCorp makes no warranties, express or implied, that compliance with the contents of this document shall be sufficient to ensure safe systems or work or operation. It is the document user’s sole responsibility to ensure that the copy of the document it is viewing is the current version of the document as in use by RailCorp. RailCorp accepts no liability whatsoever in relation to the use of this document by any party, and RailCorp excludes any liability which arises in any manner by the use of this document. Copyright The information in this document is protected by Copyright and no part of this document may be reproduced, altered, stored or transmitted by any person without the prior consent of RailCorp

RailCorp Engineering Standard — Structures Overbridges and Footbridges ESC 320

© Rail Corporation Page 2 of 20 Issued July 2010 2.2 UNCONTROLLED WHEN PRINTED Version

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Document control Revision Date of Approval Summary of change

2.2 Changes detailed in Summary table below

2.1 November, 2009 Change of format for front page, change history and table of contents; minor editing and formatting.

2.0 July, 2007 Additional minor requirements re existing structures, integrated designs, approved materials, services, nameplates, construction specifications, OHW fittings, protection screens, drainage, bird nesting; Minor changes to design loads: widening or extending existing bridges; seismic loading; Criteria specified for bearings and deck joints; Additional criteria for deck structure re structurally continuous without gaps or deck joints; Criteria specified for advertising signs; Clarification of requirements for earthing and bonding; electrical clearances; fire rating; Collision protection risk table updated to be consistent with the RailCorp Safety Management System; Requirements specified for collision protection of lift structures at track level; Guard rail criteria updated: top of guard rail not more than 50mm below top of running rail; guard rail to extend 20 metres in advance of vulnerable support; Safety refuges included; Name signs included. This document replaces CTN 07/04 “Name Signs on Overbridges and Tunnels”.

1.0 March, 2006 First issue as a RailCorp document. Replaces TS 30 000 3 01 SP, CTN 01/18

Summary of changes from previous version Section Summary of change

Document Control

Update version details

All Correct internal section references

3.14 Change reference to TMC 304 to SPC 301

6.4.4 Add definition of ‘edge of travelling lanes’ for protection screens

8.6.3 Add guard rail insulation requirements from CTN 08/06


Contents


1 Purpose, Scope and Application ............................................................................................................ 5 2 References ................................................................................................................................................ 5

2.1 Australian and International Standards ......................................................................................... 5 2.2 RailCorp Documents ..................................................................................................................... 5 2.3 Other References .......................................................................................................................... 5

3 General Requirements ............................................................................................................................. 5 3.1 Design Standards .......................................................................................................................... 5 3.2 Existing Structures......................................................................................................................... 6 3.3 Integrated Designs ........................................................................................................................ 6 3.4 Approved Materials........................................................................................................................ 6 3.5 Clearances..................................................................................................................................... 6 3.6 Earthworks..................................................................................................................................... 6 3.7 Provision for Services.................................................................................................................... 6 3.8 Safety............................................................................................................................................. 7 3.9 Protection of the Environment ....................................................................................................... 7 3.10 Heritage ......................................................................................................................................... 7 3.11 Design Procedure – New or Infrequently Used Products.............................................................. 7 3.12 Nameplates and Plaques .............................................................................................................. 7 3.13 Drawing Standards ........................................................................................................................ 7 3.14 Construction................................................................................................................................... 7 3.15 Maintenance .................................................................................................................................. 8 3.16 Advertising Signs........................................................................................................................... 8

4 Design Criteria .......................................................................................................................................... 8 4.1 Overbridges ................................................................................................................................... 8 4.2 Footbridges.................................................................................................................................... 8 4.3 Widening or Extending of Existing Bridges ................................................................................... 8 4.4 Seismic Loading ............................................................................................................................ 9

5 Bearings and Deck Joints ....................................................................................................................... 9 6 Configuration Requirements................................................................................................................... 9

6.1 Bridge Decks ................................................................................................................................. 9 6.2 Overhead Wiring Fittings ............................................................................................................... 9 6.3 Stepways ....................................................................................................................................... 9 6.4 Barriers, Safety Screens and Protection Screens......................................................................... 9 6.5 Drainage ...................................................................................................................................... 11

7 Miscellaneous Design Requirements................................................................................................... 11 7.1 Electrical Requirements............................................................................................................... 11 7.2 Fire Rating ................................................................................................................................... 12 7.3 Formwork..................................................................................................................................... 12 7.4 Deck sheeting.............................................................................................................................. 12 7.5 Bird Nesting ................................................................................................................................. 12

