9th Australian Small Bridges Conference 2019
Our accepted abstracts are shown below, except that we also have others where the asset owner still has to supply comment and/or approval. After this has been done these additional accepted abstracts will also be added.
Our 2019 Abstracts and Speakers already include:
Michael Kakulas -2
Principal Bridge Engineer
Nicholas Keage
Senior Bridge Engineer

Nimal Jayasekera
Delivery Manager Structures
Main Roads Western Australia


Debonded link slabs have been successfully used for precast pretensioned Teeroff bridges over many years to provide the continuous running surface of a continuous bridge, but with the simplicity of simply supported spans. The same technique has been utilised to repair Boyup Brook Bridge, a 90 year old 4 span steel beam bridge.

The bridge, constructed in 1929 with steel RSJ beams and timber decking, was widened in 1972 and the deck replaced with a concrete slab made composite with the steel beams with shear connectors. The bridge was designed as simply supported with only a cast-in water stop and sealant to prevent water leaking through the deck at the piers. Over time, the water stop inevitably deteriorated under the constant movement and by 2006 significant water was penetrating the deck causing corrosion of steel girders, steel bearings and connections. After repairing the joints with a rubber membrane proved unsuccessful, a debonded link slab was introduced by breaking out the concrete deck for a defined length over the piers and replacing with a continuous reinforced concrete slab made continuous with the adjacent reinforcement but debonded from the steel beams.

This presentation outlines how the remaining life of an existing steel bridge was extended by applying techniques commonly used for new concrete bridges


Michael Kakulas has over 24 years’ experience in bridge design, focussing primarily on the technical aspects of the business, undertaking Design, Discipline Lead and Design Manager roles on road and bridge infrastructure projects across various contract delivery types, including D&C and Alliance Contracts.
Nicholas Keage is a Chartered Professional Engineer with over 8 years’ experience in the analysis, design and documentation of bridges across Australia. His design experience ranges from award winning architectural pedestrian bridges, through to major highway and rail bridges, including incrementally launched bridges.

Nimal Jayasekera has 33 years of career history as a Civil Engineer with wide range of Design, Construction and Project Management experience in road and bridge projects. After completion of his Master’s Degree in University of New South Wales, he started working for Main Roads Western Australia. He has been working in Structures area for last 21 years delivering major bridge projects in Main Roads WA South West Region and is the Delivery Manager Structures for this region
Maryam Varmazyar
Associate Structural Engineer

The West Gate Tunnel Project is a city-shaping project that will deliver a vital alternative to the West Gate Bridge in Victoria and will provide quicker and safer journeys, and remove thousands of trucks off residential streets. The project will include widening the West Gate Freeway from 8 to 12 lanes and include express lanes between the M80 and the West Gate Bridge, reducing weaving and merging that leads to traffic congestion. A tunnel from the West Gate Freeway to the Maribyrnong River and the Port of Melbourne which will take motorists and trucks underground and off residential streets, providing a more efficient freight route.

A bridge over the Maribyrnong River, linking to an elevated road along Footscray Road is to connect to the northern CBD.

Segmental box girder externally post-tensioned bridges are used in the major section of this project to minimise the construction time, having no disruption at ground level and a high controlled quality and cost savings.

This paper describes the design development process for segmental box girders and the bifurcation spans including the determination of structural form and an extensive finite element analysis for the design of the superstructure to confirm the design assumptions and compares the outcomes of the analysis with the results obtained from the AS5100 and AASHTO


Maryam is an associate bridge/structural design engineer with more than 14 years of experience in designing of bridges and various transportation structures. She received her PhD in structural engineering majored in Structural Health Monitoring from the University of Melbourne in 2013. She has a growing list of publications in both academic and bridge engineering industry. She is enjoying renovating their house on the weekends as well. She is currently working on the detailed design of various packages in the West Gate Tunnel project.
Dr Amit Sagar
Bridge Engineer
Chris Morton, Principal Bridge Engineer, pitt&sherry
Dr Andrew Sonnenberg, National Bridge Engineering Manager, pitt&sherry
Nathan Hadfield, Project Delivery Engineer, City of Knox


A timber pedestrian bridge constructed in 1988 for City of Knox, a Victorian council, as part of a cycleway was destroyed following a fire at a nearby transfer station and recycling facility. The bridge was 30.36m long and 2.4m wide, with 12 equal spans of 2.53m spanning over Blind Creek. Post incident, the bridge was closed and City of Knox engaged pitt&sherry to design a replacement bridge.

Key requirements for the new bridge was to maintain the original alignment, reuse existing concrete footings and use FRP instead of timber. However, the use of FRP proved to be challenging due to limited information available in the Australian standards for FRP design. Hence, an American standard, “Pre-Standard for Load & Resistance Factor Design (LRFD) of Pultruded Fiber Reinforced Polymer (FRP) Structures”, was used as a design guideline.

The new bridge was designed for 5 kPa loading in accordance with the requirements of Australian Standards, AS5100.2-2017. All structural components for the bridge are FRP except pedestrian fencing. Based on the site geotechnical data and structural analysis existing concrete footings could be reused with new connections, thereby maintaining the original alignment and a reduced construction cost.


Amit Sagar is a Bridge Engineer at pitt&sherry based at Melbourne. He joined pitt&sherry as a graduate engineer after completing his PhD in Condition Assessment of deteriorating concrete bridge girders. Since joining pitt&sherry he has designed one road bridge, three pedestrian bridges, three bridge widenings and 50 plus Levels 3 inspection assessments.
Ali Chaboki
Principal Structural Engineer

Open deck bridge designs have the timber sleeper /transoms directly supported by the bridge girders. Due to the lower dead loads of these bridges, they are one of the most popular railway bridges and their maintenance cost is much lower than the ballasted deck bridges. However, in the absence of ballast, more dynamic load transfers into the substructure than for ballast decks and this is why rough riding is a common issue of transom bridges. To deal with this issue and to reduce rough riding, the rail is often at an offset to the bridge girders.

The effect of having the rails offset to the support girders is that it creates both a bending moment and shear in the sleepers/transoms. Also, due to the additional stiffness of these bridges, bearings are more vulnerable compared to ballasted decks. The approach slab also plays a more critical role in the quality of the ride of passenger trains on these bridges.

Due to these factors, special requirements for maintenance and assessment of these bridges have been presented in this paper. 


Ali Chaboki is Principal engineer- structures based at V/line head office-Melbourne. For the past 4 years, he has been working with Network engineering group to maintain and renew a broad range of railway infrastructures including bridges, culverts and tunnels. He holds Bachelors, Masters and PhD degrees in Structural Engineering and has more than 20 years’ experience in infrastructure sector as the designer, design manager and senior engineer
Dayani Kahagala Hewage
Phd Candidate
Western Sydney University
Christophe Camille
PhD Candidate
Western Sydney University

Olivia Mirza, Senior Lecturer, Fidelis Mashiri, Associate Professor and Brendan Kirkland, Lecturer, Western Sydney University
Todd Clarke, Lead Engineer, BarChip Australia

Research about railway bridges often focus on the sleepers which are essential components within the track infrastructure. Indeed, most of these studies reveal that the existing sleepers made of either timber, steel or prestressed concrete are not entirely adequate for modern railway operational conditions.

Transoms (i.e. considered as large sleepers) used on railway bridges have higher design requirements as compared to traditional sleepers on ballasted track since they directly transfer the high static and dynamic loads from the rails to the bridge girders. Concerns related to the sleeper’s material have long been acknowledged by researchers, however their practical replacements with composite alternatives remain fairly limited. Therefore, this research addresses the use of Synthetic Fibre Reinforced Concrete (SFRC) as an alternative and sustainable material for transomsf orf railway bridges.

The research presented herein will focus on the mechanical properties of synthetic fibre reinforcement in concrete subjected to various static and dynamic loadings. More emphasis has been given to the flexural and shear strength characteristics since their associated stresses induced throughout the railway bridge ties (i.e. transoms) are comparatively higher. In addition, the effects of different fibre volume and aspect ratios will be thoroughly compared and discussed. The outcomes generated by the experimental tests are expected to enhance the durability, workability and flexibility of the concrete sleepers in the actual Australian railway track infrastructure


Dayani  is a PhD candidate in Western Sydney University. She has obtained the B.Sc. (Hons) in Civil Engineering from University of Moratuwa in 2012 and MPhil. in Civil Engineering in the same university in 2015.

Christophe Camille is a Phd candidate at western Sydney university. He obtained his Bachelor degree (Hons) in Civil Engineering in 2018 at Western Sydney university, sub-majoring in structures.
Michael Kakulas -1
Principal Bridge Engineer
Nicholas Keage 
Senior Bridge Engineer


Bridges comprising precast Teeroff Beams made continuous offer a number of advantages, and have been used increasingly on projects in Western Australia.

Typical methods of achieving continuity rely on specialised construction techniques (i.e. post tensioning) or extensive formwork in constructing in-situ transverse diaphragms. To maximise the combined benefits of a continuous design and precast Teeroff beams, the design of the bridge, and in particular the stitch detail, needs to be as simple as possible.

On Northlink Central Section, a new method of achieving continuity for the highly skewed multi-span bridges was devised. The design innovatively used the standard Teeroff geometry and a voided end block to construct a cast in-situ continuity stitch without any additional onsite formwork. The geometry of the continuity stitch eliminates the need for couplers in the Teeroff beam, or bars protruding through the stitch formwork.

This paper presents the detail used for Northlink Central Section bridges. The resulting savings in materials, formwork and construction costs are compared to the conventional simply supported alternatives.


Michael Kakulas has over 24 years’ experience in bridge design, focussing primarily on the technical aspects of the business, undertaking Design, Discipline Lead and Design Manager roles on road and bridge infrastructure projects across various contract delivery types, including D&C and Alliance Contracts.

Nicholas Keage is a Chartered Professional Engineer with over 8 years’ experience in the analysis, design and documentation of bridges across Australia. His design experience ranges from award winning architectural pedestrian bridges, through to major highway and rail bridges, including incrementally launched bridges
Prof Sami W Tabsh
Civil Engineering Professor
American University of Sharjah, UAE

Trucks that do not satisfy the legal weight and size limits sometimes need to use a transportation network. The effect of such vehicles on a pavement is not as detrimental as on a bridge. In such cases, the bridges along the route shall be checked to see if the imposed loading on them is structurally acceptable.

The girder distribution factors in the AASHTO LRFD bridge design specifications (2017) cannot be used to evaluate the critical live load effect in individual girders if the truck gauge width is different from 1800 mm. Consideration of the vehicle’s nonstandard gauge width in the structural analysis of an existing bridge can help increase the allowable load.

The objective of this study is to develop simple girder distribution factors for shear and flexure for short slab-on-girder bridges subjected to oversize vehicles.

To develop the distribution factors, 126 bridges having different girder spacing and span length, and subjected to wide trucks were analysed by the finite element method. Findings of the study showed that the relationship between the girder distribution factor and gauge width is more nonlinear in shear than in flexure.


Sami W. Tabsh is Professor of Civil Engineering at the American University of Sharjah, UAE, and former Head of the department (2006-2008). He was previously a faculty member with the University of Houston (1994-1999), Texas, and a Project Engineer for complex structures with Gannett Fleming, Inc. (1990-1994), Harrisburg, Pennsylvania. Dr. Tabsh has a Ph.D. from the University of Michigan and MS from Penn State, both in Civil Engineering. His research interests are in reliability-based code development, bridge structures, and large scale experimental testing. He is a licensed Professional Engineer in the State of Pennsylvania, USA.
Kenny Luu -1
Principal Civil Engineer
Amey Australia

The $1.8billion Western Road Upgrade Project, is one of the largest single investments in arterial roads in Australia to date. The Project will deliver upgrades to eight high-priority arterial roads. As part of the initial rehabilitation scope, the upgrade works on the twin bridges on Geelong Road over Kororoit Creek include:
  • Strengthening the bridges for 0.75SM1600 loading
  • Removing the existing half-joints
  •  Resetting the roller bearings at the abutments
  • Upgrading the existing bridge barrier to current standards 
The existing bridges were constructed in 1956 and are of identical structure form. Each bridge comprises three spans with equal span length of approximately 18.3m. The bridge superstructure is supported on the roller bearings over the abutments and is ‘pinned’ to the piers via cast-in shear dowels, respectively. The western abutment comprises a 7.5m high gravity concrete retaining wall while the eastern abutment comprises a sill beam supported on three reinforced concrete columns, which in turns are founded on pad foundations. The piers are formed by blade walls on pad foundations.

