INNOVATION IN CONSTRUCTION
The construction industry is looking at innovations as a way to conserve scarce resources and building environment-friendly structures. One way to accomplish this objective is to use end-of-life tyres to save on construction materials but without compromising on quality, safety and durability.
Prof Dr Kypros Pilakoutas, Professor of Construction Innovation at the University of Sheffield, said in an interview that construction industry is probably the largest user of materials. These materials are required to have a wide range of properties ranging from structural strength, to colour, conductivity and durability.
“Tyres are highly engineered with extremely high quality materials and the recycling or re-use of those materials from end-of-life tyres (ELT) makes sense,” he told Tyre Asia. Tyres comprise 80 per cent rubber, reinforced with 15 per cent steel and 5 per cent textile fibre.
“In the first instance, we looked at the steel wire that was extracted from tyres mechanically using the shredding process. The wires are very strong and similar to wires that we use to reinforce concrete against tensile strain that leads to cracks,” he said.
However, the researchers found some problem in extracting the wires from the tyres. “The problem we found was that the steel wires extracted from ELTs are tangled, contaminated and variable in length. When mixed in concrete, they create agglomeration (balling) issues, damaging the concrete,” he explained.
After careful consideration, his team of researchers decided to take out the wires that caused problems, and found that the shorter wires were not much effective. This was initially done manually, but had led to taking a patent over this process.
With a lot more research, after the patent was filed, the researchers have managed to develop many applications for the fibre, including industrial floors (slabs on grade), roads (roller compacted concrete), tunnels and slope stabilisation (spayed concrete).
“Now we are also looking at the use of rubber in concrete to develop flexible elements and the use of polymer for crack control and prevention of spalling (crumbling and breaking up) during fire, said Dr Pilakoutas, who is currently heading several research projects and holds over 30 patents.
Besides being the Construction Innovation Professor, he is also the Manager of the Centre for Cement and Concrete and the Chairman of the Concrete Research Group.
TA News Bureau
(Full text in TA, June/July)