8 Collision Protection ............................................................................................................................... 13 8.1 General ........................................................................................................................................ 13 8.2 Lift Structures...............................................................................................................................13 8.3 Location of Piers, Columns and Deflection Walls........................................................................ 13 8.4 Design Loading............................................................................................................................ 13 8.5 Structural Configuration............................................................................................................... 14 8.6 Guard Rails.................................................................................................................................. 15

9 Safety Refuges and Handhold Devices................................................................................................ 16 9.1 Provision of Safe Areas ............................................................................................................... 16

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9.2 Locations with Limited Clearances.............................................................................................. 17 9.3 Locations with Adequate Clearances .......................................................................................... 17 9.4 Location of Refuges, Handhold Devices and Signs .................................................................... 17 9.5 Refuge Details ............................................................................................................................. 18 9.6 Handhold Device Details ............................................................................................................. 18

10 Name Signs............................................................................................................................................. 19 10.1 General ........................................................................................................................................ 19 10.2 Signage Requirements ................................................................................................................ 19


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1 Purpose, Scope and Application This Standard details design requirements for overbridges and footbridges on the RailCorp network.

This Standard does not cover the load rating of overbridges and footbridges, which is to be undertaken in accordance with AS 5100.7 “Load rating of existing structures”.

Overbridges are defined as bridges over the track, carrying vehicular traffic, and may include provision for pedestrians. Footbridges are bridges over the track, carrying pedestrian traffic only, and may be freestanding or combined with an overhead booking office or retail outlets.

2 References

2.1 Australian and International Standards AS 1085.1-2002 “Railway Track Material Part 1: Steel Rails”

AS 5100-2004 “Bridge Design”

2.2 RailCorp Documents ESC 100 “Civil Technical Maintenance Plan”

ESC 302 “Defect Limits”

ESC 215 “Transit Space”

ESC 220 “Rail and Rail Joints”

SPC 301 “Structures Construction”

EP 08 00 00 07 SP “Safety Screens for Bridges over 1500 V OHW Equipment”

EP 12 10 00 21 SP “Low Voltage Installations Earthing”

EP 12 10 00 22 SP “Buildings and Structures under Overhead Lines”

EP 12 20 00 01 SP “Bonding of Overhead Wiring Structures to Rail”

EP 12 30 00 01 SP “Electrolysis from Stray DC Current”

ESG 100.17 “Signal Design Principles Track Circuits”

RailCorp Safety Management System

RailCorp Station Design Guide

2.3 Other References RTA Technical Direction TD 2002/RS02 “Policy for Safety Screening of Bridges”

3 General Requirements

3.1 Design Standards All overbridges and footbridges are to be designed to Australian Standard AS 5100 “Bridge design” and the requirements specified in this standard.

They shall also comply with the RailCorp Station Design Guide.

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3.2 Existing Structures When replacing or refurbishing an existing overbridge or footbridge, the design shall comply with Section 3.1 and shall provide for the current and proposed future line usage and business requirements.

Refurbishment includes widening or extending existing bridges, or infilling the median.

When refurbishing an existing bridge protection screens, barriers and approach barriers shall be provided in accordance with AS 5100 for the whole bridge.

The stability, capacity and serviceability of an existing structure may be impacted when modifying an existing bridge. This may arise from changes to the load paths and load magnitudes and is to be taken into account during the design process.

Disabled access legislation and policies may require the retrofitting of easy access to existing bridges. The new work is to be integrated into the existing structure taking into consideration aesthetics, material types and thermal movements etc. of the structure as a whole.

Other modifications or improvements to an existing bridge must also take into account any prior repair work that should be undertaken that would be otherwise impeded by the new work.

3.3 Integrated Designs The design of each overbridge and footbridge is to be integrated taking into account all associated requirements such as service routes, overhead wiring and signalling infrastructure, drainage, bonding and architectural treatments. Aesthetics are to be taken into account including proportions, details and finishes.

In locations that are vulnerable to vandalism and graffiti, appropriate measures are to be taken to prevent access to the adjoining rail infrastructure. Anti-graffiti paints should be specified in areas where there is a high risk of graffiti.

Overbridges and footbridges shall not be painted in safeworking colours of red, orange and green.

3.4 Approved Materials Approved construction materials for main structural elements are steel and concrete. Timber materials shall not be used as structural elements in the design of overbridges and footbridges.

Masonry is approved for existing structures and for cladding of new structures where this is required in special circumstances such as for heritage reasons.

3.5 Clearances Horizontal and vertical clearances for new overbridges and footbridges and refurbishment of existing bridges are to comply with RailCorp’s Engineering Standard ESC 215 “Transit Space”.

The design of overbridges and footbridges shall also provide clearances for safe places as detailed in Section 9 of this standard.

3.6 Earthworks Earthworks associated with the approaches to overbridges and footbridges are to be designed in accordance with RTA specifications.

