Discarded plastic bottles could one day be used to build stronger, more flexible concrete structures, according to a new study.
MIT undergraduate students have found that, by exposing plastic flakes to small, harmless doses of gamma radiation, then pulverizing the flakes into a fine powder, they can mix the plastic with cement paste to produce concrete that is up to 20% stronger than conventional concrete.
Concrete is, after water, the second most widely used material on the planet. The manufacturing of concrete generates about 4.5% of the world’s human-induced carbon dioxide emissions. Replacing even a small portion of concrete with irradiated plastic could thus help reduce the cement industry’s global carbon footprint.
Reusing plastics as concrete additives could also redirect old water and soda bottles, the bulk of which would otherwise end up in a landfill.
Going forward, the team is planning to experiment with different types of plastics, along with various doses of gamma radiation, to determine their effects on concrete.
For now, they have found that substituting about 1.5% of concrete with irradiated plastic can significantly improve its strength.
While that may seem like a small fraction, implemented on a global scale, replacing even that amount of concrete could have a significant impact.
Image credit: MIT News