Underwater Examination of Structures · The procedure sets out the requirements for underwater...

Underwater Examination of Structures

T HR CI 12005 PR

Procedure

Version 1.0

Issued date: 20 December 2017

© State of NSW through Transport for NSW 2017

T HR CI 12005 PR Underwater Examination of Structures

Version 1.0 Issued date: 20 December 2017

Important message

This document is one of a set of standards developed solely and specifically for use on Transport Assets (as defined in the Asset Standards Authority Charter). It is not suitable for any other purpose. The copyright and any other intellectual property in this document will at all times remain the property of the State of New South Wales (Transport for NSW). You must not use or adapt this document or rely upon it in any way unless you are providing products or services to a NSW Government agency and that agency has expressly authorised you in writing to do so. If this document forms part of a contract with, or is a condition of approval by a NSW Government agency, use of the document is subject to the terms of the contract or approval. To be clear, the content of this document is not licensed under any Creative Commons Licence. This document may contain third party material. The inclusion of third party material is for illustrative purposes only and does not represent an endorsement by NSW Government of any third party product or service. If you use this document or rely upon it without authorisation under these terms, the State of New South Wales (including Transport for NSW) and its personnel does not accept any liability to you or any other person for any loss, damage, costs and expenses that you or anyone else may suffer or incur from your use and reliance on the content contained in this document. Users should exercise their own skill and care in the use of the document. This document may not be current and is uncontrolled when printed or downloaded. Standards may be accessed from the Asset Standards Authority website at www.asa.transport.nsw.gov.au




Standard governance

Owner: Lead Civil Engineer, Asset Standards Authority

Authoriser: Chief Engineer, Asset Standards Authority

Approver: Executive Director, Asset Standards Authority on behalf of the ASA Configuration Control Board

Document history

Version Summary of changes

1.0 First issue.

For queries regarding this document, please email the ASA at [email protected] or visit www.asa.transport.nsw.gov.au


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



Preface The Asset Standards Authority (ASA) is a key strategic branch of Transport for NSW (TfNSW).

As the network design and standards authority for NSW Transport Assets, as specified in the

ASA Charter, the ASA identifies, selects, develops, publishes, maintains and controls a suite of

requirements documents on behalf of TfNSW, the asset owner.

The ASA deploys TfNSW requirements for asset and safety assurance by creating and

managing TfNSW's governance models, documents and processes. To achieve this, the ASA

focuses on four primary tasks:

• publishing and managing TfNSW's process and requirements documents including TfNSW

plans, standards, manuals and guides

• deploying TfNSW's Authorised Engineering Organisation (AEO) framework

• continuously improving TfNSW’s Asset Management Framework

• collaborating with the Transport cluster and industry through open engagement

The AEO framework authorises engineering organisations to supply and provide asset related

products and services to TfNSW. It works to assure the safety, quality and fitness for purpose of

those products and services over the asset's whole-of-life. AEOs are expected to demonstrate

how they have applied the requirements of ASA documents, including TfNSW plans, standards

and guides, when delivering assets and related services for TfNSW.

Compliance with ASA requirements by itself is not sufficient to ensure satisfactory outcomes for

NSW Transport Assets. The ASA expects that professional judgement be used by competent

personnel when using ASA requirements to produce those outcomes.

About this document

This document details the requirements for undertaking underwater examination of structures

on the TfNSW heavy rail network.

This document was previously issued as T HR CI 12005 ST Underwater Examination of

Structures, version 1.0 in April 2014.

This document has been revised and issued as T HR CI 12005 PR Underwater Examination of

Structures, version 1.0.

T HR CI 12005 PR Underwater Examination of Structures, version 1.0 replaces

T HR CI 12005 ST and includes the following changes:

• deletion of two assets that were vested to Department of Primary Industries – Lands

(ID: N00UB10002ALLT_17.500 and N00UB10002MAIN_58.463)

© State of NSW through Transport for NSW 2017 of 37



• deletion of two assets that were vested to the Australian Rail Track Corporation

(ID: M52UB10087GOOD_10.423 and M50UB10089ALLT_13.991)

• deletion of two assets that did not have underwater elements

(ID: N00UB10002ALLT_115.131 and S00UB10043MAIN_17.815)

• update of Table 2 to reflect the entries as they appear in the Bridge Management System

• conversion of this document from a standard to a procedure

• minor changes and application of current template

• additional requirements around underbridges that require an underwater examination but

may not need a diving team due to limited depth of water

• added a table of additional underbridges (Section A.3)




Table of contents 1. Introduction .............................................................................................................................................. 7

2. Purpose .................................................................................................................................................... 7 2.1. Scope ..................................................................................................................................................... 7 2.2. Application ............................................................................................................................................. 7

3. Reference documents ............................................................................................................................. 8

4. Terms and definitions ............................................................................................................................. 8

5. General requirements ............................................................................................................................. 8 5.1. Structures requiring underwater examination ........................................................................................ 9 5.2. Scope and frequency ............................................................................................................................. 9 5.3. Diver qualifications and equipment ...................................................................................................... 10 5.4. Classification and numbering of bridge elements ................................................................................ 10 5.5. Briefing for dive crew ........................................................................................................................... 11

6. Cleaning marine growth ........................................................................................................................ 12 6.1. High pressure water cleaning (hydro blasting) .................................................................................... 12 6.2. Air chipper cleaning (hydraulic) ........................................................................................................... 13 6.3. Hand cleaning ...................................................................................................................................... 13

7. Identification of defects ........................................................................................................................ 13 7.1. Concrete structures ............................................................................................................................. 14 7.2. Steel structures .................................................................................................................................... 15 7.3. Brickwork, blockwork and masonry ..................................................................................................... 15 7.4. Accuracy of measurements ................................................................................................................. 16 7.5. Stream bed surveys ............................................................................................................................. 16

8. Tender documentation – requests for quotation ............................................................................... 18