3.7 Provision for Services Provision may be required when designing overbridges or footbridges for accommodating services owned by RailCorp (e.g. high voltage, low voltage, signalling, communications) or services owned by other authorities and utilities (e.g. telephone, water supply, sewer lines, power and gas).

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The designer shall consult the relevant authorities and shall provide special ducts for both current services and future services where appropriate. Services shall be segregated where necessary, e.g. power and signalling.

The location and fixing of such service ducts is to be designed so that future access to the services for maintenance is facilitated and access to the main structure for inspection and maintenance is not impeded.

Service ducts are to be provided within the structure (e.g. under footways), in preference to exposed service lines.

3.8 Safety The design of overbridges and footbridges including the refurbishment of existing structures is to take into account safety considerations for construction and maintenance personnel, and the future users of the structure.

The requirements of the RailCorp Safety Management System, particularly SMS-12-PR-0371 Managing Engineering Design Control, are to be observed and incorporated in all designs.

Designs for overbridges and footbridges shall provide safe access for inspection and maintenance. This may include access steps, ladders, cages, walkways and fixing points.

3.9 Protection of the Environment The design of overbridges and footbridges including the refurbishment of existing structures is to take into account environmental impacts during construction and maintenance activities, with a view to minimising any impacts.

3.10 Heritage Heritage considerations and classifications must be observed in all overbridge and footbridge designs. This may have particular application in circumstances where an existing structure is being refurbished or modified, or where a new structure is being proposed in the vicinity of existing heritage items.

3.11 Design Procedure – New or Infrequently Used Products If any products specified in the design documentation can reasonably be deemed to be new or infrequently used, these must be identified by the designer and referred to the Chief Engineer Civil for approval. The designer must be satisfied that the manufacturer/constructor/maintainer understands any special requirements/practices relating to the product prior to release of the design documentation.

3.12 Nameplates and Plaques All new overbridges and footbridges and bridges that undergo major refurbishment are to be provided with nameplates, indicating the Constructing Authority (e.g. RailCorp) and year of construction. The nameplates will normally be of brass construction and fitted to a suitable location on the Down side of the bridge (e.g. bridge kerb or balustrading end-post).

3.13 Drawing Standards Construction drawings are to comply with RailCorp’s standard procedures and formats, and are to detail the design loadings, horizontal and vertical clearances, and any other information that is relevant to ensuring that the new structure is constructed and maintained in accordance with the design.

3.14 Construction Design documentation is to identify standards for construction, including construction methods, processes and materials.

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RailCorp has a suite of technical specifications for construction of structures. The specifications are detailed in Engineering Specification SPC 301 “Structures Construction” and are to be incorporated in the design and construction documentation of overbridges and footbridges.

Design documentation shall include relevant references for material testing and testing of welds.

The design of new overbridges and footbridges and the refurbishment of existing structures is to take into account construction constraints, particularly under live particularly live road and rail operating conditions and track possession constraints.

3.15 Maintenance The design of overbridges and footbridges including the refurbishment of existing structures is to take into account the ability to access components for inspection and maintenance purposes.

Components, materials and finishes should be chosen to minimise future maintenance.

Maintenance requirements are to be specified in all design documentation for structures. Requirements are to include examination tasks and frequencies, damage limits, and repair standards. In most cases, ESC 100 “Civil Technical Maintenance Plan” and ESC 302 “Defect Limits” will apply. However site specific maintenance requirements may need to be provided.

3.16 Advertising Signs Design loadings for advertising signs shall be in accordance with relevant Australian Standards.

The bridge shall be assessed for the structural capacity to withstand the advertising sign design loadings.

Fixing details shall be in accordance with design codes and practices. They shall not impact on the structural integrity of the bridge. They shall only be made into existing structural members with the approval of the Chief Engineer, Civil. They shall not create an obstruction that causes water to pond or debris to accumulate on the bridge structure.

Fixings and ladders for the sign shall not impinge on the clear walking space of footbridges and pedestrian walkways.

Signs and fixings shall not prevent access for inspection and maintenance of the bridge, including the structure immediately behind the sign.

4 Design Criteria

4.1 Overbridges Designs shall comply with AS 5100. The relevant road authority and other involved parties are to be consulted in order to ascertain the proposed usage and loading requirements for the structure.

4.2 Footbridges Designs including ramps and stepways shall comply with AS 5100 and other relevant Australian and RailCorp Standards.

Designs are to take into account dynamics associated with crowd loading from rail patrons and the general public at stations and at other locations where required based on usage.

4.3 Widening or Extending of Existing Bridges Design loads for widening or extending existing bridges shall be as above, unless waivers have been approved by the Chief Engineer, Civil.