Previous inspections of the sub-structures indicate that both abutments have undergone significant displacement which has resulted in the large rotations in the roller bearings. The subsequent structural assessment identified several deficiencies in the geotechnical capacity of both abutments, which are consistent with the findings of the inspections. Therefore, the western abutment is proposed to be strengthened by two rows of ground anchors, which are to be installed through the abutment retaining wall. The eastern abutment is proposed to be strengthened by making the sill beam structurally connected to the end post barrier piles, thus creating 3D framing action between the elements. This solution also overcomes the constructability challenges due to limited access to the front of the eastern abutment.

The assessment also found that the existing piers have inadequate external stability to accommodate the longitudinal forces due to vehicle braking on the deck or in an event of an earthquake. The removal of the half-joints offers an opportunity to alter the current articulation of the bridges and therefore redistribute the longitudinal forces between the abutments and the piers. The longitudinal forces are proposed to be transferred into the abutments, which will now be adequately strengthened.

The paper will discuss the structural assessment and the subsequent strengthening design of the substructures.


Kenny Luu is a Principal Civil Engineer and a bridge team leader with Amey Australia. He has over 16 years of combined research and industry experience with a strong focus in the concept and detailed design of bridges, earth retaining structures and other civil structures. On the Western Road Upgrade Project, Initial Rehabilitation on Structures, Kenny is the design manager responsible for delivering the assessment and strengthening design of eight existing bridges including the twin bridges on Geelong Road over Kororoit Creek.
Kenny Luu -2
Principal Civil Engineer
Amey Australia

The existing bridges were constructed in 1956 and are of identical structure form. Each bridge comprises three spans with equal span length of approximately 18.3m. The back-span superstructure is made up by six haunched cast-in situ reinforced concrete T-beams, which are extended past the piers to form the cantilevered supports for the central suspended span via the half-joints. The suspended span comprises reinforced concrete encased steel girders made composite with the in-situ concrete deck. The bridge superstructure is supported on the roller bearings over the abutments and is ‘pinned’ to the piers via cast-in shear dowels, respectively.

The structural assessment identified deficiencies in the flexural capacities in the transverse deck slab and in the hogging regions of the main T-beams to support the required 0.75SM1600 loading. The deck slab was also found to be structurally inadequate to accommodate an upgrade of the existing concrete parapets to a compliant medium performance barrier. Furthermore, the removal of the half-joints will result in a significant change in the structural behaviour of the superstructure, which needs to be taken into considerations of the strengthening design.

The paper will discuss the structural assessment and the subsequent strengthening design of the superstructures.


Kenny Luu is a Principal Civil Engineer and a bridge team leader with Amey Australia. He has over 16 years of combined research and industry experience with a strong focus in the concept and detailed design of bridges, earth retaining structures and other civil structures. On the Western Road Upgrade Project, Initial Rehabilitation on Structures, Kenny is the design manager responsible for delivering the assessment and strengthening design of eight existing bridges including the twin bridges on Geelong Road over Kororoit Creek.
Ken Maxwell
Technical Director, Bridges

The three arch bridges that cross Hickson Road at Millers Point in Sydney’s CBD represent an early application of reinforced concrete for large span bridges in NSW.

The bridges were built by the Sydney Harbour Trust and are classified as Monier arches. At the time of their construction, 1910 to 1914, they were noted by Sydney’s Daily Telegraph newspaper as the “largest reinforced concrete bridges in New South Wales”.

Due to predicted ground movements from nearby tunnel and cavern excavation work for the Sydney Metro rapid transit system, the arch bridges were structurally analysed to check their capacity to withstand the anticipated horizontal and vertical movements.

The following paper describes the history of the distinctive Hickson Road arch bridges, together with details of the structural analysis work undertaken. Also, a brief outline is provided on the history of Monier arch bridges in NSW.


Ken Maxwell BE Civil (Hons 1) MES FIEAust has designed over 85 bridges and has been involved in the inspection, assessment, concept design and detailed design of road and railway bridges for over 30 year. Ken is a Fellow of and a Chartered Professional Engineer (Civil and Structural) of The Institution of Engineers, Australia, and a member of the International Association for Bridge and Structural Engineering. He is accredited with Transport for NSW as a Subject Matter Expert (Structural), Australian Rail Track Corporation as Designer/Verifier/Approver of bridge design projects, and to undertake Third Party Works Independent Design Review of bridge design projects on behalf of John Holland Rail.
Hari Pokharel
Associate Technical Director
Arcadis Asia Pacific

The focus of this paper is to explore the requirements for detailing proper reinforcement arrangements at the node of a concrete truss so that controlled performance can be achieved to create elegant concrete truss bridges.

The industry should not discourage adopting suitable concrete truss bridges in new projects after the collapse of a pedestrian bridge at the Florida International University in March 2018


Hari has worked more than 30 years in the civil engineering industry, dedicated his services to major infrastructure projects in Australia and Asia. His core interest remained in the research, design, construction and management of rail and road bridges and associated projects. Core skills include the development of computational analysis, better understanding of concrete material and behaviour of structures made of concrete and active user of special purpose-built software for the analysis of concrete bridges including time dependent construction stage analysis.
Sleiman Mikhael
Technical Director – Civil Structure
Arcadis Australia
Suthan Mohanakumar
Structural Engineer
Arcadis Australia


Prestressed concrete I-girders made composite with cast-in-situ concrete deck had been a standard form of concrete bridge construction in the past for spans exceeding the reach of the reinforced concrete planks. Various international design codes had been used at different times until the first Australian national bridge design code was published in 1953.

A frequent issue related to the longitudinal shear strength adequacy of the composite beams has been identified when carrying out the load rating upgrade of these bridges. The longitudinal shear capacity near the supports at the interface between the cast-in-situ deck and the girder was low when calculated to the current Standard (AS5100.5-2017) although the beams have in many instances adequate capacities in bending and vertical shear to cater for the vehicular loads on the road.

This paper presents a review of the mechanism of failure at the deck-girder interface of the composite section applicable to this sort of construction and factors that contribute to the beam longitudinal shear strength. The review explores the Australian Standard and other International Codes of Practice together with published international studies. Concluding comments will be provided regarding the strength of the existing composite beams.


Sleiman Mikhael has over 30 years’ experience in the design of structural engineering projects over Australia and the Middle East. Sleiman’s skills include design and independent review of a variety of steel and concrete, structures as diverse as the existing viaduct widening of the West Gate Freeway, bridges on the Western Ring Road (Tullamarine – Sydney Rd), Pakenham bypass (3), Calder freeway, bifurcated curved composite steel box bridges on Stafford/Gympie Road on Airport Link (Brisbane) and Don Interchange post tensioned continuous spans concrete box girder in Tasmania. Sleiman was also responsible for the rehabilitation/strengthening design of the Princes steel Bridge in Melbourne (City of Melbourne).
Tahmina Hossain
Senior Structural Engineer - Civil Structures
Arcadis Australia, Melbourne, VIC
Sleiman Mikhael

Technical Director - Civil Structures,
Arcadis Australia, Melbourne, VIC

Suthan Mohanakumar
Structural Engineer,
Arcadis Australia, Melbourne, VIC


The AS5100.5-2017 has introduced a new set of shear and torsion design equations based on the Modified Compression Field Theory (MCFT). The MCFT adopted in this revision is an adaptation of fib Model Code 2010 rules. It is apparent that AS5100.5-2017 shear and torsion formula is incomplete using the general method. The new method is introduced as a result of international shift in shear design practice and is meant to replace the previous semi-empiric formula based on the truss theory adopted in the 2004 version of the Code.

The presented paper gives a critical comparison in the AS5100.5-2017 shear and torsion design provisions with those of other international Standards, mainly the AASHTO and the Canadian Standards. Through a parametric analysis, the authors investigate how each code considers the influence of main variables, which come into play in the beam shear and torsion phenomenon, on the evaluation of the developed capacity. Issues and consequences of mixing actions from one code and resistance from another code are also discussed. The comparison also provides several key considerations for shear and torsion design rules, which is necessary for future revisions to the AS5100.5-2017 code provisions.


Dr. Tahmina Hossain is a Chartered Professional Engineer with over 12 years experience in both structural design and documentation of all forms of bridges across Australia. Her design experience ranges from award winning complex road bridges, through to major highway and rail bridges, including incrementally launched bridges.
Dr Tim Heldt
Chief Technology Leader
Joshua Seskis
Senior Professional Leader


The disciplines of bridge management and Structural Health Monitoring (SHM) are both undergoing rapid development.

This paper summarises some of the key trends in both disciplines, and explores the value proposition for the use of SHM in bridge management currently and in the foreseeable future.

Examples will be discussed to illustrate both poor value propositions and good value propositions for SMH supporting bridge management.

Guidance will be provided suitable workflows to engage structural health monitoring to deliver value for bridge management. Some of the key technology advances (in both fields) will also be discussed to illustrate emerging opportunities for the bridge sector, with a focus on local government application.


Dr.Tim Heldt has over 30 years of experience, and currently leads the Australian Road Research Board (ARRB) structures team to deliver quality consulting and research outcomes in the field of structures, asset management services, and technical evaluation. Tim has specialist knowledge and skills in life extension and risk management using ASISO13822. Coupled with his extensive experience in strategic asset management, due diligence and corporate review of strategy (civil and structures) and structural assessment through testing, Tim has the experience to quantify structural risk.

Joshua Seskis is a lead inspecting engineer who is currently responsible for Level 1 and 2 inspection workshop delivery and managing complex inspections for the team. He has previously conducted inspections on structures, which included provisional accreditation, as part of handover inspections conducted for the Moreton Bay Rail Link, Brisbane. He is also responsible for many of the Level 3 inspections conducted by ARRB. Joshua has also had extensive experience working on project related to heavy vehicle assessments and assessment frameworks.
Chang Liu
Senior Bridge Engineer
John McCafferty
Senior Project Engineer
Fulton Hogan

Robert Murphy
Project Engineer
Fulton Hogan


The M4 Smart Motorway project aims to introduce an Intelligent Transport Systems along the M4 Motorway between Pitt Street overpass at Mays Hill and Russell Street at Lapstone in Sydney. The project length is 34km. One of the requirements of this project is to widen on-ramps including bridges, to improve traffic flow. This includes widening the existing Bridge over Reservoir Road.

The nine metre widening comprises Super-T precast girders supported on new sill beams to emulate a similar structural behavior to the existing bridge. The widening section was made integral with the existing bridge via a longitudinal stitch pour at the deck level and a doweled joint between the existing and new sill beams. The existing Reinforced Soil Walls at both bridge abutments were required to be partially demolished and reconstructed to accommodate the alignment of the bridge widening.

This paper discusses the design elements which were required to widen the bridge structure, with an emphasis on the specific constraints associated with this bridge. The paper also discusses how these constraints were translated to the construction phase with a focus on the innovative solutions for the successful widening of the bridge structure, which carries one of the busiest roads in Sydney. 


Chang Liu Chang is a Senior Bridge Engineer with Arup in Sydney with 9 years of experience covering many technical and non-technical facets of engineering. Chang has a wide range of experience with different clients on projects of varying scope. On the M4 Smart Motorway project, Chang was responsible for the delivery of the widening over Reservoir Road.

Co-Author John McCafferty is a Senior Project Engineer with Fulton Hogan in Sydney with 13 years of experience in the construction of a wide range of civil infrastructure. John has recently completed a range of D&C highway projects including the Gerringong Upgrade and Foxground and Berry Bypass. John is the area manager responsible for the Reservoir Road Ramp upgrade on the M4 Smart Motorway project, which includes ramp widening, basins and the bridge widening.

