Research: Recycled Tires Aid Concrete Fire Resistance
Researchers from the Department of Civil and Structural Engineering at The University of Sheffield (South Yorkshire, England) have reportedly found a new way ot protecting concrete from fire damage.
The team has tested a technique of using fibers extracted from recycled tires and adding them to the concrete mix. The process, according to researchers, has shown to reduce the concrete’s tendency to spall.
Though some modern projects have used concrete that includes polypropylene to protect against fire spalling, this research set out to show that that the fibers do not need to be made from raw materials, but instead can be used from recycled tires.
“We’ve shown that these recycled fibers do an equivalent job to ‘virgin’ PP fibers, which require lots of energy and resources to produce,” explains lead author Shan-Shan Huang.
“Using waste materials in this way is less expensive, and better for the planet.”
The idea behind using PP is that the fibers melt under intense heat, leaving networks of tiny “channels” in the concrete. Moisture that’s trapped in the concrete can then escape, rather than become trapped and “explode” out of the concrete, causing the spalling.
“Because the [fibers] are so small, they don’t affect the strength or the stiffness of the concrete,” says Huang.
“Their only job is to melt when heat becomes intense. Concrete is a brittle material, so will break out relatively easily without having these [fibers] help reducing the pressure within the concrete.”
According to the university, the team plans to continue testing the material with different ratios of the fibers to concrete, and also using different types of concrete. They also plan to find out more about how the materials react to heat at the microstructure level.