It may be permissible to design the extensions for a reduced traffic loading than that prescribed in AS 5100 if the live load design of the existing bridge structure is below AS 5100. However,

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overbridge extensions shall be designed for a minimum loading of T44. Designs for loading less than AS 5100 shall be approved by the road authority and the Chief Engineer, Civil.

4.4 Seismic Loading The class of bridge for seismic loading in accordance with AS 5100.2 Table 14.3.1 Bridge Earthquake Design Category is Type III, i.e. essential to post-earthquake recovery.

5 Bearings and Deck Joints Bearings and deck joints shall be designed in accordance with AS 5100.4 “Bridge design, Part 4: Bearings and deck joints”.

The design loads shall be in accordance with AS 5100.2 “Bridge design, Part 2: Design loads”.

Bearings and joints shall be designed to provide sufficient access for the inspection, maintenance and replacement of the bearings and joints.

The minimum vertical distance between the underside of the main beams and the bearing shelf shall be 500 mm.

Jacking points shall be provided on the bearing shelf.

6 Configuration Requirements

6.1 Bridge Decks New bridge decks shall be structurally continuous without gaps or open joints to prevent matter and debris penetrating the deck within the spans. Where precast beams with gaps are used, there shall be a continuous deck slab rather than joints at the top surface.

Bridge decks installed during refurbishment/replacement of existing bridges shall wherever possible be structurally continuous.

6.2 Overhead Wiring Fittings Overhead wiring fittings shall not be attached to a bridge unless this is not practicable due to the width of the bridge or the design of the overhead wiring system.

6.3 Stepways Stepway riser and tread dimensions for footbridges are to be 150 mm and 300 mm respectively.

Stepway risers are to be closed in to prevent visibility from beneath the structure.

6.4 Barriers, Safety Screens and Protection Screens 6.4.1 Definitions

Barriers are defined as the fence or walls along the sides of overbridges and footbridges, installed to protect road vehicles, cyclists and pedestrians from falling over the edge of the bridge.

Safety screens are defined as impenetrable barriers intended to prevent persons from contacting 1500 volt DC equipment and to protect 1500 V DC equipment from damage.

Protection screens are defined as screens installed on overbridges and footbridges to prevent access to a safety screen and to restrict objects from falling or being thrown onto the track below. S

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6.4.2 Barriers Bridge barriers for new structures and major refurbishments are to be designed in accordance with AS 5100. The barriers provided above the rail corridor shall be at least medium performance level and should be subject to a risk assessment to determine whether a higher performance level is required.

The approach barriers to new, extended or refurbished overbridges and footbridges must also comply with AS 5100.

Pedestrian barriers and balustrading for new structures and major refurbishments are to be a minimum height of 1200 mm. Where the bridge provides access to a railway station, the requirements of the RailCorp Station Design Guide are to be accommodated.

6.4.3 Safety screens Safety screens shall be installed to prevent contact with the 1500 V overhead wiring.

For new and refurbished bridges, vertical safety screens shall be used. They shall be insulated from the bridge structure.

Where horizontal screens are attached to the face of the structure on existing bridges, the screen shall be bonded via a spark gap.

Design and construction requirements are detailed in RailCorp Electrical Standard EP 08 00 00 07 SP “Safety Screens for Bridges over 1500 V OHW Equipment”.

Safety screening is also to be provided to footbridge landings, ramps and stairs where they are adjacent to the overhead wiring.

6.4.4 Protection screens Prevention of objects falling or being thrown from overbridges and footbridges shall be achieved by the provision of one of the protection measures listed in AS 5100, including full enclosure (footbridges), provision of solid opaque walls with a minimum height of 2.4 metres, or the provision of protection screens.

Protection measures shall be installed on all new overbridges and footbridges in the 1500V (electrified) area. They are also to be installed when a bridge or bridge barrier is being replaced.

For the purposes of this section, the edge of the travelling lanes (refer to AS 5100) is Normal Structure Gauge as defined in RailCorp Engineering Standard ESC 215 Transit Space.

Attention is to be paid when designing protection screens to the detail at the ends (e.g. adjacent to the abutments), to prevent persons gaining access to the outside of the bridge and then the overhead wiring.

For other existing overbridges and footbridges, the requirement for protection screens is to be assessed on the basis of a risk assessment in accordance with RailCorp’s Safety Management System. The assessment should include a review of incident data. Reference should also be made to RTA Technical Direction TD 2002/RS02 “Policy for Safety Screening of Bridges” for guidance on the risk assessment.

