Study Finds Recycled Tire Materials Can Be Reused In Concrete

Rubber and polymer fibers from discarded car tires could soon be used in major civil engineering projects such as bridges, tunnels and earthquake-resistant buildings, researchers believe.

A European Union (EU) funded project led by experts at the University of Sheffield and Imperial College London, working in association with the European Tyre Recyclers Association (ETRA), has demonstrated through extensive experimental work and trials that rubber, steel and textile fibers from tires can be reused in concrete.

Results of this work, known as the Anagennisi project, were presented at a special dissemination event at Imperial College London last month.

The project team found that recycled rubber will allow buildings and other structures to flex up to 10 per cent along their length – 50 times more than structures made from conventional concrete. The team researchers are hoping to prove that tire rubber can make concrete flexible enough to be an advantage in areas of seismic activity as well as in bridges. It hopes this product will be available by the end of this decade.

Tire wire, which is exceptionally strong, can also be blended with other steel fibers to increase the flexural strength of concrete, researchers found. These fibers are also much thinner than conventional steel fibers, which means there are more in the concrete, helping to control cracks at the micro level, according to project reports.

In other research, the project has already worked on conversion of steel wire found in tires into concrete that is being used commercially for floors of industrial buildings.

A third component, textile polymer fibers, used primarily as reinforcement in passenger tires, is also of high quality and strength and can be used to control cracking at the early stages of concrete curing, when the material is still plastic. Sheffield researchers found that textiles fibers help prevent explosive concrete spalling (crumbling, breaking up) during fires, and applications are being developed for tunnels and buildings.

According to University of Sheffield engineering professor Kypus Pilakoutas, the rubber-infused concrete will be tested on a shaking table next year with the aim of getting it to market by 2020. “With polymer fiber, we are doing experiments on restrained shrinkage, and fire tests,” Pilakoutas said.

Plans are now being formulated to use the new concrete material in seismic resistant buildings, vibration isolation and bridge bearings. As part of the EU-funded Anagennisi project, demonstration projects will be undertaken in several countries to convince contractors and infrastructure owners of the benefits.

The first processing facility for tire wire has been established in the UK by project partner, Twincon Ltd, as part of another EU Eco-innovation project which works in parallel to Anagennisi. With demand currently outstripping supply in the EU, there are plans to scale up production by establishing processing facilities at other recycling plants around Europe.

© Scrap Tire News, August 2015