9. Reporting and documentation ............................................................................................................. 18 9.1. Urgent items......................................................................................................................................... 19 9.2. Drawings .............................................................................................................................................. 19 9.3. Photographs ........................................................................................................................................ 19 9.4. Video survey ........................................................................................................................................ 19 9.5. Water sampling and analysis ............................................................................................................... 19 9.6. Concrete and masonry core sampling and analysis ............................................................................ 20 9.7. Metal sampling and analysis................................................................................................................ 20 9.8. Appendices .......................................................................................................................................... 20 9.9. Signing of reports ................................................................................................................................. 20

Appendix A Structures requiring underwater examinations (Normative) ........................................ 21 A.1. Underbridges ....................................................................................................................................... 21 A.2. Transmission towers ............................................................................................................................ 23 A.3. Additional structures ............................................................................................................................ 24

Appendix B Sample request for quotation document (Informative).................................................. 28

Appendix C Typical report layout (Informative)................................................................................... 33 © State of NSW through Transport for NSW 2017 of 37



1. Introduction The underwater examination of structures that are permanently submerged in water is an

important component of the examination of civil infrastructure on the Transport for NSW

(TfNSW) heavy rail network.

Principally, structures that require underwater examinations are underbridge substructures (that

is, the abutments and piers).

In addition, certain transmission tower footings on the network also require underwater

examinations.

2. Purpose This document specifies the procedure for the examination of underwater components of

structures on the TfNSW heavy rail network.

2.1. Scope The procedure sets out the requirements for underwater cleaning of marine growth, inspection,

reporting and assessment of components of railway structures that are permanently submerged

in water.

2.2. Application This procedure applies to Authorised Engineering Organisations (AEOs) that are responsible for

the following activities:

• preparation of technical specifications for the underwater examination of structures

• supervision of underwater examination contracts

• assessment of underwater examination reports and the implementation of remedial action

and structural repairs as required

This document applies to the following:

• the AEO maintenance representative – an appropriately experienced and qualified

representative of the AEO’s civil maintenance organisation

• the AEO technical representative – an appropriately experienced and qualified senior

bridges and structures engineer

If, when using the procedure, it is considered that the intent of stated requirements is not clear,

a clarification should be sought from the ASA.




3. Reference documents The following documents are cited in the text. For dated references, only the cited edition

applies. For undated references, the latest edition of the referenced document applies.

Australian standards

AS/NZS 2299.1 Occupational diving operations – Part 1: Standard operational practice

Transport for NSW standards

ESC 300 Structures System

ESC 302 Defect Limits

Legislation

Protection of the Environment Operations Act 1997 (NSW)

Work Health and Safety Regulation 2011 (NSW)

4. Terms and definitions The following terms and definitions apply in this document:

AEO Authorised Engineering Organisation

contractor within the context of this document, a diving company with demonstrated technical

competency in underwater cleaning and inspection

defect deterioration of a component from its original condition

defect category classification of a defect into a category that indicates the severity of the defect

and response time recommended for continuing train operations and engineering assessment

HWL high water level; adopted as the permanent watermark on a structure

NATA National Association of Testing Authorities, Australia

repair priority time frame for the repair of a defect

RFQ request for quotation

TfNSW Transport for NSW

5. General requirements Where the structure is located in tidal water, the submerged area is defined as that area below

the high water level (HWL).

The purpose of an underwater examination of a structure is to do the following:

• review and record the condition of the structure




• identify defects and record any significant change in the condition, loading or

environmental factors that can cause deterioration

• ascertain the rate of deterioration by reference to the previous inspection reports

• identify the category, urgency and estimated cost of any remedial actions required

• provide sufficient information for the safe management of the structure and for any

management action necessary to maintain the safety and serviceability of the structure

• provide information for regulatory reporting, where applicable

5.1. Structures requiring underwater examination Underbridges and transmission tower footings within the TfNSW heavy rail network that require

regular underwater examinations are listed in Appendix A.

There are structures identified in the TFNSW heavy rail network that require underwater

examination; however, a diving examination may not be practical due to limited water depth.

The structures are listed in Section A.3 of Appendix A. The AEO maintenance representative

shall confirm whether a diving examination is required and, where a diving examination is not

warranted, shall develop an appropriate procedure for the examination of structure under water.

5.2. Scope and frequency Underwater examinations shall be undertaken on a six-year cycle, unless otherwise indicated

on the previous report for a particular structure.

A structure may require an examination upon demand following a bridge strike or other ‘force

majeure’. The requirements for such an examination shall be determined in accordance with the

particular circumstances by the AEO maintenance representative.

Each examination requires, but is not limited to, the following activities:

• removal of debris near the structure

• removal of marine growth from the designated parts of the substructure to facilitate

inspection

• provide photographs and diagrams of defects

• conduct a full defect survey of the cleaned surfaces

• preparation of a channel bed profile

• video camera survey

• water sampling

• material sampling




5.3. Diver qualifications and equipment All underwater inspections of the structures listed in Section A.1, Section A.2 and Section A.3 of

Appendix A deemed to require an underwater examination, shall be undertaken by

appropriately qualified divers that meet the requirements of the Work Health Safety Regulation

2011 (NSW), WorkCover NSW and AS/NZS 2299.1 Occupational diving operations – Part 1:

Standard operational practice. All apparatus used and procedures followed during diving shall

comply with the requirements of AS/NZS 2299.1.

A minimum of a three-person crew comprising the dive supervisor, examining diver and

stand-by diver shall be provided during all diving work.

The roles, responsibilities and qualifications of the dive supervisor and the examining diver are

set out in AS/NZS 2299.1. In addition, the examining diver shall have relevant experience in

underwater inspections of bridge substructures.

5.4. Classification and numbering of bridge elements The standard system for the description and numbering of bridge elements is detailed in

ESC 300 Structures System. Specific elements involved in underwater examinations are

illustrated in Figure 1. The pile configuration shall be identified and referenced as shown in

Figure 2 and Figure 3.