Co-Author: Robert Murphy is a Project Engineer for Fulton Hogan and has been with the company for the past 6.5 years, after previously working with Stephen Edwards Constructions, VSL and Arenco. With Fulton Hogan, he has predominately worked on road upgrades such as the Gerringong Upgrade and the King Georges Road Intersection Upgrade. His role on the M4 Smart Motorways Project has engineering looking after the design and construction of the temporary works, including the soil nail wall and anchored pile wall which temporarily support the M4 and the construction of the widening of Reservoir Road Retaining Wall and Bridge permanent works.
Emson Makita
WA Bridges and Civil Structures Team Lead

The proportion of timber bridges in Western Australia (WA) is approximately 45 percent of the state stock. The timber bridges are largely located in the South West, Great Southern and Wheatbelt Regions of WA.

This paper discusses a selected number of timber bridge replacement projects that have recently been undertaken in WA, on which the author was involved as a design leader.

Design considerations such as geotechnical, waterways requirements, future maintenance, environmental issues, durability, whole of life cost, construction staging, community requirements and expectations, and heritage are discussed. Whilst the paper provides an in-depth discussion on the design and replacement of Bridges 0024A and 0025A, which both carry the Albany Highway in Williams - Wheatbelt Region, the author also discusses the challenges met and solutions adopted for Bridges 0083A, 0661A, 0541A, 0904A, 3197A, 3210A and 4860A. Except for Bridge 0904A, which carries a road over rail in a significantly constrained built-up residential area in Perth, the rest of the bridges discussed are in Regional WA. The design solution for the superstructures largely entailed the use of precast prestressed concrete planks and Teeroffs. Simply supported and integral superstructure solutions are discussed as part of this paper.


Emson is Chartered Engineer with both the ICE in the UK and Engineers Australia. He has experience in the inspection and design of bridges of various forms of construction in the UK and Australia. He has led and delivered numerous bridge and civil structures projects for Main Roads WA, VicRoads, Public Transport Authority of Western Australia, Brookfield Rail, Network Rail, and the Highways Agency.
Dara McDonnell

A novel double-skin tubular arch (DSTA) bridge system is being developed at the University of Queensland as a collaborative effort of several organisations.

This new bridge system builds on the existing research on hybrid double-skin tubular members (DSTMs) which consist of an outer FRP tube, an inner steel tube and a layer of concrete sandwiched between them. DSTA bridges are light-weight, durable, of low-cost and rapid to construct, thus providing a highly attractive alternative to traditional bridge systems.

This paper presents the design and construction of a full-scale DSTA bridge prototype in the laboratory. The design procedure, based on existing design provisions for DSTCs, is briefly presented.

The construction process of the DSTA bridge, including the fabrication of steel and GFRP segments, assembly process, fabrication of joints and concrete casting, is described in detail and discussed. Two methods are discussed for the fabrication.


Dara is a senior bridge and civil structures engineer in Arup’s Sydney office. He has over 15 years of experience in the assessment of existing infrastructure structure assets on a wide range of transport and energy infrastructure.

Georgina Baxter
Senior Bridge Engineer
Srivelan Kathirgaman
Project Director


Aurecon was appointed by V/Line to undertake an investigation, assessment and design of 7 structures along the North East V/Line corridor. The scope included the survey, detailed bridge inspections, assessment & strengthening, deck replacement and replacement of bridges.

For the survey, Aurecon used Terrestrial Laser Scan Surveys to generate a high definition point cloud model of the bridge. This model was used in confirming various dimensions and essential details of the bridge without an engineer performing a detailed inspection of the 7 bridge sites. The information from this survey together with the available as built drawings and historical data was used in the load assessment of the bridges. The point cloud model was then used to generate a 3D model of the bridges in REVIT software. This facilitated the design and detailing of the strengthening works so that there will be a greater confidence that details will fit in well within the existing constraints. This is important as all these works are performed during a track occupation and a delay due to lack of fit may result in not being able to complete the works within the set time frame.

Deck replacement for this project included the use of V/Line’s standard steel decking system and detailing to fit within the constraints was a challenge. One of the bridges along the corridor was replaced and a complete prefabricated solution was developed for this bridge to enable a quick construction.

This paper will discuss the benefit of the use of point cloud survey and 3D models in developing solutions for rectification works, common defects found on these bridges and the various strengthening schemes that have been adopted to make the construction possible within a short time, detailing challenges of the V/line steel decking system and finally describe the fully prefabricated solution for the replacement bridge.


Georgina Baxter is a Senior Bridge Engineer, with Aurecon in Melbourne, with over 10 years’ experience in the design of bridges, foundations and other civil infrastructure. She brings specific experience in the design of road and rail bridges which has involved interdisciplinary design aspects with other civil areas including geotechnical, hydraulics and roads; and experience in the assessment and renewal of existing rail bridges and infrastructure.
Ken O'Neill
Bridges Leader NSW
Brian Killeen

Senior Bridge Engineer,

Jaime Granell
Technical Director Australia & New Zealand


The new railway crossing of the Pacific Highway at Warrell Creek on the NSW North Coast comprises an innovative “pergola” structural form to carry the railway loading over two spans. The single track North Coast Line was deviated during a track possession to allow for a bulk excavation and bottom-up construction of the structure. The substructure comprises reinforced concrete gravity retaining walls up to eight metres in height and supports a superstructure comprising prestressed concrete girders that vary in spacing for the high skew of 50 degrees.

The presentation will cover the design process including the alternative design options considered, the constructability considerations and the benefits of deviating the rail alignment temporarily to facilitate construction.


Ken leads Aurecon's bridges team in NSW comprising approximately thirty people and is a Technical Director within the Infrastructure Group in Sydney. He has nineteen years’ experience in the detailed design, documentation and construction of major highway and motorway upgrades in NSW and Victoria. Ken was the structural design leader on the Warrell Creek to Nambucca Heads project which comprised fifteen major bridges.
Marcia Prelog - 1

The bearing replacement design for the bridge crossing Nepean River at Blaxland’s Crossing, Wallacia, was initially presented at the 2017 Small Bridges Conference by Arcadis.

The five span prestressed concrete bridge comprises slender concrete blade piers within the Nepean river. A distinctive twist to the pier layout provides perpendicular support to the superstructure, whilst lessening the impedance of flood water by skewing the base of the pier parallel to water flow.

Aurecon prepared an alternative bearing support design which resulted in Wollondilly Council awarding the construction contract to Complex Civil contractors.

The new bearing supports feature innovative steel brackets braced to the sides of the pier with high strength stress bars. This design has been successfully adopted on other Aurecon bridge projects in the past.

Whilst this project is ultimately about the replacement of elastomeric bearings, this paper discusses the progression of this innovative design from concept stage at tender, the use of LIDAR technology through to detailed design, fabrication and construction.


Marcia Prelog is an Associate within Aurecon who has extensive experience a variety of bridge structures in Australia and overseas. Her 18 years in the Bridges discipline encompasses design in steel, concrete, composites and timber.
Marcia Prelog - 2

The James Street underbridge is a masonry arch bridge built in 1869, which is a Sydney Trains asset. The bridge is west of Lithgow Railway station and carries two tracks.

The bridge is of heritage significance as it is the second oldest stone arch railway bridge in NSW still in use and was designed by renowned engineer John Whitton. The bridge is a three-span sandstone arch structure and is a great example of sandstone arch construction of its era.

Aurecon undertook a load rating assessment with the aid of specialist arch analysis software Archie-M and with guidance from Australian and international standards and codes.

The findings of the initial condition assessment and load rating suggested possible settlement and lateral instability of the arches, necessitating arch crack repairs and lateral strengthening. The load assessment provided a decreased capacity to carry freight loads due to the existing defects.

To increase the arch capacity for current loading and further extend the service life of this historic structure, Aurecon undertook the design of replacement tie rods, arch lateral strengthening and crack repairs. The design was heavily coordinated with NSW heritage.

The behaviour of stone masonry arch structures, the effect of the tie rods’ contribution to the spandrel walls and the significance of defects such as arch cracking on the load rating and refurbishment design are some of the important features that are explored in this paper.


Marcia Prelog is an Associate within Aurecon who has extensive experience a variety of bridge structures in Australia and overseas. Her 18 years in the Bridges discipline encompasses design in steel, concrete, composites and timber.
Nathan Roberts
Senior Bridge Engineer

Buried Corrugated Metal Structures (BCMS) offered a fast, cost effective form of construction for road crossings and consequently over the years a number have been installed on the NSW road network. Roads and Maritime Services NSW currently have approximately 70 BCMS with spans in excess of 6m.

Roads and Maritime Services, Hunter Asset Management Division has recently undertaken a detailed assessment of all six BCMS in the region. The structures range in span from 3.2m to 11.5m and accommodate local road, fauna and pedestrian movements. The structures are all of multi-plate construction and are either arches or elliptical tunnels. Detailed inspections of the existing structures was undertaken including extensive ultrasonic thickness testing of the existing plates. This information was then used to advise PLAXIS soil structure modelling to assess stresses in the structures. Remedial options were then developed. 3D terrestrial laser scanning was also undertaken for each of the structures. The point cloud data from the scanning was used to assess structure geometry and serves as a baseline for ongoing monitoring of deformation and corrosion.

This paper will focus on the investigation findings. In addition, practicalities and benefits of 3D laser scanning will also be discussed.


Nathan, BE(Hons), MIEAust CPEng NPER, is a Senior Bridge Engineer at Aurecon with over 13 years experience in the design and construction of bridges and civil infrastructure. Nathan's design background is supplemented with construction experience as a temporary works coordinator on large rail infrastructure projects in the UK. Nathan was the project leader for the recent assessment of six BCMS in the Hunter Region.
Geoff Thompson
Senior Bridge Engineer

The New Zealand Transport Agency and Watercare Services Limited have jointly funded the design and construction of the Tirohanga Whanui Bridge.

This pedestrian and cycling bridge is being constructed on the North Shore of Auckland across SH1 as a gateway structure within the Northern Corridor Improvements Project. The multi-functional bridge also conveys a 508mm diameter water main across the motorway, building resilience to the water supply network. It is a great example of form meets function whilst expanding the architectural design through structural features. The 106m long truss bridge consists of three spans, with organic voids that vary in aperture by responding to the stresses in the structure.

This paper will cover the design development and construction of the bridge including concept design, layout, stakeholder engagement, structural detailing and analysis, erection methodology, and construction challenges.


Geoff Thompson has 10 years’ experience in bridge design, management and construction. He has worked across multiple geographies including South Africa, Dubai, Fiji and New Zealand. He is passionate about all things 'bridge' and within Aurecon's Auckland office, leads teams in the delivery of civil structural and bridge projects.
Oliver de Lautour

The New Zealand Transport Agency has a bridge replacement programme in the Northland region of New Zealand to replace existing single lane bridges on the State Highway network with two lane structures.

Taipa and Matakohe bridges are the first to be replaced in the programme and this paper presents the design and construction of these three structures. Taipa bridge consists of a 4-span structure constructed across the Oruru River the with precast hollowcore units and a length of 107m. Matakohe Bridges consist of two structures constructed with precast super-tee units over tidal estuaries. The bridges have span arrangements of 2 and 6 spans and lengths of 55m and 191m respectively. The bridges have spill through abutments and are supported on bored piles into component bedrock.

The paper will cover the design process including technical challenges of; seismic induced soil movements acting on the structures, tsunami loading and integral bridges. The paper will also cover incorporation of Iwi artwork into the bridge, Safety in Design process undertaken to address concerns with people jumping off the bridge into the River below at the Taipa site and construction of the bridges.


