Media release

From: Flinders University

Flinders University researchers are turning mining waste into a powerful tool for sustainable construction – proving that superior construction materials can be developed from unlikely sources.

In a major building block that could help reshape the future of construction materials, Dr Aliakbar Gholampour from Flinders University’s College of Science and Engineering has uncovered promising applications for a rare earth by-product in concrete production.

The study focuses on Delithiated β-spodumene (DβS), a by-product of lithium refining, which exhibits pozzolanic properties – meaning it reacts chemically to enhance the strength and durability of concrete. The research shows that when used in geopolymer binders, DβS can significantly improve mechanical performance and long-term resilience.

“By examining the microstructural behaviour of DβS-based geopolymers under varying alkaline activator ratios, we’ve gained critical insights into its suitability as a sustainable concrete ingredient,” says Dr Gholampour.

Conventional concrete is the world’s most manufactured item and most widely used construction material, with 25 billion tonnes used every year – but it consumes about 30% of non-renewable natural resources, emitting about 8% of atmospheric greenhouse gases and comprising up to 50% of landfill.

Creating an environmentally-friendly alternative to conventional concrete, without sacrificing either strength or durability, will substantially reduce the consumption of natural resources, waste and emissions.

The findings of the new studies by Dr Gholampour and his team provide insight to the effective incorporation of DβS as an alternative ingredient to fly ash (a coal combustion by-product) in the creation of geopolymer binders. It also identifies the optimal alkaline ratio range for use in geopolymer.

“This approach not only enhances mechanical properties and durability of geopolymer concrete, but also addresses a growing environmental concern by diverting DβS from landfill,” says Dr Gholampour.

“With lithium refining responsible for generating increased volumes of DβS, the capability to reuse this in construction offers a sustainable solution that will reduce industrial waste, prevent potential soil and groundwater contamination, and support circular economic practices in the mining and building sectors.”

The findings –  Advanced characterization of ambient-cured geopolymer paste with delithiated β-Spodumene: effect of Na2SiO3–to–NaOH ratio on performance and microstructure” and “Reactions, phase evolution, and microstructure of ambient-cured geopolymer with delithiated β-spodumene”, by Mohammad Kiamahalleh, Aliakbar Gholampour, Youhong Tang and Tuan Ngo – have been published in Materials and Structures journal and Journal of Materials in Civil Engineering.

This builds on an important series of research papers published this year by Dr Gholampour’s research team – from testing alternative compositions of improved construction materials to the more effective use of 3D printing of concrete.

These include: Effect of polypropylene and polyvinyl alcohol fibres on mechanical behaviour and durability of geopolymers containing lead slag: Testing, optimisation and life cycle assessment (published in Construction and Building Materials journal);  An interpretable XGBoost-SHAP machine learning model for reliable prediction of mechanical properties in waste foundry sand-based eco-friendly concrete (published in Results in Engineering journal); and A reliable hybrid extreme learning machine-metaheuristic framework for enhanced strength prediction of 3D-printed fibre-reinforced concrete (published in Results in Engineering journal).

The authors also joined experts from Vietnam, Korea and Algeria to publish Designing a robust extreme gradient boosting model with SHAP-based interpretation for predicting carbonation depth in recycled aggregate concrete’ in Artificial Intelligence Review this month.

Together, these studies demonstrate a comprehensive and forward-thinking approach to sustainable construction innovation.

From repurposing locally-sourced industrial by-products such as DβS to integrating advanced machine learning models and 3D printing technologies, Dr Gholampour’s research team is paving the way for smarter, greener and more resilient construction materials and technologies.

“These findings not only contribute to reducing environmental impact and resource consumption but also enhance the performance, predictability and adaptability of next-generation concrete systems,” says Dr Gholampour.