Figure 1 - Abutment and pier numbering



Figure 2 - Pile numbering

Figure 3 - Pile face numbering (square and circular)

5.5. Briefing for dive crew The AEO technical representative shall conduct a detailed briefing for all members of the dive

crew prior to the commencement of the underwater examination of underbridges.

The briefing shall cover the following:

• description of the key structural components and materials of the bridge substructure

including discussion of their purpose and criticality

• review of the copy of relevant structural drawings as part of the briefing

• purpose of the examination (refer to Section 5)

• classification and numbering of bridge elements (refer to Section 5.4)

• findings of the previous underwater examination including details of any areas of

deterioration

• details of cleaning requirements (refer to Section 6)

• requirements for identification of defects, and for surveying bed profiles including reduced

level of the selected datum point (refer to Section 7)

• sampling, coring and testing, reporting and documentation requirements (refer to

Section 9)




6. Cleaning marine growth Prior to inspection, crustaceans and other marine growth shall be removed from a

predetermined portion of the substructure components underwater (or within the splash zone).

Cleaning may be carried out using high pressure water, air chipper or by hand cleaning.

In the case of piles, the AEO technical representative shall nominate the number (where

exposed) to be cleaned. Based on the total number of piles per pile group, the number of

nominated piles shall be as nominated in Table 1.

Table 1 – Pile groups – percentage to be cleaned

Number of piles (per group) Percentage of piles (per group to be cleaned)

2 to 5 100%

6 to 20 60%

21 to 40 30%

41 to 60 20%

61 to 80 15%

81 + 10%

The nominated piles shall be cleaned in 200 mm wide strips for the full vertical height of each of

the four faces from high water mark to bed level.

For pilecaps, abutments and piers, a 200 mm wide vertical strip shall be cleaned of all marine

growth on each face of the component from high water mark to bed level. The AEO technical

representative shall confirm the locations.

For historical purposes, the locations of the cleaned parts of the structure shall be documented

in the inspection report and the relevant technical maintenance plan. Over the course of several

inspections, the substructure shall be fully cleaned with different areas cleaned on subsequent

inspections.

6.1. High pressure water cleaning (hydro blasting) High pressure water cleaning technique, as approved by the AEO maintenance representative,

shall be used to remove marine growth and surface contamination to an acceptable level and to

enable fine cracks to be observed without damaging the structure. Fine cracks are defined as

between 0.3 mm and 1.0 mm in width. The water pressure, angle of attack and duration of

surface exposure to high pressure water cleaning shall be carefully controlled at all times to

minimise damage.

The delivered water pressure at the nozzle should be no more than 45 MPa. The angle of the

nozzle to the surface should be approximately zero degrees and the nozzle operated on a

constant front.




If, in the opinion of the diver or cleaner, high-pressure water cleaning is likely to cause section

loss that would damage the substructure element or threaten its integrity, cleaning shall be

stopped and a direction shall be sought from the AEO maintenance representative.

6.2. Air chipper cleaning (hydraulic) Air chipper cleaning can also be used to remove marine growth. The air chipper shall be

handheld equipment that does not damage the integrity of the submerged element and shall be

approved for use by the AEO maintenance representative.

6.3. Hand cleaning Hand cleaning techniques using scrapers and wire brushes may be deemed adequate for

smaller structures or where the thickness of marine growth is small.

7. Identification of defects Each underwater inspection shall identify any of the following defects:

• deformation of the substructure

• parts of the structure that are out of plumb, hogging or sagging, misaligned, buckled or

otherwise distorted

• parts of the submerged structure that are missing

• movement, distortion and condition of connections between elements

• the condition of all foundation bases or piles above bed level

• evidence of foundation movement, sliding or settlement affecting the substructure

• signs of subsidence, heave, misalignment, cracking or movement of the ground

• movement at construction joints such as the interface between pile and cap or piles and

cap, abutment and footing or apron, the pier and cutwater nosing

• excessive wear due to exposure to water

• unsafe access or egress facilities

• significant accidental damage, including that due to bridge strikes from water traffic

• railway materials and other large items of rubbish deposited on the channel bed

• presence of vegetation which might affect the structure

• significant vandalism, graffiti or trespass




• the area and location of any repair, repainting or renewal work carried out since the last

detailed examination, and any work in progress or change of construction not previously

recorded

• defects in monitoring equipment attached to the structure including flood gauges and

fracture tabs (if applicable)

• bed material (approximate grading of sand, silt, clay, gravel or a combination of these)

• flooding or evidence of flooding

• localised bed scouring

• undermining of the substructure

7.1. Concrete structures In general, concrete degrades in the following ways:

• weathering or spalling at exposed faces (particularly within the tidal or splash zone),

resulting from erosion, poor quality concrete, chemical action, water action, corrosion of

reinforcement, cover to reinforcement, crushing at bearing surfaces and drumminess

• cracking from loading changes, including settlement

Based on this, concrete elements and the conditions of any protective treatment shall be

examined.

Staining from corroding reinforcement, spalling and any exposed reinforcement shall be

recorded. The area, depth and location of spalling shall be measured, and the sizes of exposed

reinforcement bars and the amount of corrosion shall be recorded.

Cracks or fractures shall be cleaned, the locations recorded, the widths and depth (where

visible) measured, and evidence of cause and likely age of the fracture logged. The fracture

survey shall continue into the area deemed not normally under water, to give a complete

fracture profile.

Any rust, leaching or other stains, crazing, cracks or honeycombing shall be recorded.

Where it is suspected that the concrete has been affected by loss of cement, chemical attack or

other significant change during placing, curing or, subsequent to construction, evidence of

softening, crumbling or deterioration of the surface shall be recorded.

Concrete surfaces shall be sounded with a hammer to identify the presence and extent of

delamination from reinforcement, drumminess and the potential of areas of spalling and, the

results shall be recorded.

