Much has been said about circularity in the construction industry. Inspired by nature, the circular economy works in a continuous process of production, resorption and recycling, self-managing and naturally regulating itself, where waste can turn into supplies for the production of new products. It is a very interesting concept, but it faces some practical difficulties in everyday life, whether in the demolition / disassembly process, or in the correct disposal of materials and waste; but mostly due to the lack of technologies available to recycle or give new use to construction materials. About 40% of all waste generated on Planet Earth comes from civil construction, and a good part of it could be recycled. Concrete is an especially important material because of its large carbon footprint in production, its ubiquity and massive use, and also because of the difficulty of recycling or reusing it.
Until recently, we have been able to crush demolished concrete structures which produce aggregate material consisting of smaller parts of concrete. This, in turn, often ends up being used for restricted processes such as down cycling (in materials with a more limited range of uses than the original material). Through this simple crushing process, the fragments end up used as base materials for structures such as roads, or other similar uses. Due to the low quality of the secondary aggregates, their exchange rate for the primary material is limited to around 30% - a very unsatisfactory level to ensure the desired quality of concrete, due to the excessive amounts of cement and chemical additives it contains.