Where required to be installed, protection screens are to be designed in accordance with AS 5100. The design should provide a balance between functionality, aesthetics, effectiveness and value for money, giving due consideration to the following factors:

− Safety for train users/operators: the ability of the screen to prevent objects from being thrown onto the track;

− General safety and train operation: the ability of the screen to prevent trespassers from climbing onto safety screens, thereby endangering their lives and impacting on train traffic;

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− Pedestrian amenity: the ability of the screen material and design to provide adequate ventilation, suitable acoustics, light to the inside of the bridge, and views through the screen to the surrounding environment;

− Visual aesthetics: the likely visual impact of the screened bridge as viewed by people in the surrounding area;

− Sharp edges: the design shall minimise any exposed sharp edges on the pedestrian side;

− Modular construction: barrier screens should be designed to be modular, so that individual panels can be replaced;

− Costs: the likely construction and maintenance costs, including initial, ongoing, life span, vandal damage, and graffiti.

6.5 Drainage A drainage system shall be provided on all overbridges and footbridges. The water shall be directed away from platforms and other RailCorp infrastructure and shall not discharge onto the rail corridor. The drainage system shall be cleanable. The minimum pipe size shall be 225 mm diameter.

7 Miscellaneous Design Requirements

7.1 Electrical Requirements 7.1.1 Earthing and Bonding

Designs shall provide for earthing and bonding of metallic components on the bridge to mitigate touch potential hazards and corrosion of steel.

The design strategy should be to “design out” earthing and bonding issues by separation and isolation of metallic structures. Where this is not possible, the design shall achieve an appropriate balance of the risks associated with touch potentials and corrosion due to stray currents.

Design requirements are:

− Steel and concrete bridges shall be insulated from earth.

− Overhead wiring structures on bridges shall be bonded via a spark gap.

− Overhead wiring fittings attached to a bridge shall have tertiary insulation and be bonded via a spark gap.

− Vertical safety screens shall be insulated from the bridge structure.

− Horizontal safety screens shall be insulated from the bridge structure and shall be bonded via a spark gap.

− Other metallic components such as fences, balustrades, handrails, protection screens and traffic barriers shall be insulated from the bridge structure.

− Utility services, such as water, gas, communications and lights, shall be insulated from the bridge structure. There shall be a 2 metre separation between light columns and any other metallic structure.

Insulation panels may be required in fences and vertical safety screens to prevent transfer of potential.

Electrical requirements are specified in RailCorp Electrical Engineering Standards for Earthing, Bonding and Electrolysis, in particular:

− EP 08 00 00 07 SP “Safety Screens for Bridges over 1500V OHW Equipment”

− EP 12 10 00 21 SP “Low Voltage Installations Earthing”

− EP 12 20 00 01 SP “Bonding of Overhead Wiring Structures to Rail” and

− EP 12 30 00 01 SP “Electrolysis from Stray DC Current”.

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7.1.2 Clearances to Electrical Services and Equipment Electrical services within the rail corridor may include aerial lines, 1500V dc overhead traction wiring and equipment and exposed low voltage equipment.

Bridges are to be designed and constructed to ensure that minimum clearances are observed to all electrical power lines and equipment, as laid down within the Australian Standards, the regulations of the relevant electrical authorities and RailCorp’s Electrical Standards.

Where high voltage aerial lines are located above the bridge, measures shall be taken to ensure that:

− Buildings such as booking office and retail outlets are not located underneath the high voltage aerial lines (refer to EP 12 10 00 22 SP “Buildings and Structures Under Overhead Lines”); and

− The risk of transferred potential associated with fallen conductors is mitigated.

The deck structure in the vicinity of overhead wiring shall be designed to provide an impenetrable barrier intended to prevent persons from contacting 1500V dc equipment.

7.1.3 Provision for Attachment of Overhead Wiring The bridge structure shall be configured so that overhead wiring support and registration equipment can be attached where necessary (requirement depends on the width of the bridge).

7.2 Fire Rating As a minimum, the fire resistance level of footbridges (for life safety purposes and where not associated with a railway station) should be 30 minutes. An extra level of fire rating may be required for property protection, and this should be agreed with the Chief Engineer Civil.

For footbridges providing access to railway stations, the minimum fire resistance level should be 2 hours.

The fire rating criteria apply to the structural elements of the bridge above the tracks excluding other spans, stairs and ramps not above the track.

7.3 Formwork Permanent formwork located above 1500 V overhead wiring must be of a non-corrosive and non-conductive material, to eliminate the potential safety risk of decay and subsequent contact with the wiring.

No "Bondek" or other similar steel permanent formwork is to be utilised on the span above electrified track or track that may be electrified during the expected life of the structure (approximately 100 years).

Acceptable products for permanent formwork above electrified tracks include fibreglass.

