New method allows concrete to be recycled by adding woodSiobhan Treacy | February 20, 2020
Researchers from the Institute of Industrial Science at the University of Tokyo created a new procedure for recycling concrete by adding discarded wood.
The correct proportion of wood and concrete inputs yields an entirely new building material, with bending strength that is superior to the original concrete. This would reduce construction costs and cut carbon emissions from concrete production.
Concrete has two parts: aggregate, which is made of gravel and stone, and cement. One recycling option is to reuse the aggregate, but this is unsustainable because the problem is in new concrete production - the new method adjusts the mixture proportion, pressure, temperature, pressing duration and water content.
Wood is rigid due to lignin. In the new material, lignin fills gaps in the concrete and functions as an adhesive with waste concrete powered when heated. The material strength improved in higher temperatures and pressure during pressing. It is also likely to be biodegradable because concrete waste is attached to a wood component.
The team says that the new method could be extended to other kinds of discarded plant matter. A paper on this new procedure will be published in the Sixth International Conference on Construction Materials.