Rethinking waste to build a greener Victoria

TONY ALOISIO is Ecologiq’s Director and a passionate advocate for building sustainable infrastructure.

Recycled glass bottles and crushed concrete will help shape the future of transport infrastructure in Victoria.

Almost 2.9 million tonnes of recycled and reused content were used across the state’s major road and rail projects in the last financial year, and that is just the beginning.

The Victorian Government has created the Ecologiq initiative to drive change, as it works with transport projects to optimise the use of recycled and reused materials to reduce waste.

Ecologiq is fulfilling this mission by supporting the implementation of the Recycled First policy, which requires bidders on transport projects to demonstrate how they will maximise their use of recycled and reused materials.

Recycled First supports the government’s circular economy strategy, Recycling Victoria, which sets out a 10-year plan to overhaul the state’s recycling sector, grow domestic recycling capabilities and fuel innovation.

Ecologiq’s Director Tony Aloisio said the Big Build’s 165 projects are a pivotal opportunity to review the state’s approach to waste management.

“Ecologiq will help give new life to waste products while supporting the revitalisation of Victoria’s recycling sector,”
Mr Aloisio said.

The waste and recycling industry had been troubled in recent years, with China’s move to restrict the import of low-quality mixed recyclables in 2018 causing instability in global markets and resulting in waste stockpiles.

By 2046, Victoria is forecast to generate 40 percent more waste per year than in 2017-18.

“The Recycled First policy is a great way to measure our progress, as it requires contractors to integrate recyclables and report on types and quantities used,” Mr Aloisio said.

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“This will help us find areas for improvement so we can vastly exceed the current figure of 2.9 million tonnes of recycled content a year.”

Crushing it

Crushed concrete’s versatility, durability under compression and cost-effectiveness make it perfect for re-use.

Crushed concrete sourced from demolition works, returned loads and other infrastructure activities is a proven and well-established product that exemplifies the benefits of using recycled products

“It is readily available and can be reused for new applications – it doesn’t need to be re-engineered to be effective,”
Mr Aloisio said.

Crushed concrete is used in an array of applications, including as a crushed rock replacement.

Depending on the class of crushed rock specified, from 5% to 100% of crushed concrete can be used as a replacement, while for glass fines in crushed rock, between 5% and up to 50% can be used.

The nine-kilometre Mordialloc Freeway project is a great example of how a project has used crushed recycled concrete to exceed its sustainability targets.

So far, more than 100,000 tonnes of recycled crushed concrete have been incorporated in the road base and more than 400,000 tonnes used in under road drainage.

“These sort of recycling initiatives can lead to significant savings,” Mr Aloisio said.

“Applying recycled crushed concrete utilises a high-performance waste material that would otherwise go to landfill and avoids the cost of quarrying virgin materials.”

Cheers to recycled glass

Victoria recovers three-quarters of the 250,000 tonnes of glass waste it generates every year. While almost half of this is recycled back into glass cullet for manufacturing, the other half comprises glass fines that can have many construction applications.

The use of recycled glass sand to replace its quarried equivalent is increasingly common in transport projects.

In intermediate asphalt layer mixes for road pavement, as much as half of the natural sand required can be replaced with glass fines. Recycled crushed glass can be used as a partial fine aggregate replacement in concrete, while varying levels of the material can be used in granular subbase and road-base. In non-structural general concrete paving, up to 30% glass fines can be used as a natural sand replacement.

In 2019, the Kororoit Creek Road Level Crossing Removal Project used recycled glass as bedding fill for combined service routes, as well as backfill for drainage piping.

The recycled sand made from crushed glass provided a significant cost saving, diverted a significant amount of material from landfill and led to a uniform Metro Train Melbourne specification for the application.

The $1.8 billion Western Roads Upgrade – which transformed eight key roads in Melbourne’s west, improving hundreds of kilometres of road over 20 years – is an outstanding example of recyclables in action.

Around 190 million glass bottles were used to surface these roads across the western suburbs.

Mr Aloisio said these examples highlight the enormous progress that has been made to incorporate recycled crushed glass into infrastructure construction.

“It’s a tried and tested way to boost sustainability and satisfy Recycled First policy principles,” he said.

“Industry research is underway to harmonise specifications for how recycled glass should be processed for specific applications, particularly around managing contaminants and odour.”

Swinburne University, in partnership with various government agencies and Metro Trains, are investigating the use of glass fines blended with other materials such as crushed concrete in track formation.

This will lead to more quality consistence, improve the reliability of applications, create market confidence and potentially lead to increases in allowable limits in some uses.

Future opportunities in construction materials

While we have detailed examples and growth opportunities for known and emerging products like crushed concrete and recycled crushed glass sand, the government’s recycling objectives being driven by Ecologiq encourage organisations to find innovative solutions that encompass recycling.

“We have an opportunity to identify new ways to recycle and reuse waste construction materials, such as excavated rock and spoil, which present a great challenge to the industry,” Mr Aloisio said.

“Organisations that are nimble and agile and can find innovative solutions to these issues will help steer the industry to a greener future.”

The recent release of Ecologiq’s reference guides for recycled materials in rail, road and ancillary infrastructure will help support the Recycled First policy’s implementation.

The guides offer a concise overview of industry standards and specifications for reused and recycled materials.

Mr Aloisio is confident the guides will help contractors explore easy ways to meet Recycled First requirements.

“While there are exciting new recycled materials and products being developed all the time, teams can optimise the many materials already approved for use right now,” he said.

For a copy of the Reference Guides or to find out more, email: ecologiq@roadprojects.vic.gov.au

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