7.4 Deck sheeting Asbestos/fibrous cement deck sheeting is not permitted on new footbridges and is to be progressively replaced on existing structures.

7.5 Bird Nesting Design features such as spikes may be required to prevent birds nesting on the bridge structure. S

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8 Collision Protection

8.1 General The design of piers or columns supporting overbridges or footbridges within the rail corridor is to comply with the provisions for collision protection and loading in AS 5100.

New structures shall be designed with a clear span between abutments unless supports are on platforms that comply with current RailCorp standards.

The prime requirement is to protect the piers and columns against damage from a derailed train, which in turn could result in collapse of the structure onto the train.

Similarly, piers and columns located next to roadways should be protected against impact from road vehicles.

If additional rail tracks are being installed that will involve an existing overbridge or footbridge being modified or extended and an existing support being converted to a common support, provision is to be made for collision loading from a derailed train on both sides of the bridge support.

8.2 Lift Structures The design of lift wells and lift shafts is to include requirements for train collision loads.

Lift structures may require to be installed adjacent to the track to provide easy access for rail passengers. At some locations they may be constructed close to the track and at track level. Hence the platform will not protect the lift from train collision.

If the lift structure supports the bridge, it shall be treated the same as a pier or column and the requirements of this standard for collision protection apply.

If the lift structure does not support the bridge, is located at track level, is within 10 metres of the track centreline and is not protected by an adjacent platform or other structure that complies with the collision loads in AS 5100, it shall be designed for the minimum collision load of 500 kN in accordance with Clause 10.4.4 of AS 5100.2.

8.3 Location of Piers, Columns and Deflection Walls The minimum clearance to track centre line from any pier, column or deflection wall shall be as specified in ESC 215 “Transit Space”.

A pier or column shall not be located between tracks except on platforms. Variation to this may only be approved by the Chief Engineer Civil.

When designing major refurbishment, replacement of a structure or construction of a new structure, the superstructure shall have structural redundancy to prevent collapse of the structure under impact loads.

8.4 Design Loading All piers or columns supporting a new overbridge or footbridge within the rail corridor shall be designed in accordance with the provisions of AS 5100. The same requirements apply to major refurbishment works including any alterations to the piers or columns, increases in loads on the structure or expansion of the structure.

Clause 10.4.3 of AS 5100.2 need not apply to piers and columns located on platforms provided all of the following conditions are satisfied:

− Platforms are earth-filled and designed in accordance with relevant RailCorp standard. Note that earth-filled platforms will provide full dispensation in Section 10.4.3 of AS 5100.2. Suspended platforms will require to be assessed by rigorous analysis to demonstrate that the

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platform can provide an adequate level of protection to the pier or column when the platform is subject to design loading;

− Pier or column transverse location (with respect to track) is in accordance with RailCorp Engineering Standard ESC 215 “Transit Space” (e.g. in excess of 4.3 m from centreline of track);

− Pier or column longitudinal location (with respect to track) is in excess of 20 m from end of ramped platform, or is in excess of 2.6 m from end of vertical (non-ramped) platform.

All piers and columns including those on platforms as described above, must satisfy Clause 10.4.4 of AS 5100.2 for the minimum design load. Platforms shall not be assumed to provide a degree of protection to permit reduction of the 500 kN collision load.

For temporary structures (less than 12 months) and refurbishment of existing structures, a risk assessment should be undertaken to determine whether any relaxation to the load requirements of AS 5100 can be made.

The risk assessment is to be performed in accordance with RailCorp’s Safety Management System. The analysis should consider the following criteria:

− Site condition, cutting, embankment etc.

− Derailment history

− Type of structure, i.e. potential for collapse damage to trains

− Track geometry

− Track speed

− Type of rolling stock

− Future usage and growth in patronage

The results of the risk analysis will determine the category of collision loading in AS 5100 that is to be applied to a support. The risk ranking determined from the risk analysis shall be equated to a loading requirement from AS 5100 as tabulated in Table 8.3 below:

RailCorp Level 2 Safety Risk Matrix

Ranking AS 5100 Collision Loading Requirements

A All requirements of AS 5100.2 clause 10.4.3, clause 10.4.4, clause 10.4.5 and clause 10.4.6.

B AS 5100.2 clause 10.4.3 (using loading for between 10m and 20m from centre line of track), clause 10.4.4, clause 10.4.5 and clause 10.4.6.

C AS 5100.2 clause 10.4.4, clause 10.4.5 and clause 10.4.6.

D AS 5100.2 clause 10.4.4 and clause 10.4.6.

Table 1

The use of lower order protection devices such as earth mounds, gabions or guard rails etc. may be used in the risk analysis to reduce the risk ranking if approval is obtained from the Chief Engineer Civil.