Faulty construction including formwork not fully removed, lack of concrete cover to steelwork,

inadequate curing or poor casting shall be logged.




7.2. Steel structures For the purposes of this section, steel structures shall include steel, wrought iron and cast iron

structures.

In general, steel, in service, deteriorates in the following ways:

• erosion or corrosion at exposed surfaces, and at timber and concrete interfaces

• cracking in members or welds

Based on this, all metalwork shall be examined underwater for corrosion. Any loss of metal due

to corrosion shall be measured, or if this is not reasonably practicable, the reduced dimensions

of metallic elements shall be estimated. Particular attention shall be given to splices in members

and other joints or connections and cracked welds.

Particular attention shall be paid to cracks and graphitic corrosion in cast iron elements. The

range of graphitic corrosion shall be measured and the bed level excavated 100 mm to check

for corrosion covered by bed material. The depth of corrosion shall be measured and an

assessment made of the total area affected by corrosion.

The AEO technical representative shall prepare a documented examination plan to assess

graphitic corrosion effects prior to each underwater examination where steel components will be

examined. This shall take into account any relevant findings of previous examinations and

include requirements for coring of the cast iron elements to assess remaining thickness and

definition of specific areas to be examined and sampled.

New or developing cracks shall be reported immediately to the AEO technical representative.

Cast iron elements shall not be struck to check for integrity.

In addition to general corrosion, particular attention shall be given to the corrosion of rivets and

bolts, identifying any loose connection, any loose or displaced banding on cylinder piers, and

areas in the tidal or splash zone.

The length and orientation of cracks in any metal element shall be recorded.

The condition of the protective treatment (including paintwork and galvanising) shall be

recorded, including any damage caused during the inspection. The date of the last painting, if

known, shall be recorded.

7.3. Brickwork, blockwork and masonry Brickwork, blockwork and masonry shall be examined for open joints looseness, cracks spalling,

bulging, crushing, deterioration of pointing, leaching and stains. The brickwork, blockwork or

masonry shall be sounded with a hammer to identify the presence and extent of internal voids

that may have formed.




The position, extent, width, depth, orientation and total area of defects shall be measured, or

estimated if not practical, and recorded.

7.4. Accuracy of measurements All defects shall be recorded to the following accuracy:

• location and depth of defects below HWL ±200 mm

• crack widths estimated to ±1 mm

• width and depth of spalls measured to ±10 mm

• length of cracks or overall dimensions of deteriorated features measured to ±10 mm

Colour, texture and abnormalities shall also be recorded.

7.5. Stream bed surveys Stream bed surveys shall be undertaken for all underbridges covered by this procedure as part

of each scheduled underwater examination. Stream bed surveys shall be undertaken radially

around piers and at sections across the watercourse. The datum point can be either the

underside of the main girder (if reasonably low), underside of the headstock or top of the pilecap

(if above HWL). The reduced level of the chosen datum shall be clearly identified on the

resulting survey report. This datum shall be used in subsequent surveys.

A minimum of four cross-sections shall be surveyed, one along each face of the bridge, one at

the centre line and a further cross section at approximately 30 m upstream from the bridge.

Where the structure is located within a tidal zone, a fifth cross section should be taken at

approximately 30 m downstream of the structure. Figure 4 shows a plan view of a bridge

structure with cross sectional bed profiling locations.




Figure 4 - Plan view of structure with cross sectional bed profiling locations

Radial levels may also be taken around nominated piers, piles and abutments under permanent

water or within the tidal zone. Four readings shall be taken at each radial, one at the pier face,

the second 1 m away, the third 2 m away and the fourth 3 m away from the pier face. Examples

of radial locations are given in Figure 5.


Figure 5 - Location and numbering of radials around columns and piles



The number of cross-sections, frequency and location of readings and radials shall be agreed

with the AEO technical representative prior to inspection.

The levels of any marks provided on each structure, to facilitate closure in times of flood, shall

be recorded.

The water level at the time of inspection shall be recorded as a vertical distance from the datum

point, expressed in metres to an accuracy of ±100 mm. All sounding measurements shall be

recorded to an accuracy of ±100 mm.

Details and data obtained shall be entered into a spreadsheet with line graphs illustrating cross

section bed profiles and bed depths surrounding pier and abutment elements. A comparison

should be made against the previously recorded bed levels.

Comments should be made as to the profiles and any scouring or undermining to the

substructure, particularly with reference to the previous examinations and any differences.

8. Tender documentation – requests for quotation As stated in Section 5.3, underwater examinations shall be undertaken by qualified divers. If the

AEO does not have appropriately qualified staff, the work shall be undertaken by contract.

A typical technical specification and tender schedule is provided in Appendix B. These

documents should be used as a basis when preparing tender documentation (requests for

quotation) for site specific examinations.

9. Reporting and documentation The results of all underwater inspections shall be recorded in electronic format on the

prescribed inspection report forms. These forms provide for the recording of relevant data and

information on the substructure. The AEO maintenance representative shall ensure that details

of defects, defect categories, actions and repair priorities are entered into the Bridge

Management System.

Within one month of the completion of the underwater inspection of a bridge, the contractor

shall provide a completed underwater inspection report, including the detailed inspection logs,

photographs, sketches, video survey (where applicable) and all other required information for

that bridge. The report shall be submitted to the AEO technical representative, who is required

to analyse the findings, determine any necessary action and assign a repair priority as

appropriate. Repair priorities are detailed in ESC 302 Structures Defect Limits.

A summary of the AEO technical representative’s review shall be attached as a cover sheet to

the original report.

A typical report layout is provided in Appendix C for guidance.




9.1. Urgent items The AEO technical representative shall be informed as soon as possible, prior to submission of

the written report, if the condition of any part of a structure is such that urgent action is required,

or, if urgent action was undertaken.