Dr Oliver de Lautour is an Associate at Aurecon, New Zealand with 14 years’ experience in structural design and is a Chartered Professional Engineer. He has a PhD in Civil Engineering studying Structural Health Monitoring. His background is predominantly in the detailed design of bridge structures in the Australasian and South Pacific regions. His experience includes undertaking complex bridge analysis and design, working collaboratively in multi-disciplinary design teams and bridge aesthetics. He has previously presented at the Small Bridges Conference.
Peter Masterson
Principal Bridges
Russel Odendaal
Bridge Engineer


The Little Doris Creek Bridge is a single 25m propped span consisting of TMR deck units with a composite deck. The bridge crosses Little Doris Creek which has an existing 8 cell box culvert structure to be removed during the staged construction works. The bridge is supported by closed ended steel driven tubes, which are later filled with reinforced concrete. Shotcrete facing spans between the piles and a rock filled berm was specified in front of the vertical abutment wall for additional robustness.

This paper describes the design journey and construction challenges in developing the final design solution which ranged from options to retain and strengthen the existing 8 cell box culvert structure to the final single span bridge solution being presented. The staged construction involved top down excavation and thus a temporary tie back system using tied sheet piles was required, to support a 5m deep vertical excavation facilitating the culverts removal and associated earthworks.

The design considerations and solutions are presented which include temporary staging/works, a non-standard piling system requiring TMR approval, sensitivity analysis of the rock filled berm support, flooding/rapid draw down effects, durability of steel driven piles and addressing client concerns.


Peter Masterson is the Principal Bridge Engineer for the BG&E Brisbane office and is the Design Lead for the structures on the Ipswich Motorway Rocklea to Darra project. Peter has over 24 years design experience on steel and concrete bridges of various forms and complexity and has been the structures team lead on numerous large projects throughout QLD including the Northern Busway, Ipswich Motorway D2G, Ipswich Motorway R2D and Smithfield Bypass in Cairns.

Russel Odendaal is a Bridge Engineer for the BG&E Brisbane office. Russel has over 7 years’ experience in the analysis, design and construction of various structures from integral prestressed concrete bridges and viaducts to braced excavations. Russel has worked on large scale projects in Australia the UK, Asia and the Middle East.
Thomas Wazny
Ocean Engineer
BridgePro Engineering
Nam Do
Project Engineer
BridgePro Engineering


As part of the long-term North Bank Development, City of Launceston proposed a pedestrian bridge to provide a connection between Seaport and future Riverbend playground.

The 120m long and 4m wide truss bridge was engineered and installed by a local firm – BridgePro Engineering in Latrobe, Tasmania. The bridge was constructed with 11 main prefabricated steel components; featuring 3 off 35m spans with 10m long by 8m wide landings at the two central piers. The superstructure is approximately 90T of steel with a recycled plastic deck and stainless-steel side panelling. The bridge is supported by a quad -pod-pier which 4 No. piles continuing from the founding level to the underside of the landing and braced together at river bed level by a concrete mass.

This paper will discuss the design (challenges and solutions) and construction of this bridge. One of challenges of building the bridge is the complicated hydraulic (flood) model where the water flows in both directions. The landing platform and quad-pod pier system also stiffens the structure therefore reducing vibration and providing a comfortable vibration frequency for pedestrians.

The bridge was successfully installed and opened to the public on 1st August 2018. The bridge soon becomes the great asset for the community around the area.


Thomas Wazny has a dual diploma in civil and mechanical engineering and graduated with a bachelor’s degree from the Australian Maritime College in 2014. Since joining BridgePro in early 2015, he has been involved in the design and installation methods for more than 50 bridges and marine projects.

Nam Do is SMP Project Engineer, responsible for providing technical engineering support throughout all stages of a project. He has been working around Australia from Energy, Mining and Utilities to various construction projects. With practical experience from different industries, Nam is able to find innovative solutions to ensure a smoother and better projects delivery. 
Michael Kruettgen
Senior Bridge Engineer
Mike Kirumba
Senior Bridge Engineer


The Nan-Tien Pedestrian Bridge project involved the design, construction and commissioning of a new pedestrian footbridge over Princes Highway to link the Nan-Tien Buddhist Temple on the South side of the motorway with the recently built Nan-Tien Institute on the North side of the freeway.

One of the main guidelines for the overall Nan-Tien Institute development plan was to support and inspire learning and the pursuit of research and creative practice within a Buddhist framework. In this context the pedestrian bridge is the entry statement and the first architectural feature and therefore the aesthetics of the bridge and the incorporation of landscaping areas and a flowing safety screen was important.

The large centre span of the 112m long bridge required the preferred Super-T girders to be made continuous and integral with the piers. This caused various challenges for the design and construction of the bridge, the temporary works and the approval process.

The main challenges and lessons learned will be covered in this presentation.


Michael Kruettgen is a chartered Senior Bridge Engineer with Cardno in Sydney with over 13 years' experience covering concept and detailed design of bridges and civil structures in a variety of countries including Germany and Australia. His design background is supplemented with construction experience as a Site / Project Engineer for Bridges on large rail infrastructure projects in Australia. Michael was the Lead Designer for the Nan-Tien pedestrian bridge.
Ray Crampton
Operations Director
Commercial Marine Group

Bridge scour is the removal of seabed or riverbed sand from around bridge and wharf abutments and piers. Scour is caused by fast moving water, thus compromising the integrity of a structure.

Commercial Marine Group has designed and installed custom scour mattresses for a range of Clients and will discuss the challenges presented by the Client and the solutions provided.

Recent projects that will be presented to delegates is the installation of the Callaghan Park Boat Ramp, Rockhampton, 80CBM of concrete in-situ installed into custom designed grout bags and the Kingsford Smith Drive Project in Brisbane, where the team assisted with the installation of 330 scour matts, weighing between 30 and 80 tonne each.

Secondly you will be presented with the sewerage outflow solution on the Kingsford Smith Drive Upgrade Project, Brisbane.

Both projects presented unique challenges and learn how and why the final solutions were developed and installed in a subsea environment using commercial divers and specialized floating plant.


Ray Crampton is founder and Director of Commercial Marine Group (CMG), a marine construction company specialising in the provision of commercial diving services and other subsea solutions. Ray has extensive experience in construction diving and project managing marine construction projects, with qualifications in Hyperbaric Operations Project Management and Business Management. Ray has 19 years occupational diving experience, including 10 years with the Royal Australian Navy.
David De Saedeleer
Joseph Marra
Department Manager,
Global Design Technology, BELGIUM
Project Engineer
Global Design Technology, BELGIUM


Tested crash barriers (also called parapets) on bridges are usually made to retain heavy vehicles and to be used as widely as possible with an existing budget. These barriers usually show several disadvantages for use on rural bridges including:
  • High loads transmitted to the bridge decks 
  • Maintenance relatively difficult due to installation and dismantling time
  • Pedestrian protection rarely considered
  • Low level of aesthetic
In Belgium to address these limitations, and due to the increasing needs from Local Road Authorities to have solutions for such bridges, a specific product was developed to meet these requirements.

The new bridge parapets were required to cover the different containment levels usually required on secondary roads in Europe depending on the traffic level. Three versions of the parapet have been developed and tested for the N2, H2 and H4b containment levels. Respectively aiming to stop a 1500kg car, a 13 tons coach and a 38 tons truck. The energy levels of these classes are above the energy classes of TL2, TL4 and TL6 level according to MASH.

Systems have been developed for the specific constraints of rural bridges using Finite Element Simulations and advanced LSDYNA models. The systems were then crash-tested to assure their effectiveness in case of impact.

Traditionally rural bridges were not designed to support the increased load that higher containment devices generally require and so often need expansive civil engineering works when the road safety devices are upgraded. The technical paradox to resolve by developing the new system was to be able to contain different type of vehicles but, at the same time, transmit the least forces to the bridge decks and achieve a low impact severity value. Tested according to EN1317, the systems should satisfy the corresponding MASH containment levels.

The paper will show through case studies, that the low forces transmitted compared to existing systems (more than 50% less), allow the systems to be placed on existing bridges without the need to reinforce them despite not having been designed for crash tested parapets. The systems have been designed with ease of installation and dismantling and to be slim to permit placement on the edges of narrow bridges typical of common rural bridges.

This paper will discuss:
  • Innovations in Design, Construction and Maintenance 
  • Investigation and Testing 
  •  Asset Management 
  • Repair, Maintenance, Refurbishment and/or Strengthening 
  • Use on Timber, Concrete, Steel and Composite Bridges as well as Culverts 


David De Saedeleer is an engineer, CEO of Desami (founded in 2012), with over 15 years’ experience in the road safety devices. He is a member of the standardization committee for EN 1317 and of Consultative Council COPRO which defines the rules of aggregation of road restraint systems in Belgium. Clément Everaert is a development engineer working for the company Desami.

Joseph Marra is an engineer managing the “crash and dynamic” department, with over 15years’ experience in the road safety equipment calculation and normalization. He is a member of the standardization committee for EN 1317 and he participates to the TRB committee in charge of US regulations (NCHRP350 -> MASH).

Alexandre Dewaulle is a calculation engineer in the Crash and Dynamic Department.
Royce Toohey
Support Services Engineer
Eurobodalla Shire Council

Eurobodalla has been undertaking a program of bridge renewal and replacements to reduce deficiencies and to better manage its transport network.

Due to significant government funding, a low-level rural timber bridge that was of poor condition and utilised by a high percentage of commercial vehicles, was replaced by a 85m concrete structure at a higher level. This work was done under a Design & Construct Contract.

Simultaneously, a 130m long timber bridge in another rural location was replaced like-for-like by Council’s internal staff, using a combination of Council and grant funding.

Both bridges are single-lane bridges located in remote areas of significant environmental benefit with imposed restrictions on the impacts allowed on their respective marine environment.

This paper will discuss the desired outcomes from each project and compare the techniques used, a cost comparison of the two projects, and issues encountered.


With over 40 years’ in local government, Royce has had significant experience across the range of local government responsibilities. Currently responsible for the Bridges and Marine Structures of Eurobodalla Council as well as other facets of Service Delivery, he was previously their Asset Engineer providing him with experience from project development through construction to long-term management. He holds a degree in Civil Engineering from USQ as well as a Masters from UTS in Engineering Management.
Behzad Golfa
Structural Engineer- Bridges

This paper presents the utilised method to reduce the depth to span ratio of Ashton Avenue Bridge. The bridge is a single span with an overall length of 20m and overpasses the Perth Fremantle Railway in Claremont WA.

Due to the restriction of vertical clearance, a superstructure with a maximum deck thickness of 520mm was allowed to be used. To achieve this and to reduce the superstructure thickness, the battle deck plank with integral abutments was used as the preferred option.

This paper will firstly, recall the bridge specifications and the other constraints that characterised the design of the battle deck planks and the integral abutments. In the second part, the design criteria followed in designing the battle deck, abutment and foundation are presented.

The structural analyses were set out in accordance with the construction sequences using Spacegass and Aces software.

The design results indicate that using the battle deck plank superstructure on a bridge with integral abutments may reduce the depth to span ratio considerably. Details of completions and finishing works are finally given.


Behzad Golfa has over 14 years of experience in the investigation, design, construction and management of Australian and international infrastructure projects, involving work with major Iran and Australian consultants and contractors. Behzad’s experience covers a wide variety of projects including road and rail bridges, offshore and oil and gas projects and infrastructure development. This has involved planning and delivery of projects at all stages from initial feasibility
Graeme Joynson
Technical Director - Bridges

The Pacific Highway north of Gosford is the urban arterial road providing access to Gosford’s northern suburbs and the Pacific Highway (M1) at Ourimbah.

This project represents Stage 3B of the NSW State Infrastructure Strategy, which consists of upgrading approximately 1.6 km of the Pacific Highway to a four-lane urban arterial road between Ourimbah Street and Parsons Road, Lisarow, and includes the replacement of the existing steel bridge over the Main Northern Railway Line at Railway Crescent on the Pacific Highway.

The new bridge is a complex structure of two simply supported spans of prestress Tee-bulb girders with an in-situ concrete deck.

The skew and bridge width varies considerably between the two spans, due to a tight horizontal curve in the road design line within the second span. The first span is a conventional arrangement with a 45 degree skew, and the second span, which is significantly wider, forms an 80 metre long skewed tunnel over the railway.