8.5 Structural Configuration Piers or columns may be designed to withstand the load criteria stipulated in AS 5100 by configuring either as:

− individual units

− in combination with deflection walls, or

− solely reliant on deflection walls

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Piers, columns and deflection walls shall comply with the structural configuration and geometric requirements of AS 5100.1. In addition, piers, deflection walls or the first column of a group shall have the leading faces rounded or vee-shaped.

In the case of retrofitting a deflection wall to an existing vulnerable pier or column, as well as infill walls, end walls shall extend parallel to the track, 3 metres on the approach side of the pier or column.

8.6 Guard Rails 8.6.1 Functional Purpose

The prime purpose of guard rails on rail tracks is to keep derailed or derailing bogies/ wheels tracked parallel to and in close proximity to the running rails. In the case of an overbridge or footbridge, the guard rails afford a level of protection to an adjacent pier or abutment.

8.6.2 Configuration Where guard rails are determined to be appropriate for providing protection to vulnerable supports of overbridges and footbridges, they are to be installed in accordance with the following requirements:

− Guard rail shall be new rail manufactured to AS 1085.1 or recycled rail Category 1 (White rail) in accordance with ESC 220 “Rail and Rail Joints”.

− Guard rail section is to be the same as the running rail or one section size less than the running rail.

− Top of guard rail is to be no higher than the adjacent running rail and no more than 50 mm below the running rail.

− Each guard rail is to be plated and fastened on both sides to every sleeper.

− Guard rails are to extend parallel for a minimum 20 metres in advance of the vulnerable support on the train approach side.

− Guard rails are to extend parallel for a minimum of 3 metres beyond the vulnerable support on the train departure side.

− A tapered nose section (“vee”), minimum 3.6 metres long, is to be installed on the train approach side of the guard rail. The nose of the vee shall be bolted.

− Where rail traffic is bi-directional, the guard rail is to extend 20 metres beyond the vulnerable support on both approach and departure sides

− Where rail traffic is bi-directional, the tapered nose section is to be installed on both sides.

− The clearance between the gauge face of the running rail and adjacent face of guard rail is to be 380mm.

− Block-out holes for guard rail fastenings in concrete sleepers shall be grouted with an approved high strength grout.

For fixing details, dimensional set-out and componentry detail and sizes, standard guard rail drawings are available as follows:

785-568 Bridge guard rail Ballast top bridge Arrangement for concrete sleepered track

785-569 Bridge guard rails Details of concrete guard rail sleepers Concrete sleepered track

785-570 Bridge guard rails Ballast / Transom top bridge Arrangement for timber sleepered track

785-571 Bridge guard rails Timber sleepered track Details of special plating for tapered nose

8.6.3 Signalling Interface Suitable isolation arrangements are to be made, where required, in track circuited and electrified areas.

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© Rail Corporation Page 16 of 20

The tapered nose section (“Vee”) is to be insulated with an approved component - refer to Figure 1. Generally one insulated joint is satisfactory. This insulation requirement applies to new installations and where refurbishment of the guard rails is undertaken.

Figure 1

Where guard rails exceed 50 metres in length, additional insulation and bonding arrangements may be required. Design drawings are to specify that insulation and bonding arrangements shall be in accordance with the requirements of the Chief Engineer Signals. See RailCorp Engineering Standard ESG 100.17 - Signal Design Principles Track Circuits.

8.6.4 Joints in Guard Rails Guard rails on track adjacent to overhead bridge supports may have minimal joints with at least two bolts on each side.

If standard fishplates are used, six bolts are required.

If modified fishplates are used, the four bolts shall all have the nuts on the inside. Fishplates shall be modified by machining, not by oxy-acetylene cutting.

No joints are permitted in the vee.

9 Safety Refuges and Handhold Devices

9.1 Provision of Safe Areas The design of new overbridges and footbridges must make provision for a safe area for infrastructure and other authorised staff to stand during the passage of a train.

A safe area must be provided below an overbridge or footbridge where the abutment or pier wall is longer than 20 metres.

Issued July 2010 2.2 UNCONTROLLED WHEN PRINTED Version

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In lieu of calculating kinematic envelopes, the default clearances to the front of the safe area are:

− 2230 mm on tangent track

− 2500 mm on curved track.

9.2 Locations with Limited Clearances 9.2.1 Clearance less than kinematic + 600 mm:

When the clearance dimension from the track centreline to the overbridge or footbridge is less than kinematic plus 600 mm, refuges are to be provided for retaining walls longer than 20 metres.

