Infrastructure projects across Australia are set to reap the benefits of a new retaining wall system that is now available locally.
By the National Precast Concrete Association Australia.
|Project – Ovingham Level Crossing Removal Project
Head contractor – PTP Alliance (McConnell Dowell, Arup and Mott Macdonald with the South Australian Government’s Department for Infrastructure and Transport)
Master Precaster – The Reinforced Earth Company
A new retaining wall system is being used on a level crossing removal project within one of Adelaide’s inner suburbs, delivering significant enhancements in both construction safety and speed. The new system combines precast and in situ concrete construction to deliver a highly efficient and robust cantilever retaining wall.
National Precast Concrete Association Australia Master Precaster The Reinforced Earth Company has brought the new technology to Australia. Full-height facing panels that come complete with pre-attached perpendicular counterforts are manufactured and then delivered to site. The integrated counterforts are then jointed onsite to a structural concrete footing.
The Ovingham Level Crossing Removal Project in Adelaide, South Australia, is the first infrastructure project in Australia to try the new system.
Level crossing removals prioritised
The removal of level crossings across the country involves eliminating intersections between roads and railway lines by either elevating rail lines or lowering roads. The main objective is to reduce the risk of accidents and fatalities associated with level crossings, which are known to be high-risk areas.
There are more than 23,500 railway level crossings in Australia, according to the Australian Rail Track Corporation. Of these, 21 per cent have operational boom gates or flashing lights. The dangers are real, with around 30 fatalities every year resulting from level crossing collisions and more than 1,000 near hits annually between vehicles and trains.
Prioritising the removal of level crossings showcases commitment by Australian governments to modernising transportation infrastructure, for the betterment of communities and for the efficiency of cities. Collaborating with rail and transport authorities to plan, fund and execute these projects, governments consider factors like community impact, cost-effectiveness and environmental sustainability. The target is to enhance safety, efficiency and traffic flow across the nation.
Removed for safety and efficiency
Ovingham has long experienced significant traffic congestion due to the presence of multiple level crossings. The crossings often resulted in delays, increased accident risks and hindered emergency response times. The ageing infrastructure and growing population exacerbated the issue, necessitating a comprehensive level crossing removal project.
Jointly funded by state and federal governments, the $196 million Ovingham Level Crossing Removal Project is removing the level crossing at Torrens Road, Ovingham and involves construction of a new 180-metre-long bridge that connects into two approach ramps, with three lanes city-bound and two outbound lanes. Executed in multiple phases, innovative engineering techniques have been employed across the project to ensure minimal disruption and to maintain safety during the construction process.
With an average of 21,300 vehicles passing through the level crossing daily, its removal will significantly impact safety, freight productivity and connectivity and traffic flow in the area.
New heights for retaining wall technology
As a fundamental component of civil engineering and construction for centuries, retaining walls aid in managing slopes, preventing erosion and creating usable spaces on uneven terrain. Advancements in materials, and design and construction techniques have revolutionised the field of retaining wall technology, leading to structures that are not only highly functional but also aesthetically pleasing.
Never before used in Australia but widely used across America and Europe, The Reinforced Earth Company’s TechWall system presents a new, innovative concept for optimising retaining walls. Known as a counterfort retaining wall system, it consists of full-height wall facing units which can easily feature architectural detailing and patterns. Panels are delivered with counterforts pre-cast on the rear side and protruding rebar dowels from their bases. Onsite, the footing is formed, reinforcement is placed, and the panel dowels are tied in to provide the necessary embedment and development lengths. The cast-in-place footing is then poured, securing the panels in place and increasing the effectiveness of the load transfer mechanism to the ground.
Riccardo Musella, The Reinforced Earth Company’s managing director in Australia, says the system’s full height monolithic units mean no soil reinforcement is needed and it is a simple and economic replacement for traditional cast-in-place cantilever wall designs.
“This system will revolutionise retaining walls,” says Musella. “It is perfect for narrow cut situations or applications with extreme obstructions within the fill zone, and offers complete aesthetic versatility, with facing panels allowing for a wide variety of surface patterns and texture if desired.”
Improved safety gets the thumbs up
The project has received resounding feedback from the community, praising the improved safety and convenience brought about by the upgrades and impressed by the walls, bridge and plaza, all of which look like works of art thanks to the stunning urban design that translates Aboriginal stories into visual elements.
Serving as a blueprint for similar infrastructure projects, the Ovingham Level Crossing Removal Project is enhancing safety, connectivity and overall quality of life in urban areas. Its success highlights the importance of thorough planning, stakeholder engagement and innovative construction techniques in achieving project objectives. It is a project that demonstrates the potential for transformative infrastructure projects to enhance communities and lays the groundwork for future urban development.
Musella says he is very proud that his company had the opportunity to work with the PTP Alliance to bring this technology to Australia. This partnership has proven highly successful, as evidenced by the notable achievements on the Ovingham Level Crossing Removal Project.