Cleaner, stronger, harder: New tech improves sustainable concrete

Researchers have developed a new technology to manufacture concrete made from recycled materials that is stronger and more durable than the traditional product.

Recycled concrete aggregates made with everything from coffee cups to building rubble offer huge environmental benefits, from reducing landfill and CO₂emissions, to saving natural resources and boosting the circular economy.

Despite ongoing improvements however, challenges with matching the strength and durability of traditional concrete have hindered the practical application of these sustainable alternatives.

Now researchers from RMIT have developed a new method for casting prefabricated concrete products made with rubber tyres and construction and demolition waste that are up to 35% stronger than traditional concrete.

Professor Yufei Wu from the School of Engineering led the development of the Rubberized Concrete Processing Technology (RCP-Tech) and said it offered an efficient and inexpensive solution.

“This technology can be used to significantly improve the strength, hardness and durability of any type of concrete material, such as rubber concrete, recycled aggregate concrete, and even ordinary concrete,” he said.

The concrete is compressed in a customised mould, improving strength and durability.

The method involves combining a mix of course and fine aggregates with rubber tyre waste, cement and water which is then compressed to its minimum volume using pressure in a customised mould.

“By enhancing the properties of the recycled waste without the use of any additional materials, we have developed a feasible and practical solution that addresses the performance issues affiliated with waste recycling in concrete,” Wu said.

Rubber from waste tyres is the cause of significant health, environmental and land fill problems worldwide owing to its chemical, flammable and non-decomposable nature.

From 2015-16 Australia generated around 450,000 tonnes of waste rubber, 63% of which was sent to stockpiles or landfills and Victoria alone produces the equivalent volume of the Eureka Tower every four years.

PhD researcher and RCP-Tech co-creator, Syed Kazmi, said the team was now looking to partner with the precast concrete industry to manufacture and test prototypes of products like blocks and roadside barriers, wall panels, beams and slabs.

“The technology can be easily applied in the precast concrete industry and requires very little change to existing manufacturing processes with the addition of just one extra step in the final stage of production,” he said.

Kazmi and fellow PhD researcher Muhammad Munir presented the technology at the City of Melbourne Open Innovation Competition 2020 where they were finalists. They were also awarded the RMIT LaunchHUB prize for their work.

The findings, Application of waste tire rubber and recycled aggregates in concrete products: A new compression casting approach are published in the journal Resources, Conservation and Recycling (DOI:10.1016/j.resconrec.2020.105353).

Story: Grace Taylor

Technology

28 January 2021

Return to RMIT News

Technology

28 January 2021

Research
Property & Construction

Engage

Contact RMIT News

Find an expert

Study with us

Research at RMIT

Related News

‘Incredibly resilient’ nylon device creates electricity under tonnes of pressure

RMIT University researchers have developed a flexible nylon-film device that generates electricity from compression and keeps working even after being run over by a car multiple times, opening the door to self-powered sensors on our roads and other electronic devices.

Aussie bushfire prevention tech goes global

A powerline fault detection system invented at RMIT is being rolled out globally thanks to AUD $50 million in new funding.

New carbon-conversion technology could turn emissions into jet fuel

RMIT researchers have developed a carbon conversion technology that may one day help turn industrial emissions into jet fuel, by simplifying how carbon dioxide is recycled.

5G home internet challenges NBN, but mass shift still a way off: study

Most Australians who have 5G are content with it, yet few actively seek it out or plan to switch in the short term, a study from RMIT University has found.

Acknowledgement of Country

RMIT University acknowledges the people of the Woi wurrung and Boon wurrung language groups of the eastern Kulin Nation on whose unceded lands we conduct the business of the University. RMIT University respectfully acknowledges their Ancestors and Elders, past and present. RMIT also acknowledges the Traditional Custodians and their Ancestors of the lands and waters across Australia where we conduct our business - Artwork 'Sentient' by Hollie Johnson, Gunaikurnai and Monero Ngarigo.

More information

Cleaner, stronger, harder: New tech improves sustainable concrete