About 35% of landfill waste is generated by the construction industry, with millions of tons of debris and rubble disposed of each year around the globe. Similarly, around one billion automobile tires go to waste every year. Most of such tires end up in landfills causing a wide range of issues. On that note, an??published by the United Nations Environment Programme explains that “when significant quantities of municipal or industrial solid waste are dumped or burned in the open, the adverse impacts on air, surface and groundwater, soil and the coastal and marine environment, and thus indirectly on public health, can be severe.”
On the other hand, concrete is a widely used material but traditionally consumes natural resources like cement, sand, and rocks, significantly affecting the environment. One possible avenue to reduce waste and save natural resources is to upcycle the construction and demolition waste and waste rubber tires into concrete. Recycling waste materials to replace aggregates in the production process of concrete is usually considered an alternative to overcome waste-related problems. However, up to an 85% drop in the concrete’s strength occurs when waste tires are used as aggregates in concrete production.
The technique to achieve rubber concrete properties like traditional concrete is now available. Thanks to a team from the School of Engineering at?, a member institution of the?United Nations Academic Impact (UNAI)?in Australia, we are closer to reducing the amount of construction and rubber tire waste in landfills. Inspired by the global waste problem, the team developed a new technology to manufacture concrete made from recycled materials, with a more robust and durable product than the traditional one. This new method for casting prefabricated concrete products increases strength by up to 35%.
Professor Yufei Wu led the Rubberized Concrete Processing Technology (RCP-Tech) development and said it offered an efficient and inexpensive solution. “This technology can significantly improve the strength, hardness, and durability of any concrete material, such as rubber concrete, recycled aggregate concrete, and even ordinary concrete. The technology can also save cement quantity and total material costs compared with conventional concrete for the same concrete strength,” he commented. The method combines a mix of coarse and fine aggregates with rubber tire waste, cement, and water.
The result of it is then compressed to its minimum volume using pressure in specially designed molds. “By enhancing the properties of the recycled waste without using any additional materials, we have developed a feasible and practical solution that addresses the performance issues affiliated with waste recycling in concrete,” Professor Wu explained. In this study, river sand, tap water, and ordinary cement were used to prepare all the concrete mixes that were analyzed as part of this research project, which focused on manufacturing eco-friendly and ‘green’ concrete for a far more sustainable construction industry.
As outlined in the document?, issued by the United Nations Industrial Development Organization, there is actually a noticeable and “growing demand for services and products directed towards cleaner technologies, reductions in environmental risk, and resource management (including recycling and resource recovery).” Therefore, the results of this research project are aligned with the goal of not only creating a construction industry that is more environmentally conscious but also creating a real impact in the management of waste, which is a concern worldwide.
RMIT Postdoctoral researcher and RCP-Tech co-creator Dr. S.M.S. Kazmi said the team of engineers is now looking to partner with the precast concrete industry in order to be able to manufacture and test products like blocks, 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. This would also be a leading example of collaboration between academia and the industry sector, with the??in mind.