9.2. Drawings Where defects have been identified, drawings shall be produced and incorporated in the report,

highlighting the extent and locations.

9.3. Photographs Colour photographs shall be provided in all underwater inspection reports. All photographs shall

be numbered, annotated including location and orientation, and dated to identify the particular

item.

Reports shall include sufficient photographs to show or provide clarification of the following:

• any significant defect

• features which the diver and author consider to require amplification

• details or components that are only visible using access equipment provided for the

inspection

• difficulties with access and reason for not examining a particular element of a structure

• limitations – a record shall be made of any items that may not have been photographed

during the inspection as a result of site constraints

9.4. Video survey A full video survey may be required covering all areas and surfaces that were cleaned. The

video survey shall be recorded in real time, with commentary of the diver, over all cleaned parts

of the structure.

9.5. Water sampling and analysis If requested by the AEO technical representative, a representative 1 litre sample water shall be

taken in an uncontaminated container and sent to an approved National Association of Testing

Authorities (NATA) accredited laboratory for chemical analysis. The results including

conductivity, pH value and the amount of chlorides, sulfates and sodium shall be covered in the

report.




9.6. Concrete and masonry core sampling and analysis The AEO technical representative may require concrete cores to be taken for testing. The cores

shall be sent to a NATA laboratory for analysis and the results included in the report.

9.7. Metal sampling and analysis The AEO technical representative may require metallic materials to be tested, in which case the

elements, locations and dimensions shall be nominated. The samples shall be sent to a NATA

laboratory for analysis and the results included in the report.

9.8. Appendices For all underwater inspections, the following documents should be included as appendices:

• copies of diver’s logs

• a record of all operations on site, times and depth under water and details of the persons

performing the various roles

• any problems encountered, keys required and permission to access land

9.9. Signing of reports The front page summary of each report shall be signed and dated by the AEO technical

representative. Signatures shall be manuscript on hard copies of the reports.

If a report requires amendment after it has been issued, the report shall be reissued and clearly

identified as a revision, superseding the previous report. The amended report shall be subject to

review and signature as for an original report.




Appendix A Structures requiring underwater examinations (Normative) Structures within the TfNSW heavy rail network that require underwater examinations are provided in Section A.1 and Section A.2.

Section A.3 contains structures that require an underwater examination; however, a diving examination may not be practical due to limited water depth.

A.1. Underbridges Table 2 provides the list of underbridges, along with their details, that require underwater examination. The data in Table 2 was extracted from the TfNSW

Bridge Management System (July 2016).

The attributes may need to be matched against the current TfNSW Enterprise Asset Management System.

The AEO maintenance representative shall comply with the requirements set out in Section 5 of this standard.

Table 2 – Structures that require underwater examination

Route Discrete Km Equipment Description 2 Equipment Number EGI

I00 7.003 TEMPE - COOKS RIVER (LOCS) UndBr 000000111856 PW411005

I00 7.006 TEMPE - COOKS RIVER (MAIN) UndBr 000000111857 PW411005

I00 19.929 COMO - GEORGES RIVER UndBr 000000111874 PW411003

I00 98.509 YALLAH - DUCK Ck UndBr 000000015884 PW411003

I00 101.100 ALBION PARK - MACQUARIE RIVULET UndBr 000000015892 PW411003

I00 112.468 MINNAMURRA - MINNAMURRA RIVER UndBr 000000015931 PW411005

I10 86.807 LYSAGHTS - ALLENS Ck UndBr 000000016088 PW411003

M13 23.365 RYDALMERE - PARRAMATTA RVR UndBr 000000093080 PW411005

M17 53.250 MULGRAVE - SOUTH Ck UndBr 000000093447 PW411005

M24 10.423 CANTERBURY - COOKS RIVER/CHARLES St UndBr 000000180438 PW411005




Route Discrete Km Equipment Description 2 Equipment Number EGI

M25 18.370 RIVERWOOD-SALT PAN Ck-DN TRACKS-UnderBr 000000492326 PW411003

M25 18.387 RIVERWOOD-SALT PAN Ck-UP TRACKS-UnderBr 000000180462 PW411005

M25 24.357 EAST HILLS-GEORGES Riv/HLDrive UnderBr 000000180491 PW411003

M25 25.638 HOLSWORTHY - WILLIAMS Ck UndBr 000000180492 PW411003

M25 30.722 GLENFIELD - GEORGES RIVER WEST UndBr 000000180495 PW411003

N00 17.500 MEADOWBANK-PARRAMATTA RIVER UndBr 000000010117 PW411005

N00 58.463 HAWKESBURY RIVER - HAWKESBURY RIVER UndBr 000000235308 PW41100600

N00 73.524 WOY WOY - PARKS BAY UndBr 000000051897 PW411003

N00 79.832 GOS-BROAD/BRIS WATER-ABUTS+PIERS NearBr TBA PW410601

N00 79.844 GOSFORD - BROADWATER/BRISBANE WATER UndBr 000000052034 PW411003

N00 96.802 TUGGERAH - OURIMBAH Ck/CHITTAWAY Rd UndBr 000000052226 PW411005

N00 100.480 WYONG - WYONG Ck/TACOMA Rd UndBr 000000053349 PW411005

N00 110.352 WARNERVALE-WALLARAH Ck UndBr_HTG_4801831 000000052360 PW411003

N00 110.359 WARNERVALE-WALLARAH CK-OLD PIERS NearBr_HTG_4801831 000000577433 PW410601

N00 127.025 DORA CREEK - DORA Ck UndBr 000000052583 PW411005

N00 150.423 COCKLE CREEK - COCKLE Ck UndBr 000000052998 PW411005

N00 150.437 COCKLE CK-COCKLE CK-ABUTS+PIERS NearBr TBA PW410601

W00 56.371 EMU PLAINS - NEPEAN RVR UndBr 000000093520 PW41100600




A.2. Transmission towers Footings for the SRA pole numbers 16, 20 to 24, 28, 31, 32, 34 to 36, 38, 42 to 44, 47, 55 and

57 between Hawkesbury River and Woy Woy beside the Main Northern Line between

61.197 km and 65.597 km, require underwater examination.