9.2.2 Clearance between kinematic + 600 mm and kinematic + 1200 mm When the clearance dimension from the track centreline to the overbridge or footbridge is between kinematic plus 600 mm and kinematic plus 1200 mm, handhold devices as specified in Section 6.6 are to be provided for retaining walls longer than 20 metres.

9.2.3 Limited Clearance Sign Owing to physical constraints, it may not always be possible to provide refuges or handhold devices along new or existing overbridges or footbridges.

Where refuges or handhold devices are required but are not provided, overbridges and footbridges shall have warning signage attached.

Warning signs should be considered for overbridges and footbridges less than 20 metres in length where clearance is less than kinematic plus 1200 mm.

The sign is a warning that there is insufficient clearance to stand safely when trains are passing.

Warning

Limited Clearance

150mm

150mm


9.3 Locations with Adequate Clearances When the clearance dimension from the track centreline to the overbridge or footbridge is greater than kinematic + 1200 mm, no physical protection or signage is required.

9.4 Location of Refuges, Handhold Devices and Signs The spacing of safe areas/ refuges/ handhold devices below an overbridge or footbridge is not to exceed 20 metres. The spacing at each location is to be determined by a risk assessment, taking account of factors such as train speed, available sighting distances, existence of warning light systems.

Refuges/ handhold devices shall be provided on one side only of a single track where there are structures closer than the clearances for safe places on both sides of the track.

Where clearances are restricted on only one side of a single track, refuges/ handhold devices are not required. Signage is required on the side of the obstruction as detailed in 9.2.3.

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Where refuges/ handhold devices are required on multiple tracks, they shall be provided in a staggered pattern on both sides of the track group.

The limited clearance sign is attached to the wall structure so as to be clearly visible to personnel standing on or adjacent to the track. The sign is required at access points to the limited clearance area.

The sign is to be attached at each end of the wall structure and at locations along the structure wall where access is available to the track adjacent to the structure.

If access is only available from the end of the structure, no signs are required along the wall.

If access is continuously available, for instance the structure is on one side only, signs are to be installed at maximum 20 metre intervals along the structure.

9.5 Refuge Details The floor of the refuge is to be at cess level or with a maximum step up above the cess level of 200 mm.

The minimum dimensions of refuges are to be:-

Height: 2000 mm

Width: 1500 mm

Depth: 700 mm

If the refuge is to contain telephones, fire extinguishers or other essential items, the width is to be increased to provide the same clear floor area.

The floor of the refuge is to be level. The refuge is to be kept clear of cables, pipes or other obstructions.

Handrails must be installed in all refuges to assist staff in keeping their balance during the passage of a train.

9.6 Handhold Device Details A schematic layout for a handhold device is shown below.

It comprises two vertical pipe handrails of 40 mm diameter, located 1000 mm apart and each protruding 400 mm from the fixing point on the structure.

The pipes are to be manufactured from galvanised steel.

Each handrail extends vertically from 900 mm above cess level to 1800 mm above cess level.

The horizontal and vertical elements of each handrail are connected by a bend of 200 mm radius.

A level standing area at cess level is to be provided between the handhold devices.

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10 Name Signs

10.1 General Name signs shall be installed on overbridges designated by the Civil Maintenance Engineer.

The name description shall be a readily recognisable name such as Erskineville Road, Pennant Hills Road or Sunnyholt Road.

10.2 Signage Requirements 10.2.1 Type of Signage

Name signs shall be painted using stencils and sprayed directly on the designated overbridges.

Alternative methods of installing signs, including the attachment of a sheet metal sign, may only be used with the approval of the Chief Engineer, Civil

10.2.2 Location For single and double tracks, the signage shall be installed as follows:

− Bridge abutment or wing wall: to the left of the track as seen by the train driver as the train approaches the structure and vertically between 1500 mm and 3500 mm above rail, or

Handhold Device

400 mm

20 0 m m radius

CE SS LEVEL

900 m m

900 mm 1000 m m

40 mm dia

− Bridge girder, deck or superstructure: to the left of the track as seen by the train driver as the train approaches the structure. The left edge of sign shall not be more than 2000 mm from the centre of the track.

For locations with more than 2 tracks, the sign location shall be determined on a case by case basis with due consideration of train driver angle of vision, predominant track usage, train direction and other site specific factors.

10.2.3 Detail of Text The stenciling details for the text shall be:

− Black lettering

− White background

− Font type in accordance with AS1744 Series E with Medium spacing

− Font size of 160 mm.


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The paint/spray shall be retro reflective.

At locations where vandalism may be an issue, signs are to have an anti-graffitti coating applied.

Typical details are:

E R S K I N E V I L L E R D

N O R T H K I A M A D R

2260

160

2250

160


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