This paper focuses on the design of the new concrete structure to fit within numerous constraints presented by bridge construction on a busy highway over a major railway.


Graeme Joynson is a Bridge Design Engineer who has a career spanning 4 decades encompassing experience in both structural design, and construction of bridge, marine and road projects. This includes detailed structural design and documentation of all forms of bridges, both as a team leader, and the primary designer.
Hai Le
Senior Bridge Engineer
Nicholas Eduljee 
Structural Team Leader


The purpose of the program is to demonstrate a new structural analysis tool for undertaking structural analysis for bridges at network level.

There is a large number heavy vehicles that across existing bridges; the mass of these vehicles are normally significantly heavier than the original design loads, therefore, the existing bridges need to be assessed with efficient methodology to determine whether they can support the heavy vehicles or not. With the introduction of the NHVL and formation of the NHVR the ability to provide accurate responses to permit applications and to give as much access to these larger and heavier vehicles whilst maintain a reasonable level of safety falls to the road managers. The programme we are presenting provides asset managers with greater understanding of their network and the ability to accept the proposed vehicles across their bridge confidently. If used across the complete network can also provide insight into the maintenance and replacement programme allowing road managers to use the valuable resources they have efficiently.

The new structural computer program has been developed successfully replicating the use of line load analysis. The program can analyse and determine design actions including bending moments, shear forces and support reactions for all bridge arrangements such as single or multi-span simply supported spans, continuous spans, balanced cantilevers and internal hinged joint structures.

The new structural analysis program will help bridge owners undertake a screening of their bridge assets providing a Live Load Factor quickly and effectively within a short time frame. The software is able to analyse a hundred bridges within a couple of seconds. The program is still undergoing further development with the intent to undertake a higher level of assessment. This extension will be able to undertake structural analysis and calculate bridge capacities using 3-D grillage model and 3-D frame at network level with the relevant inputs being provided.


Hai Le is a Senior Bridge Engineer at GHD in Hobart office. He holds 2 Bachelor degrees (Software Engineering, Civil Engineering). In addition, Hai also holds a Master Degree in Construction Engineering. Hai has a wide range work experience from construction engineering to consultancy. Currently, he is focusing on detailed design, assessment and strengthening for differing bridge type such as the pre-stressed, post-tensioned concrete structures and composite structures. He is fascinated in writing computer programs for bridge structural analysis and design
Muhammad Shariq
Senior Structural Engineer Bridges
Palisa Huoth,
Structural Engineer Bridges – South Queensland


To support the growing population and subsequent demand on road infrastructure, ongoing upgrade of Queensland’s transport network is being undertaken. These upgrade works require design consideration to maintain the existing level of service during construction, as well as maximize the retention of the existing assets in order to provide the most viable solution. In terms of bridge assets, this requires the consideration of widening the existing deck on many of the current bridges.

Though provision for future widening has been made on a number of bridges throughout Queensland, it may not always adhere to the future performance criteria set for the widened structure. Thus, widening of existing bridges presents a multitude of challenges during each phase, from planning and scheduling to design and construction. In particular, the design of various structural elements to minimise impact on the existing structure and achieve construction constraints, the use of existing bridge elements and ensuring the required durability is achieved.

This paper addresses widening of existing bridges on the Logan Enhancement Project undertaken by CPB Contractors and GHD/SMEC led design JV completed for client, Transurban Queensland. The paper aims to provide an insight on some of the key challenges encountered during different stages of the design and construction that can be utilised as an opportunity to improve the approach on future upgrade works.


Shariq is a Senior Bridge Engineer working within the Bridges, Marine and Materials Technology Team of GHD. He has more than 12 years of experience in bridge design and worked on a variety of bridge projects in the Middle-east Asia and Australia. He worked on Logan enhancement project as senior design engineer on Zone 3 bridges’ widening package. :

Palisa is structural engineer working within the Bridge, Marine and Materials Technology Team of GHD. Palisa has had 5 years of broad range experience in structural engineering with a focus on bridge design. Palisa has experience in all stages of bridgeengineeringprojects, from preliminary design through to detailed design and construction. Palisa was involved in the detailed design and construction phase services on the Logan Enhancement Project.
Rod Tebbutt
Manager – Special Projects
Gympie Regional Council
Chris Dowding
Director / Senior Structural Engineer
Tod Consulting


The Mary Valley Branch Railway was opened circa 1914, to connect the rich agricultural lands of Mary Valley to the goldrush country that became the town of Gympie. In more recent times (1998-2012), the railway carried a tourist steam locomotive service, known as the Mary Valley Rattler or Gympie Rattler. The railway line was closed in 2012 due to insufficient funding available to maintain the aging infrastructure.

In February 2017, the Queensland Government pledged a grant to help resurrect the Rattler service. There were many challenges: all of the track needed to be re-sleepered and realigned, all fifteen rail-over-road bridges needed major restoration works, and the locomotive had to be fully rebuilt.

This paper focuses on three (3) riveted steel bridges at the northern end of the railway which were constructed during the 1890’s, as part of the North Coast Railway. It describes the investigation and assessment of options available to the asset owners, and the subsequent repair methodologies; all these activities were carried out under a lean budget. This work included repairs and replacement of steel components which came from an era before welding had been invented. Historical steel records indicated that welding of this material could result in brittle failure, so the repair methods were tailored accordingly.


Rod Tebbutt has 35 years’ experience, 30 years with the Department of Transport and Main Roads (TMR) and the past 5 years with Gympie Regional Council (GRC), Positions have included Construction Technician, Civil Designer and Project Manager in South East Queensland. His final position with TMR was that of Principal Project Manager responsible for management of the planning, design and construction of the Bruce Highway Upgrade – Cooroy to Curra. Within GRC, his role has been in the project development and contract management of many of their significant projects the highlights of which include the Gympie Aquatic Recreation Centre and the restoration of track and structures for the Mary Valley Heritage Railway

Chris Dowding designs, maintains and modifies Bridges, Infrastructure and Placemaking Structures. He also works with Local Government asset managers, who have the challenge of managing ageing infrastructure & facilities. He gives them clear action plans to minimise whole-of-life costs and keep the community safe. His practical approach has solved challenging issues during construction and maintenance of numerous projects. Examples of his work include Albert St bus tunnel and Roma St bus platforms 1 & 2 (Brisbane's Inner Northern Busway); Munna Point Bridge Remediation (Noosa); Pickering Bridge crossing the Mary River (Moy Pocket); and the restoration of bridge structures for the Mary Valley Heritage Railway.
Ashraf Gamal Nayel
Researcher - Structural Engineer
Housing and Building National Research Center (HBRC), EGYPT

Since 2013 and until now (2018), Egypt is rapidly building many new roads and other infrastructure projects. A huge number of small and medium span bridges have been constructed and many others are still under construction.

The main and common challenge in all projects (especially national projects) is the tight time allowed by the government to finish the works. Hence, precast reinforced and post-tensioned concrete beams in addition to steel girders are widely used for decks. However, Obstacles are encountered in some cases which in turn enforce the designer to choose another structural system such as concrete box girders, and what is called slab-on-piles (SOP) system.

This paper will present the different structural systems that are used now in these projects all around Egypt. Advantages and disadvantages of each system will be is discussed with examples of typical  projects and dimensions used.


Ashraf Nayel has a Master of Science in Structural Engineering, and has 6+ years of practical experience in the design repair and strengthening of different kinds of buildings, bridges and other civil structures in Egypt and the Gulf countries. He also a technical assistant for several committees of the Egyptian standards (codes) of practice such as Prestressed Concrete committee and Pultruded FRP Sections Committee.
Dean Ferguson,
General Manager
Infracorr Consulting
Ian Godson
Director and Principal Engineer
Infracorr Consulting


Major rehabilitation projects for severely deteriorated reinforced concrete structures can easily run into the millions of dollars, and therefore maintaining a suite of operational infrastructure becomes increasingly difficult when contending with limited budgets. Unfortunately, the deterioration of reinforced concrete is not visibly evident until very late in the deterioration cycle, and by then significant works are typically required.

The authors  will present four case studies which explore the ability of modern investigation techniques to diagnose the current condition and expected life of a bridge.

In each case, a different remedial strategy was selected, always aimed at either preventing/delaying future deterioration or at treating the active deterioration. The case studies consider bridges ranging from 20-100 years old, constructed using various methods, exposed to different environmental conditions (non-saline river to full marine) and subject to different load requirements (pedestrian to highway traffic).

The projects illustrate the benefits of early investigation of the concrete structures which enable the prediction of the cause and onset timeframe for future deterioration. Once this information is available, the selection and implementation of suitable preventative maintenance works (such as coatings) can significantly delay more costly repairs. However, even in the cases where corrosion has initiated, mid-stage intervention using targeted corrosion control techniques show the ability to provide long term life without the cost and disruption of a full scale rehabilitation.

A brief overview of available preventative maintenance and rehabilitation techniques, when to use them and their relative cost is also presented.


Dean Ferguson still spends as much time as possible getting his hands dirty in sewers or under bridges! He has a decade of experience undertaking condition assessments of structures, includes detailed destructive and non-destructive testing of various construction materials such as concrete, stainless steel, FRP and protective coatings. Dean is the current President of the ACA Victorian Branch, where he has been a branch committee member since 2010.

Ian Godson has 35 years experience in all aspects of remedial engineering including condition assessment, remedial design and cathodic protection design and installation. Ian’s experience with cathodic protection of reinforced concrete structures traces back to 1987 when following training in Italy he introduced the technology to Australia. A regular presenter at technical conferences around the world, Ian’s commitment to being at the forefront of remediation technology is a strong driver in his ongoing success.
Hamidreza Sadeghi
Senior Geotechnical Engineer
Katahira Engineers International, JAPAN
Romualdo Canlas
Group Manager


This paper presents the summary of pile test program for The Metro Manila Rail Transit System 7 (MRT-7). The 22.8 km project has its alignment over the challenging geology of manila in vicinity of major seismic sources. Therefore, the foundation design and quality assurance of the viaducts and foundations were of utmost importance.

The pile test program for MRT-7 project consisted of testing methods employed for evaluations of structural integrity and load bearing capacity of deep foundations among which Bi-Directional Load Test (O-Cell) had never been done in The Philippines before. The O-Cell test had to be preferred over conventional static load test method due to technical, quality and safety requirements.

This paper discusses the pile testing program in general and O-Cell test in particular along with the test results and specific findings


Hamidreza Sadeghi has more than 11 years of consultancy services experience asa geotechnical engineer on various infrastructure study and design. Having studied his masters’ in geotechnical engineering in Tehran, Iran he did his Ph.D. in Kyoto University in 2014 and works for Japanese consultant companies since then.
Giuseppe De Filippo
Principal Bridge Engineer
Carla Rossimel
Structural Engineer


Over eight years, the Victorian state government has committed to removing fifty of its most dangerous and congested level crossings across Melbourne.

Two of these level crossing removal projects; Buckley Street, Essendon and Camp Road, Campbellfield; were positioned on key arterial roads in highly constrained residential areas of Melbourne. Removed as part of the North Western Program Alliance, it was imperative that the two new bridges (a rail underbridge and a rail overbridge) were designed to have the least disruption on the community and environment, ensuring that Melbourne was able to keep moving during the works.

This paper discusses the engineering solutions developed and the design strategies used to minimise schedules and perform the majority of construction works whilst trains were running and roads were open. Whilst both structures are integral bridges with decks cast on ground and supported on CFA piles, each structure presented its own site-specific challenges. Notwithstanding this, challenges were overcome, and the amount of time rail or road operations were completely suspended were limited to five and fifteen days, respectively. To date, the Camp Road project is the fastest level crossing removal within the program of works.


Giuseppe De Filippo is a skilled structural engineer with more than ten years of experience in a large array of construction projects. These range from railway and road bridges to power stations, to tunnelling and buildings, in Australia and Europe.