A.3. Additional structures Table 3 provides the list of underbridges, along with their details, that require underwater examination.

The data in Table 3 was extracted from the TfNSW Bridge Management System (November 2017) and may not list all of the structures.

The attributes may need to be matched against the current TfNSW Enterprise Asset Management System.

The AEO maintenance representative shall comply with the requirements set out in Section 5 of this procedure.

Table 3 – Additional structures requiring underwater examination

Route Discrete Km Equipment Description 2

Equipment Number EGI

I00 70.552 THIRROUL - HEWITTS CREEK UndBr 000000015771 PW411001

I00 72.300 BULLI - WHARTONS Crk UndBr 000000015782 PW411001

I00 74.761 WOONONA - UndBr (Unnamed Ck) 000000015793 PW411001

I00 75.257 BELLAMBI - UndBr 000000015794 PW411001

I00 77.454 CORRIMAL - TOWRADGI Ck UndBr 000000015802 PW411001

I00 77.734 TOWRADGI - UndBr (Unknown Crossing) 000000015803 PW411001

I00 78.348 TOWRADGI - UndBr (Unnamed Ck) 000000015805 PW411001

I00 79.015 FAIRY MEADOW - UndBr (Unnamed Ck) 000000015807 PW411001

I00 79.683 FAIRY MEADOW - CABBAGE TREE CREEK UndBr 000000015810 PW411001

I00 80.153 FAIRY MEADOW - UndBr (Unknown Crossing) 000000015812 PW411001

I00 80.733 NORTH WOLLONGONG - UndBr 000000015814 PW411001

I00 86.465 UNANDERRA - AMERICAN Crk (UPMN) UndBr 000000015841 PW411001

I00 86.466 UNANDERRA - AMERICAN Crk (DNMN) UndBr 000000579621 PW411001

I00 91.204 KEMBLA GRANGE - UNNAMED Ck UndBr 000000015856 PW411001 © State of NSW through Transport for NSW 2017 of 37





I00 91.451 KEMBLA GRANGE - UNNAMED UndBr 000000015857 PW411001

I00 93.161 KEMBLA GRANGE - MULLET CREEK UndBr 000000015862 PW411002

I00 118.002 BOMBO - SPRING CREEK UndBr 000000015950 PW411001

I00 119.940 KIAMA - FARMER St UndBr 000000015957 PW411001

I00 121.611 KIAMA - UndBr (UNNAMED Ck) 000000015962 PW411001

I00 125.813 OMEGA - NTH WEST ARM WERRI LAGOON UndBr 000000015981 PW411001

I00 126.053 OMEGA - WEST ARM WERRI LAGOON UndBr 000000015982 PW411001

I00 126.259 OMEGA - FLAT FLOOD Plain UndBr 000000015983 PW411001

I00 126.463 OMEGA - OOAREE Creek UndBr 000000015984 PW411001

I00 126.630 OMEGA-Ck.STH WEST ARM WERRI LAGOON UndBr 000000015985 PW411001

I00 132.239 GERRINGONG - CROOKED CK Trib UndBr 000000016009 PW411001

I00 135.771 GERRINGONG - WATERWAY UndBr 000000016015 PW411001

I00 139.338 BERRY - BROUGHTON Creek UndBr 000000016027 PW411004

I00 140.220 BERRY - BROUGHTON MILL Creek UndBr 000000016030 PW411001

I00 140.636 BERRY - CAPEL Crk UndBr 000000016032 PW411001

I00 143.959 BERRY - FLYING FOX Creek UndBr 000000016040 PW411001

I10 86.392 LYSAGHTS - UndBr 000000016086 PW411001

I10 87.749 CRINGILA - UndBr 000000016097 PW411001

M00 20.458 CLYDE - Duck River NearBr 000000092935 PW410601

M00 20.990 GRANVILLE - DUCK CREEK UndBr 000000092955 PW411001

M01 2.743 Circular Qy-Rd Ped Stn UBr_HRTG_4801109 000000177414 PW411004

M13 21.374 ROSEHILL - DUCK CREEK UndBr 000000152031 PW411001

M13 21.641 ROSEHILL - ABECKETTS Ck UndBr 000000092993 PW411001 © State of NSW through Transport for NSW 2017 of 37