Carla Rossimel is a structural engineer with four years of experience in project management and structural engineering within the mining, oil and gas, maritime and bridge sectors. Through her time at KBR, Carla has worked on a number of transport projects, designing a number of road, rail and pedestrian bridges.
Jeevan Senthilvasan
Chief Discipline Engineer Structures

The Gateway Upgrade North (GUN) Project is a major upgrade of an 11.3 kilometre section of the Gateway Motorway between Nudgee and Bracken Ridge, in Brisbane. The scope of the project early works included structural assessment of the existing culverts and extension of the culverts in the widening section of the motorway. Many of the culverts were located in soft compressible soils which were subject to significant settlement. The upgrade works caused increased loading on the existing culverts from additional fill and an increase in design loading from NAASRA-1976 to AS5100-2004 which resulted in predicted differential settlement between the existing culverts and the culvert extensions.

For the existing culverts, while the increased fill above the culverts results in additional loading, it allows the wheel loads to distribute to a larger footprint resulting in reduction of load intensity. A methodology was developed to assess the interaction between the fill depth and the total load applied to the culvert, based on the load effects from the soil and wheel live loads.

Differential settlement between existing culverts and the culvert extension causes a vertical step at the interface unless a shear connection is made at the interface between the culverts. Any vertical misalignment between the culverts can cause hydraulic turbulence which restricts the flow, cause erosion in the long run and generate reflective cracking in the road pavement. However, rigidly connecting the existing culverts to new culverts will cause very high stresses in the reinforced concrete section at the interface when soil under the culvert extension settles.

This paper discusses design considerations for culvert extension in soft soil, high settlement locations and in particular, special connections that are considered to avoid large stresses at the culvert extension interface while maintaining an uninterrupted hydraulic flow in the culvert.


Dr Jeevan Senthilvasan is a Chief Discipline Engineer and Industry Lead for Bridges and Structures in KBR Brisbane office. He is also the Technical Leader for the Civil Structures group, mentors structural engineers and monitors the standard of the design and documentation. He has more than 25 years experience in design of civil structures and is responsible for providing skills development, providing technical support to design team and promoting innovation and value engineering in major projects.
Sunthara Trang
Senior Structural Engineer

Queensland Rail undertook a project to replace three existing ageing timber rail bridges West of Laidley, Queensland. The purpose of the project was to improve reliability, operational safety and efficiency of services on the rail corridor. In late 2014, Queensland Rail awarded a contract to JF Hull Holdings Pty Ltd (JFH) for the design and construction of new structures to replace the existing timber bridges. Kellogg Brown & Root (KBR) was engaged by JFH for the design component.

A key challenge in the project was to demolish the three existing timber bridges, install the new structures and restore the services in 48-hour full track closures at two separate locations. The short timeframe track closures were planned by Queensland Rail to minimise disruption to freight and passenger train services. KBR and JFH examined risks associated with the project requirements and proposed an effective solution to replace the existing timber bridges with precast box culverts supported on precast base slabs which were joined together by cast in-situ stitches. The proposed precast structures enabled the construction team to install them in place within the short allocated timeframe. KBR design team carried out detailed design of precast base slabs with cast in-situ stitches, precast wing walls, cast in-situ apron slabs and cast in-situ kerbs. Construction staging was also undertaken in the design to allow installation of precast boxes, backfilling and track works prior to casting in-situ stitches to form complete base slabs. The precast box culverts were designed by the third party. Two large box culverts were designed to replace the three existing timber bridges.

The new structures were required to be designed to support dual ballasted tracks with Queensland Rail QR-300A railway loading at each bridge location. Existing rail levels were to be maintained while flood efficiency of the new structures was improved after the construction. The main works to be carried out in the construction were demolition of the existing timber bridges, removal of unsuitable materials, subgrade improvement, installation of new structures, earth works and embankment formation at approaches, track works and restoration of the existing services.

With thorough planning and design, the construction team managed to successfully complete the bridge replacement works in September 2015.


Sunthara obtained his bachelor’s degree in civil engineering in 1993 at the Kharkov Institute of Municipal Engineers in Ukraine. In 2000, he pursued a postgraduate study at the University of New South Wales in Sydney and obtained his master’s degree in structural engineering. Sunthara has been working as a structural engineer in Cambodia and Australia. His main duties involve structural design of bridges and civil structures.
Peter Newhouse
Asset Manager Structures - South West Region
Main Roads Western Australia

Main Roads WA, as the lead State road authority, has a responsibility under State Emergency Management arrangements for the restoration of the Main Roads network, including the clean-up and reconstruction of bridge assets during recovery operations. It was identified that there were limited emergency bridging options in the State that would be readily available in the event that a bridge was damaged or lost during an incident.

In 2012, Main Roads WA established a team comprising asset managers from all regions to develop an emergency bridging strategy.

The Emergency Bridging Team’s strategy included a recommendation to refurbish the Bailey bridge system owned by Main Roads and supplement this with a larger span system. The Team also recommended that Main Roads’ staff should be trained in the use of these systems.

This paper covers:
• the emergency bridging options considered by the Emergency Bridging Team
• the process of condition assessment and refurbishment of the Bailey bridge system
• the acquisition and utilisation of a n emergency bridging system
• emergency bridge storage arrangements and training of staff.


Peter Newhouse MIEAust CPEng has worked in Main Roads WA since 2001.At Main Roads Peter has been responsible for managing bridges on the State and National road network in the South West Region of WA. He has also worked closely with other bridge owners in the Region such as local government, by providing technical advice and programming bridge repairs and refurbishment on their behalf. Peter was involved in the re-establishment of a Bridge Maintenance Team that continues to provide specialist preventative maintenance services for timber bridges in the State. Recently, he has led a team in developing and implementing an emergency bridging strategy for Main Roads WA.
Dr Liam Holloway
Managing Director
MEnD Consulting
Nimal Jayasekera
Delivery Manger Structures
Main Roads Western Australia Main Roads Western Australia


Western Australia has hundreds of reinforced concrete bridges in regional areas that are exposed to relatively aggressive conditions. It is well known that chloride induced corrosion of the reinforcement presents a risk to the structural integrity of bridges. This is especially the case for bridge piers, which can be exposed to saline waters with tidal or seasonal variations; accelerating chloride ingress and in turn the rate of deterioration.

This paper presents a recent case study where a hybrid cathodic protection system was installed to manage the risk of corrosion to the cylindrical reinforced concrete columns on two adjacent bridges. The bridges cross the estuarine Serpentine River South of Perth, Western Australia and were of similar construction. One of the bridges was constructed in the early 1980s while the duplication was constructed in the early 1990s.

The paper will discuss the basic principles of cathodic protection for reinforced concrete; and how galvanic and hybrid systems offer a method to manage the risk corrosion for remote regional structures, where impressed current systems may be less practicable. The paper will also share some of the practical implications with installing Hybrid systems learnt from the project and how recent technology developments can help overcome these.


Liam Holloway’s unique skills and expertise as a materials engineer specialising in durability and corrosion, traverse key infrastructure sectors including marine, mining, defence and energy. Liam completed his PhD in the field of corrosion inhibition and monitoring for reinforced concrete structures at Monash University. Following this he has worked in both the consulting and contracting fields with a focus on asset condition assessment, remediation and maintenance. Liam has been involved with the design, installation, and monitoring of numerous reinforced concrete cathodic protection systems for bridges structures across Australia.

Nimal Jayasekera has 33 years of career history as a Civil Engineer with wide range of Design, Construction and Project Management experience in road and bridge projects. After completion of his Master’s Degree in University of New South Wales, he started working for Main Roads Western Australia. He has been working in Structures area for last 21 years delivering major bridge projects in Main Roads WA South West Region and is the Delivery Manager Structures for this region.
David Coe
Senior Principal

The revision to AS5100 in 2017 resulted in significant changes to the design loading and impact heights for all bridge barrier performance levels. These changes have increased the requirements for bridge barriers which are then reflected into increased cost of bridge construction.

The paper will explore the impact of the changes to bridge barrier design and, importantly, the impact on bridge construction costs.


David is a senior principal with over 35 years’ experience in the design and construction of civil/structural engineering projects working most of which have been associated with the design, rehabilitation and management of bridges. He has considerable experience working within a large project team acting as the pivotal point between designers, contractors and the client
Chris Morton
Principal Bridge Engineer

The Arden Street Bridge over the Moonee Ponds Creek is a seven-span cast-in-place reinforced concrete bridge constructed in 1923. Originally designed for a 16 ton roller, the bridge was strengthened in 2004 to accommodate vehicles operating at Higher Mass Limits.

SP AusNet requested approval from the City of Melbourne to use the bridge during the transport of various Heavy Load Platform (HLP) configurations, including 12 and 14 axle platforms carrying 130 tonne 150MVa or 162.5 tonne 225MVA transformers, as part of the West Melbourne Terminal Station upgrade.

Following a desktop load assessment, performance load testing of the bridge was undertaken involving the use of two semi-trailers. The mass of the test vehicles was progressively increased to 54.5 tonnes each. Sensors used during the testing included strain gauges, linear potentiometers and slip measuring load cells.

After the results of the performance load testing were evaluated additional testing was carried out on one representative beam. During this second stage of testing the bending and shear actions induced in the test beam approached the predicted Ultimate Limit State load effects for the proposed HLP loading.

This paper will describe the load testing carried out including the project constraints, identified risks and lessons learned.


Chris Morton has 15 years’ experience covering a broad range of bridge engineering activities including inspections, load rating, rehabilitation and strengthening design, concept and detailed design, feasibility studies, writing reports and specifications, cost estimates and hold point inspections.
Dr Andrew Sonnenberg
National Bridge Engineering Manager

Road and Rail managers own a variety of bridge assets which are aging and will need replacement. There is a risk that insufficient funding is allocated for these replacements and that the timing of funding does not match demand. When an asset fails to meet the required level of service it costs the community and this cost needs to be weighed up against the capital replacement cost to determine the cost benefit of capital replacement.

A methodology for prioritising capital replacements has been developed that helps simplify the complex process of considering all the level of service factors. The method utilises level of service information such as condition, load capacity, flood immunity, barrier safety and other factors to determine the cost benefit of replacements. The cost benefit ratios then determine the priority order for replacements.

This paper will discuss these issues and provide guidance on the methodology.


Andrew Sonnenberg has over 20 years' experience in the design of road and bridge projects in Australia. His work in both the public and private sectors has provided a sound understanding of the complexities of asset management and the skills to successfully project manage multidisciplinary projects through to completion. As national Bridge Engineering Manager at pitt&sherry, Andrew oversees the company's bridge network across Australia, and has a deep understanding of the country's best practices when it comes to bridge design assessment and management. His practical experience is reinforced by a strong theoretical background, which includes a Master of Business Administration and a PhD obtained from the study of the shear strength assessment of reinforced bridge beams.
Dr Mehdi Kalantari
Resensys, USA
Dr Pedram Mojarrad
Managing Director
Dez Pacific


This paper covers a new approach to scour critical bridge monitoring. Networks of connected devices were used to monitor scour critical bridges.

A system of connected wireless sensors were used to monitor the tilt (orientation) of bridge piers with sub arc second accuracy. In addition, a wireless ultrasonic water level sensor was used to monitor water elevation beneath the bridge. Also, wireless solar-powered cameras were used to provide constant visual feedback from the general bridge condition. To produce a model-based approach, temperature was monitored at the location of all sensors. For precision  of detection, analysis was conducted to produce a baseline model that predicts small deflections in bridge piers caused by temperature variations.

The models show that in most bridges, a typical quasi-cyclic pier deflection of around 0.005 to 0.05 degrees happens, where such deflection is resulted by daily temperature changes. Once the baseline models are developed and fully verified using a few weeks of data, deviation from the models is used for detection of bridge scour. The deviation often happens in the form of a new pattern of deflection caused by temperature, or in form of excessive non-returned tilting of bridge piers, implying settling or other forms hydraulic damage. Moreover, data from the wireless camera was used to further monitor changes in pattern of rocks/sediment around bridge piers.

The summary of findings in scour critical bridge monitoring presented in this project and presentation are:
  • The connected devices help achieve real-time condition awareness on scour critical bridges. 
  • Automated detection methods and alert generation


Dr Mehdi Kalantari has more than 22 years of experience in industrial instrumentation, communication systems, and wireless networks. Currently, he serves as the President and CTO of Resensys LLC, which he founded Resensys in 2008, with the mission of protecting infrastructure systems against aging, malfunction, and structural failure. Mehdi received his PhD in Electrical and Computer Engineering from the University of Maryland in 2005.

Pedram Mojarrad received his PhD in Civil Engineering from University if Technology Sydney in 2012. He is now founder and Director at Dez Pacific. Pedram’s field of expertise is health monitoring of structures, concrete materials and repair. Pedram has 16 years of experience in the industry.
Binh Pham
Technical Principal - Structures

Due to aging infrastructure and high demand to move heavier vehicles, there has been an increasing number of highway bridges that are required to be strengthened in Victoria. Finding a suitable bridge strengthening solution is not a straightforward exercise for most cases. The selection of a solution depends on many factors including contractor’s preferences, bridge types, bridge conditions, existing reinforcements, deficiency types and levels, traffic restrictions, site condition.

This paper presents a summary of traditional bridge strengthening approaches as well as more recent innovative approaches. The paper is based on the work by the author over many years assessing and strengthening Victorian bridges. The focus of the paper is on the theoretical effectiveness of these approaches for typical highway bridges in Victoria. To illustrate, a number of examples are shown including a bridge with composite prestressed girders and a bridge with composite haunched steel girders. These bridges are studied in details to show the pros and cons for each method of strengthening. These examples are analysed and designed in accordance with the new AS5100-2017.

The paper will provide a guidance to designers as well as bridge owners for selection of bridge strengthening solutions.


Binh Pham has over 18 year experience in structural design for various projects in Australia, Middle East and Southeast Asia. He has worked on numerous projects from large multidiscipline construction projects to smaller bridge assessment and strengthening projects.

Binh is a specialist in strengthening structures using fibre reinforced polymers and advanced modelling of bridges. He has authored/co-authored over 25 publications. He is the reviewer for Elsevier’s journals and ICE Bridge Engineering Proceedings.
Chris Bridges
Technical Principal - Geotechnics
SMEC Australia

Currently two Australian Standards can be used for the design of earth-retaining structures, AS5100.3-2017 and AS4678-2002. Although both claim to be limit state design methods, these two standards have different design philosophies. AS5100.3-2017 adopts a load factor of 1 and applies different geotechnical reduction factors for each failure mode being considered (i.e. sliding, overturning, global stability). AS4678-2002, however, applies load factors generally in accordance with AS1170, and reduction factors to material properties.

This paper presents a discussion on the two standards which are compared with each other and overseas practice. Design examples are presented for gravity walls under different loading conditions to show how the choice of standard affects design outcomes.


Dr Chris Bridges is a Technical Principal in SMEC’s Brisbane office and a technical leader in the geotechnical group. He has nearly 30 years’ experience in geotechnical design predominantly for large scale civil infrastructure and is a member of the Australian Standards Committee for the review of AS4678, earth-retaining structures.
Matt Duncanson
Senior Engineer – Materials Technology
SMEC Australia
Tiffany Parker
Senior Structural Engineer
City of Gold Coast


The City of Gold Coast (City) is the second largest local government in Australia based on its asset value and residential population. With the overwhelming majority of development occurring in the past 60 years, many structures are reaching or have exceeded their intended design life. This poses numerous challenges for the City in effectively managing their 700 bridges and major culverts, many of which are located in harsh coastal environments or within tidal waterways. Challenges faced by the City include identifying which bridge assets are in need of repair, accurately scoping engineering investigations (Level 3) in order to correctly determine cost-effective rehabilitation strategies, and ensuring completed works are of sufficient quality to provide the desired extension of remaining life.

This paper discusses how the City has overcome these challenges, providing insight from the perspective of both client and consultant. Several case studies will be reviewed, analysing the effective aspects of each project and discussing lessons learnt to enable continual improvement. Focus will be given to methods in accurate identification of the deterioration mechanisms in defective bridge components, and the importance of specifying suitable repair techniques.


Tiffany Parker is a Senior Structural Engineer acting as Asset Custodian for transport structures located within the City’s road reserves. She takes a lead engineer role in capital bridge rehabilitation and replacements projects. Her key areas of experience are bridge condition assessments, planning, scoping and procurement of bridge renewal projects within a Local Government environment.

Matt Duncanson is a Senior Engineer in SMEC’s Materials Technology team based on the Gold Coast. His key areas of experience are in the inspection, analysis, and design of rehabilitation works for concrete and steel structures. Matt has specific interest in the use of protective coatings and holds the NACE Coating Inspector 2 certification.
Dr Farhad Nabavi
Managing Director
Technocrete Consulting Engineers

The safety and serviceability of an existing bridge structure can be affected by the changes of loading conditions, deterioration of materials, damages due to extreme loading events (impact, blast, earthquake etc.) and/or design and construction errors. In long term, the load bearing capacity of the structure will be dependent on the degradation level of the concrete and steel. Thus, the performance at the structural component level over the time must be evaluated by analysing the rate of change in performance at material level. The minimum acceptable values for performance are called durability limit states.

To provide optimised asset maintenance planning and reliable repair strategy and methodology, the current condition of the structure must be precisely assessed, the mechanism and the level of the deterioration must be carefully investigated and identified, quantitative parameters must be obtained through non-destructive testing (NDT). Consequently, through data analysis, the deterioration rate and then the service life of the structure will be mathematically modelled, and the residual service life of the structure will be precisely predicted.

This paper discusses the several approach to the service life modelling based on the dominant deterioration mechanism, the level of the deterioration, and data analysis obtained by NDT results


Farhad Nabaviis a Fellow of Engineers Australia and a Chartered Professional Engineer in Civil & Structural Engineering as well as Leadership & Management. He has over 20 years’ experience in Civil and Structural Engineering as a lead designer, professional project manager, construction supervisor, and scholar. He has inspected, assessed, and provided repair and rehabilitation strategy and methodology for different types of the concrete structures in Australia and overseas.  He has published more than 25 International Journal articles and Conference papers in durability and service life of the concrete structures
Patrick Bigg
General Manager
Timber Restoration Systems

Wood Research and Development (WRD) was commissioned by Cassowary Coast Regional Council (CCRC) to design timber replacement bridges for four steel I-beam bridges with prefabricated Penta-treated glulam timber. Since 2010 WRD has worked closely with CCRC in replacing or restoring 32 of their ageing timber/steel/concrete bridges with new glulam/log girders, glulam/solid sawn deck and glulam/solid sawn kerb system. The council has now started to replace their 20 year old steel bridges as they are failing due to rusting.

The new replacement Penta Pressure treated, incised, glulam super-structure and deck has a design life of 100 years with minimal maintenance required. Seres Road Bridge Replacement – July 2018 The new superstructure can be installed on the restored substructure elements or on new pre-cast concrete abutment seats due to the lightweight of the glulam timber. The cost of the replacement with glulam girders and deck is 36% less than steel and has a 100-year life versus 20 for steel.

With the timber replacement solution, the bridge only requires a closure for 1-2 days depending on the size of the structure compared to a much longer period for many steel or concrete bridge replacement options .

This presentation will elaborate on the key issues of replacing old bridges on rural, low traffic roads and the budget constraints that come with them. 


Patrick (Pat) Bigg graduated from University of Tasmania with a Bachelor of Engineering (Civil) in 2014. Following a year in Local Government, he joined Wood Research and Development in 2016 as Timber Structures Engineer. where he has specialised in the design of bridge elements, complex connections within timber structures and Multi-frame modelling of structures. Following several stints as site engineer for bridge retrofit and renewal projects, Pat has now taken up the position of General Manager Australia for Timber Restoration Systems.
Mohsen Ranjbar-Zahedan
Phd Candidate
University of Technology Sydney
Alireza Keshavarzi,
Professor, School of Computing, Engineering and Mathematics, Centre for Infrastructure Engineering,
Western Sydney University,

Hadi Khabbaz,
Associate Professor, School of Civil and Environmental Engineering,
University of Technology Sydney

James E Ball
Associate Professor, School of Civil and Environmental Engineering
University of Technology Sydney


Pier scour is a common cause of waterway bridge failure.

In order to decrease the potential of bridge-pier-scour failure, a triangular flow diversion structure, hereafter referred as FDS, was optimised in this study as an effective countermeasure against local scouring.

An efficient statistical approach to experimental design, called Taguchi’s method, was employed to design the experimental program and to reduce the number of the experimental tests. This scientific method can be used to find the best values of the controllable factors with a minimum number of tests. According to Taguchi’s method, 25 tests were conducted to optimise the dimensions and the installation location of the proposed flow diversion structure. To compare the experimental results and to assess the effectiveness of FDS, the control and optimum tests were performed.

In this study, a 3-D printer was employed to build accurate physical models of the pier and the flow diversion structures. To measure the topography of the scoured bed after each test, a precise 3-D scanner was used. The experiments were conducted in a steady flow and under clear water scour conditions. After achieving equilibrium conditions, the bed profile was measured and the volume of the scour hole determined for each experimental test.

The results of these tests revealed the optimum dimensions of the proposed FDS and its best place of installation to achieve the maximum reduction in pier-scour. In the optimum condition, around 40% of the maximum scour depth, and 60% of the scour-hole volume were reduced. This structure can be suggested for use in real situations due to its low cost and easy installation procedure.


Mohsen Ranjbar-Zahedani is a PhD student in Hydraulic Engineering Discipline at the School of Civil and Environmental Engineering, University of Technology, Sydney (UTS). He received his ME in Hydraulic Structures from Shiraz University, Iran, in 2009. After that, he was working at Fars Regional Water Authority as a hydraulic structure specialist for seven years. He received a scholarship from UTS and started his PhD course in 2016.

Alireza Keshavarzi is a professor in Hydraulic Engineering Discipline at the School of Computing, Engineering and Mathematics, Centre for Infrastructure Engineering, Western Sydney University (WSU), Penrith, Australia. He received his ME and PhD in Hydraulic from UNSW.

Hadi Khabbaz is an Associate Professor in Geotechnical and Geo-environmental Engineering Discipline at the School of Civil and Environmental Engineering, University of Technology, Sydney (UTS).At the moment, he is Deputy Head of School Research.

James E Ball is an Associate Professor in Water and Wastewater Treatment Discipline at the School of Civil and Environmental Engineering, University of Technology, Sydney (UTS). He is the Editor Australian Rainfall and Runoff.
Armin Shoghi
Senior Structures Development Engineer
VicRoads, Metropolitan North West

This paper outlines a recent adopted strategy to protect the Napier Street Railway Bridge, in which VicRoads has implemented a new Intelligent Transport System (ITS) strategy to prevent future bridge strikes.

The Railway Bridge over Napier Street in Footscray has a clearance of 4.1 metres and has had a number of strikes by over-height vehicles, resulting in frequent temporary closures of Napier Street to traffic and posing safety risks to road users.

The Napier Street railway bridge has had more than 70 strikes in the last 7 years. The Napier Street Railway bridge is one of the highest impacted structures in Victoria, and hence VicRoads was funded to provide a strategy in preventing/reducing the number of strikes by over-height vehicles at this notorious low clearance bridge.

The paper discusses the design and construction of number of new devices implemented on site as part of the new ITS. The new system can detect any overheight vehicles approaching the bridge that have failed to follow the static signs, electronic message signs and warning line marking. At the last point, new traffic signals have been installed that stop the over height vehicles preventing them from impacting the bridge.


Armin Shoghi gained bachelors of Civil Engineering with (Hons) from Swinburne University of Technology. He is currently working at VicRoads as a Senior Structures Development Engineer. He has been involved both in delivery and development of bridge projects at the Structures team. His latest project was the delivery of the notorious Napier Street project.
David Hildebrand
Senior Officer of Asset Management
VicRoads, Western Victoria

How much confidence do we have in Level 2 Bridge Inspections?