M16 28.473 FAIRFIELD - PROSPECT Crk UndBr 000000180424 PW411001

M16 28.538 FAIRFIELD - THE HORSLEY Dr OvrBr 000000180304 PW410801

M16 30.802 CANLEY VALE - ORPHAN SCHOOL Crk UndBr 000000180427 PW411001

M17 36.881 MARAYONG - BREAKFAST Crk UndBr 000000093914 PW411001

M17 40.910 QUAKERS HILL-UNNAMED WATERWAY B UndBr 000000492016 PW411001

M25 9.241 TURRELLA-BARDWELL Ck(DN TRACKS) UnderBr 000000234941 PW411001

M25 9.242 TURRELLA-BARDWELL Ck(UP TRACKS) UnderBr 000000516981 PW411001

N00 63.328 WONDABYNE - UndBr 000000051783 PW411001

N00 66.385 WONDABYNE - MULLET Crk UndBr 000000051848 PW411001

N00 70.332 WOY WOY-UNNAMED TIDAL CREEK UndBr 000000054952 PW411003

N00 91.501 OURIMBAH - DOG TRAP GULLY UndBr 000000052172 PW411001

N00 93.921 OURIMBAH-CHITTAWAY Ck/TURPENTINE RdUndBr 000000052199 PW411001

N00 98.704 TUGGERAH - Crk UndBr 000000052242 PW411001

N00 99.640 TUGGERAH - CREEK UndBr 000000052249 PW411001

N00 99.780 TUGGERAH - STRAIGHT CK. UndBr 000000052253 PW411001

N00 101.793 WYONG - CREEK No.3 UndBr 000000235298 PW411001

N00 103.532 WYONG - CREEK NORTH 1 UndBr 000000235299 PW411001

N00 103.767 WYONG - CREEK NORTH 2 UndBr 000000235300 PW411001

N00 127.769 DORA CREEK-MUDDY LAKE-No.3 CREEK UndBr 000000052595 PW411001

N00 138.710 AWABA - STONY Crk UndBr 000000054760 PW411001

N00 139.185 AWABA - CREEK ONE UndBr 000000052768 PW411001

N00 139.390 AWABA - CREEK TWO UndBr 000000054766 PW411001

N00 139.522 AWABA - CREEK THREE UndBr 000000052775 PW411001 © State of NSW through Transport for NSW 2017 of 37





N00 139.673 AWABA - CREEK FOUR UndBr 000000052781 PW411001

N33 166.074 WICKHAM - COTTAGE Crk 1 UndBr 000000055277 PW411001

N33 166.075 WICKHAM-COTTAGE Crk 1 "DOWN" SIDE NearBr 000000571355 PW410602

N33 166.090 WICKHAM - COTTAGE CREEK UndBr 000000055310 PW411001

N33 166.091 WICKHAM-COTTAGE Crk 2 "DOWN" SIDE NearBr 000000571356 PW410602

S00 26.161 CARRAMAR - PROSPECT Crk UndBr 000000180473 PW411004

S00 42.698 GLENFIELD - BUNBURY CURRAN Crk #1 UndBr 000000180562 PW411001

S00 48.290 MINTO-VIADUCT (BOW BOWING Crk No2) UndBr 000000180566 PW411001

S00 53.622 CAMPBELLTOWN (MAINS) - WATERWAY UndBr 000000180574 PW411001

S00 53.623 CAMPBELLTOWN (PWSD) - WATERWAY UndBr 000000576401 PW411001

W00 45.353 ST MARYS - ROPES CREEK UndBr 000000093372 PW411001




Appendix B Sample request for quotation document (Informative)

The following sample request for quotation (RFQ) provides an example that can be used while

preparing the tender documentation.

PART D Technical specification

D1.0 Location and description of underbridge

Insert a brief description of the bridge to be inspected (location, kilometrage, configuration etc.),

together with photos if available.

D2.0 Extent of work

Insert the proposed scope of work by the contractor, for example:

The works under the contract include the following items which shall be carried out in their

entirety in strict accordance with this specification and to the true intent and purpose of the

conditions of contract:

• prepare and implement site specific safety plan

• prepare and implement site specific environmental management plan in accordance with

all relevant required approvals

• prepare and implement site specific rail safety plan

• provide all site facilities as required

• supply of water and electrical services as required

• provide all plans and logistics and undertake inspection of bridge piers and abutments

permanently underwater including splash zone in accordance with the requirements of this

RFQ document

• clean all nominated piles, pile caps, piers and abutments of crustacean and marine growth

by acceptable methods in accordance with the requirements of RFQ document

• measure and report the depth of bed level at each nominated pier or abutment

• undertake full cross section bed profile of channel bed relative to fixed datum point and

HWL

• video survey log of all nominated piles and submerged sections of all piers and abutments

• remove and dispose of all debris and imported material from site

• full site restoration




• provide a Protection Officer Level 4 during site works (if required) and submission of a rail

safety plan, for approval by the AEO for each site

• prepare and submit report incorporating all field observations and any other works

approved by the AEO maintenance representative

Note 1: No contract work shall commence without the AEO maintenance

representative being present.

Note 2: The contractor shall submit the following documentation and obtain the

approval of the AEO maintenance representative prior to commencing contract

activities on site (including site establishment):

o site specific

o environmental management plan

o rail safety plan

o copies of approvals from all relevant authorities for the above

Note 3: The contractor shall allow two weeks from the date of document submission

for the AEO maintenance representative to grant approval or request changes or

additions to the document.

D3.0 Access to site

In this section describe the means of access to the site and include a map if available.

D4.0 Protection of existing structure

The existing track and bridge or bridges will be required to carry railway traffic throughout the

duration of the works. The existing structure or structures shall not be modified, altered,

undermined or disturbed unless written approval of the AEO maintenance representative is first

obtained. Any work then approved shall only be carried out under the control of the AEO

maintenance representative.

D5.0 Site establishment and amenities

The contractor is responsible for the provision of all site amenities that may be required under

the relevant industrial award and work, health and safety legislation. Site establishment shall be

carried out under and without interference to rail traffic.

D6.0 Rail operations and safeworking

The contractor shall take all necessary precautions while on site to avoid any delay, obstruction

or stoppage to railway traffic. Should any avoidable delay, obstruction or stoppage occur, the

contractor will be held responsible for any costs incurred as a consequence.

The contractor shall comply with the minimum horizontal and vertical clearances from the track

centreline to any plant, equipment or structures, as specified in the special conditions of




contract. It should be noted that the specified horizontal clearances apply at rail level and

above. Below rail level, plant, equipment and structures need only keep clear of existing

structures.

Safeworking personnel will be provided by the AEO maintenance representative during the work

on site, as considered necessary by the AEO maintenance representative. The contractor shall

not proceed until the safeworking personnel are in position and have given permission.

Instructions given by safeworking personnel shall be obeyed promptly by the contractor's

workers at all times.

Crossings on an operating track shall not be permitted.

D7.0 Floods and wet weather

The contractor shall make allowance for the possibility of wet weather and have equipment

available to minimise the effects of wet weather. The AEO maintenance representative may

direct that the work proceeds during wet weather.

D8.0 Protection of the environment

All work shall be carried out in such a manner as to avoid nuisance or damage to the

environment. The contractor shall comply with the requirements of the Protection of the

Environment Operations Act 1997 (NSW). No extensions of time or variation in the schedule of

amounts will be considered due to the requirements of the Act.