They’re a staple of the management of structures and have been so for decades. They are amongst our first ‘informers’ of a structures condition; providing condition information on the individual structure as well as allowing us to infer the health of the network of structures we manage. But how good are they? There are numerous examples, too many to count really, of inspectors both new and the very experienced making obvious ‘misses’ in what is essentially an inspection which relies on good observation skills more than anything else. Why? And is this a problem? Do we put too much reliance on the Level 2 Inspection; should we be more pragmatic and accept their fundamental flaw; that is people; and just deal with an expected level of inaccuracy? Or do we hand this responsibility over to the machines?

This paper will explore these themes and hope to provoke conversation about an inspection that every manager of bridges relies on.


David Hildebrand has 16 years’ experience in the completing and auditing of L2 Inspections and the identification, development and sometimes delivery of Bridge Projects big and small in country Victoria.
Scott Parker
Reserves & Facilities Projects & Assets Manager
Western Bay of Plenty District Council - NEW ZEALAND

The ever increasing demand to extend and develop new shared use cycleway networks place significant capital costs on to local Council’s.

Where budgets for such projects are severely constrained, significant savings can be made by using refurbished and modified pre-loved shipping container “flat-rack” transportation platforms. Innovative thinking is often needed to achieve the great outcomes sought within limited Council budgets and ever growing complexity of planning and building regulations.

Ex shipping industry Flat-Racks provide an opportunity to span small water crossings. They are also very strong, accommodating not just cycleway traffic but also contractor maintenance vehicles/machinery. Flat racks may be considered a short-term or temporary solution but they are so affordable that shorter life-span renewal may still be more cost effective over the long-term.

The presentation will provide a “show and tell” overview of two recent cycleway projects in the Western Bay of Plenty that have used Flat Racks for bridges.


Formerly an aircraft engineer with the Royal NZ Airforce, Scott has over 12 years experience of recreation/ open space projects for the Western Bay of Plenty District Council. He is heavily involved in all of the District’s cycleway projects.
Prof Alireza Keshavarzi -1
Professor, School of Computing, Engineering and Mathematics, Centre for Infrastructure Engineering
Western Sydney University
Bijan Samali
Western Sydney University


Flooding can cause collapse of bridges in many different ways. One common one is by progressively eroding river bed around and beneath of bridge piers. This process is identified as scouring process.

Different techniques have been suggested to prevent scouring; however, most of them were unsuccessful due to the increasing shear force at the bed and ultimately causing immediate bridge collapse. An investigation by the American Society of Civil Engineers reported that more than 50 percent of all bridge collapses is due to the bed scouring. Most of the previous studies were based on scour around a single pier; however, in practice, bridges are usually wide and piers comprise two or more circular piers aligned in the flow direction that together support the loading of the structure. In this study, the effect of spacing between two aligned bridge piers on maximum scour was investigated experimentally under clear water scour conditions.

This paper presents new guidelines to design bridges considering diameter and distance of the pier. This approach minimize scouring depth at upstream of the front pier during flood events. Also two equations have been developed to predict the maximum scour depth at upstream of both front and rear piers as a function of the spacing between the piers, referred to as a pier-spacing factor.


Alireza Keshavarzi is a professor in Hydraulic Engineering Discipline at the School of Computing, Engineering and Mathematics, Centre for Infrastructure Engineering, Western Sydney University (WSU), Penrith, Australia. He received his ME and PhD in Hydraulic from UNSW.

Bijan Samali is a Professor at Western Sydney University.
Prof Alireza Keshavarzi -2
Professor, School of Computing, Engineering and Mathematics, Centre for Infrastructure Engineering
Western Sydney University
Bijan Samali
Western Sydney University


Culverts are small bridges which are built at locations where a waterway crosses a road or railway and limits flow passage. Culverts may be single or multi barrels with box, circular or elliptical openings.

One of the problems that may occur in flood events is blockage with debris at the inlet of culverts. Blockage at the inlet of a culvert commonly occurs due to transport of debris and accumulation during flood events. The blockage at the inlet modifies flow condition and may overflow the structure and may result in culvert failure. Despite this, the impacts of blockage on culvert hydraulics and downstream waterways have not received consideration in the literature.

The purpose of this paper is to alleviate this deficiency by reporting on an examination into scouring at the outlet of partially blocked culverts.

Experimental tests were conducted under steady flow to find a relation between maximum scour depth, blockage ratio and flow features. In this study, both non-blocked and partially blocked conditions were considered. Analysis of experimental tests showed that the dimension of scour hole increased with partially blocked when compared to non-blocked culverts. Furthermore, maximum depth of scouring at blocked condition occurs at the distance closer to culvert outlet in comparison with no blocking condition.


Alireza Keshavarzi is a professor in Hydraulic Engineering Discipline at the School of Computing, Engineering and Mathematics, Centre for Infrastructure Engineering, Western Sydney University (WSU), Penrith, Australia. He received his ME and PhD in Hydraulic from UNSW.

Bijan Samali is a Professor at Western Sydney University.
Andrew La Spina
Timber Structures Engineer
Wood Research and Development

A trend across North America and now into New Zealand and Australia is the conversion of old unused railway corridors into a scenic rail trails for pedestrians and cyclists to use. One of the attractions of a rail trail can be the majestic timber bridges that cross over creeks, gullies and roads. In most cases the bridges require a significant amount of rehabilitation work in order to make them safe and compliant to support pedestrian loads.

Jimmy Gully Pedestrian Bridge crosses Jimmy Gully along the Brisbane Valley Rail Trail (BVRT) near Harlin, Queensland. An extensive inspection of Jimmy Gully Bridge was completed by Wood Research and Development (WRD) technicians using non-destructive testing methods such as compression wave technology analysis (Stress Wave Timer-SWT).

WRD engineers determined that Jimmy Gully Bridge required a new structure and deck system along with several of the substructure elements requiring repair works using high strength fibres. It was designed with a new pentachlorophenol-treated glulam caps, girders and deck and handrail system with connecters that do not penetrate through the top surface. These greatly increased the longevity of the structure as well as reducing maintenance costs. With the treatment of the timber and the design connection details, the structure has a design life of 75-100 years with minimal continued maintenance. In addition to this Decaystop® (Borate Salt) rods were installed in the remaining hardwood elements in order to resist further deterioration of the timber caused by fungi growth.

This presentation will demonstrate how this was undertaken in timely and cost effectively by utilizing the existing substructure and installing a new lightweight pre-fabricated glulam superstructure and deck system. 


Andrew La Spina BE (Civil) began work with WRD as a Timber Structures Engineer. His roles within the engineering division are; to conduct and oversee certified Level II and III inspections of timber structures, compute preliminary design and analysis reports of timber bridges and drawing reviews of construction plans for timber bridges projects throughout Australia. On this project Andrew was heavily involved with the design process, assisted with the construction drawings, assisted the construction company with project management and undertook the final inspection of the newly constructed bridge.
Stephen Richards
Manager Contracts & Client Relations
Wood Research and Development

Nillumbik Shire Council (NSC) (the Green Wedge Shire) in outer north east metropolitan Melbourne had determined in 2015 the need to refurbish or replace the Diamond Street bridge (Eltham), it’s last timber road bridge in the urban area of the Shire. Wood Research and Development (WRD) were commissioned to conduct a condition assessment of the bridge then produce a preliminary design and cost estimate for refurbishment. Following confirmation by NSC that the refurbishment was expected to cost less than a new bridge at that location, WRD then completed a detailed design for the refurbishment and restoration of the load rating to T44. The bridge was already down-rated to 12 tonnes prior to WRD’s involvement.

During the inspection of the bridge, it was recognised that the bridge had an unusual superstructure arrangement, a stress laminated deck and significant reinforced concrete packers atop the prior timber headstocks and piles bents (no girders in this case).

Upon further investigation during the design process, it was recognised the laminations in the stress lam deck were penta treated coastal Douglas fir. Inquiries with the client, NSC revealed that the deck was installed 25 years earlier during the last upgrade of the bridge. This deck material was confirmed during the construction phase to be in as new condition apart from very minor decay where the installing contractor had drilled vertical holes into bright wood along each edge of the deck when installing the guard rail system.

This paper will focus on the longevity of the treated timber deck as well as the unique design of the prior upgrade and the recently completed restoration.


Stephen Richards, BE (Civil) has worked in Local Government for 24 years with 9 years in civil project design and delivery and 15 years in the management of municipal works, construction, special projects and asset management. He joined Timber Restoration Systems in 2010 as Operations Manager and moved to Wood Research and Development in 2015 as Manager Contracts. In this time Stephen has managed the delivery of contracts valued between $57k and $2.3m.
Dr Dan Tingley -1
Senior Engineer
Wood Research and Development. USA

The traditional method for identifying and assessing internal decay in timber bridges has been bore-sounding where a small hole is drilled into a member and a probe is inserted to measure the cavity size. This testing method is damaging to the timber, and it creates a path for water, insects and oxygen to enter the member. Advanced non-destructive testing methods exist that can be more effective in locating decay without damaging the timber. One of main and most effective techniques is using EPHOD® (Electronic Pulse Highlight and Outline Diagnostic) compression wave technology. The EPHOD® equipment is utilized to complete stress wave measurements along with other WRD techniques to locate internal decay in a non-destructive nature. The machine used in these types of situations is called a Stress Wave Timing (SWT).

Wood Research and Development (WRD) was commissioned by Stantec to complete a Level II Bridge Inspection of the Keystone Wye Interchange which consisted of two timber highway bridges, the 411 – Lower Bridge and the 412 – Arch Bridge. The interchange, located near Keystone South Dakota USA and is part of the entrance to the historic Mt. Rushmore National Memorial. Non-destructive testing, including Stress-Wave Timer testing, was implemented to determine the state of the main timber structural elements within these two bridges.

This presentation will elaborate further on the key issues of inspecting old timber bridges and keeping the structural integrity of the bridge at the forefront.


Dr Dan Tingley, BScFE, M.Sc.C.E, Ph.D. (wood technology and structural engineering), has worked in the wood products field for over 40 years. He currently serves as the Senior Engineer for Wood Research and Development and Advanced Research and Development and makes his base in Portland, Oregon. Tingley holds over 40 patents worldwide and has over 125 referred and non-referred publications. He specializes in timber structures design and restoration and is currently acting as a senior engineer providing oversight on 20 timber bridge restoration projects worldwide.
Dr Dan Tingley -2
Senior Engineer
Wood Research and Development. USA

A major flood event in early 2018 washed out the Flaggy Creek Bridge at Mona Mona Qld. An emergency, adjustable span, glulam bridge was upgraded to the required vehicle loading, shipped to the site and installed to quickly open the road again for use by local traffic.

Considering that the former bridge at the Flaggy Creek crossing was washed out by a 1 in 60 year (0.0167% a.r.i.) flood event and that the damage was caused by a fast flowing stream laden with large fallen logs and stumps; the design of the temporary structure presented a number of challenges. The Design matters requiring resolution were the structural capacity under traffic, the structural capacity whilst submerged and the hold-down systems necessary to satisfy the loading demands. These issues are often commonplace in bridge design however different considerations were required due to the temporary nature of the structure and the need to be able to remove it at the conclusion of its use. WRD’s objective here was to ensure the temporary bridge would survive until the client’s ultimate bridge solution could be funded, tendered, designed and constructed.

This presentation will cover the design, upgrading and installation of the adjustable length emergency bridge span.


Dr Dan Tingley, BScFE, M.Sc.C.E, Ph.D. (wood technology and structural engineering), has worked in the wood products field for over 40 years. He currently serves as the Senior Engineer for Wood Research and Development and Advanced Research and Development and makes his base in Portland, Oregon. Tingley holds over 40 patents worldwide and has over 125 referred and non-referred publications. He specializes in timber structures design and restoration and is currently acting as a senior engineer providing oversight on 20 timber bridge restoration projects worldwide.