The contractor shall plan and carry out the whole of the works to avoid erosion, contamination,

and sedimentation of the site, surrounding country, watercourses and streams.

No noise or smoke or other nuisance, which in the opinion of the AEO maintenance

representative is unnecessary or excessive, shall be permitted by the contractor in the

performance of the works under this contract.

Any damage resulting from the contractor not observing these requirements shall be rectified by

the contractor at their cost.

D9.0 Workers and equipment

All diving work shall be carried out in accordance with the requirements of the Work Health and

Safety Regulation 2011 (NSW) and WorkCover NSW. All workers, apparatus used and

procedures followed during diving shall conform to the requirements of AS/NZS 2299.1.

A minimum of three-person crew comprising the dive supervisor, examining diver and standby

diver shall be provided for all diving work under the contract.

All divers engaged under the contract shall hold the appropriate certificates required under

government regulations.

The role, responsibilities and qualifications of the dive supervisor and the examining diver are

set out in AS/NZS 2299.1. In addition to the requirements set out in AS/NZS 2299.1, the




examining diver shall have relevant experience in underwater inspections of bridge

substructures.

D10.0 Drawings

Insert a list of relevant drawings that will be supplied to the contractor.

The drawings supplied are for reference only and may not represent the true condition or the

configuration of the underbridges. Drawings are located in the Appendix (of the RFQ).

D11.0 Site meeting

The AEO shall conduct a pre-tender site meeting to provide details of the requirements for the

proposed contract services, outline the evaluation criteria and methodology to select the

preferred tenderer and to provide potential tenderers with an opportunity to ask the AEO

questions about the RFQ document and clarify any remaining issues.

Insert the details of the proposed tenderers site meeting.

D12.0 Inspection and cleaning requirements

The inspection and cleaning requirements for this contract are provided in Appendix 1 of this

RFQ document.

D13.0 Reporting requirements

The reporting requirements for this contract are provided in Appendix 2 of this RFQ document.

Appendix 1: Inspection and cleaning requirements

Include the relevant extracts from this procedure for:

• structure classification and numbering (Section 5.4)

• acceptable cleaning methods (Section 6)

• identification of defects (Section 7)

Appendix 2: Reporting requirements

Include the reporting requirements, as extracted from Section 9 of this procedure.

PART B Schedule of amounts

A schedule of amounts should be included in the tender schedules, similar to the example

shown in Table 3.




Table 3 – Example schedule of amounts

No Description Qty Unit Rate (excl GST)

Amount (excl GST)

Min fee

1 Site establishment and dis-establishment (including all necessary approvals from relevant authorities)

Item Item Item

2 Prepare, implement and manage WHS plan

Item Item Item

3 Prepare, implement and manage environment management plan (EMP)

Item Item Item

4 Prepare, implement and manage a site specific rail safety plan

Item Item Item

5 Provision of a Protection Officer Level 4 No. Day

6 Clean crustacean and marine growth on substructure elements by hydro blast cleaning, air chipper cleaning or hand cleaning techniques based on specification

No. Day

7 Inspect all cleaned areas of piers and elements deemed to be permanently underwater for defects, and take photographs where required

No. Day Item

8 Measure and report depths of exposed piles from high water mark to bed level

Item Item Item

9 Undertake full cross section bed profile of channel bed

Item Item Item

10 Video logging of all cleaned elements inspected underwater

Item Item Item

11 Take 1 litre water sample and undertake chemical analysis laboratory test

12 Underwater core sampling of concrete piles and test as per specification, including plugging of holes

No. Each

13 Provision and measurement of ultrasonic metal thickness tester (giving digital readouts) for underwater elements

Item Item Item

14 Standby of site activities under instruction of the AEO maintenance representative

No. hr

15 Prepare and submit a pdf file of a report incorporating all field observations, including photographs of defects, hydro blasting details of procurement and what elements cleaned, a copy of the diver's safe work method statement and risk assessment

Item Item




Appendix C Typical report layout (Informative) The following is a suggested format of a report that can be used for preparing the underwater

examination report:

Underwater Inspection Cover Sheet

Location: Inspection date:

Line: SPN:

Hidden parts not examined:

Reason not inspected:

Bed profile details Yes/No Date of exam Yes/No Date of exam

Review of previous examination profiles

Last exam reviewed Penultimate

exam reviewed -

ITEM

Comments and Recommendations Est. Cost

Urg

ency

Cat

egor

y

Date of next inspection:

Authorised Engineering Organisation:

Name of AEO Technical Representative:

Signature: Date:




Structure location:

Grid reference:

Insert photograph and description Insert photograph and description

Insert map Insert photograph and description




With reference to last report Yes / No Comment

Changes in bed profile Evidence of scour Change of construction Works since last exam

Report summary Add a description of the structure, foundations, depth of water, etc. Include sketches as appropriate Provide comments on marine growth and cleaning undertaken Provide a detailed description of any significant deterioration or defects Provide details of any other key observations Add recommendations

Note: Appendices shall be provided in separate sections

Appendix A:

In this appendix describe the cleaning method, time taken, etc.




Appendix B:

Append the diver’s logs in the following layout:

Contractor’s Name: Location:

Exam date: Pier number: Pile number: Pile type:

SPN: Water visibility Good Average Poor Localised scouring Yes No

Datum: Water quality Good Average Poor Debris present Yes No

Page: Bed material Gravel Rock Sediment Other ______________________________

Chainage (from datum)

Face 01 Face 02 Face 03 Face 04 Refer photo and sketch numbers

Comments

NOTES:

© State of NSW through Transport for NSW of 37



Appendix C:

Append photographs

Appendix D:

Append the risk assessment and safe work method statements

Appendix E:

Append drawings

© State of NSW through Transport for NSW of 37

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