Utilisation of CO₂ Concrete for the Production of a Living Lab

The methodology of carbon-conditioning involves the sequestration of carbon dioxide (CO₂) into recycled concrete aggregate in order to acquire a concrete know as CO₂ concrete. Carbon-conditioning not only increases the properties of recycled aggregate and recycled aggregate concrete but also entraps carbon dioxide which otherwise would be released into the earth’s atmosphere. The mechanism by which the recycled aggregate is improved involves the conversion of calcium hydroxide, found in such objects as cement paste, into calcium carbonate. The smaller calcium carbonate crystals fill air voids in the weak recycled aggregate transforming the material into CO₂ aggregate. The injection of CO₂ is completed by placing recycled aggregate into a sealed chamber before exposing it pure pressurised carbon dioxide. The method accelerates the natural phenomenon of carbonation permitting recycled aggregate to be completely densified and improved. Whilst it is known that CO₂ concrete improves upon recycled aggregate concrete as a material, it is unknown if CO₂ concrete can successfully be administered into a real life application. This paper provides evidence that CO₂ concrete can indeed be utilised in a real life, living lab scenario. Four slabs of 3 by 2.6 m and 200 mm deep were placed for the implementation of cattle drinking stations. Two slabs are made up of 15% recycled aggregate CO₂ concrete whilst the remainder comprised of 100% recycled aggregate CO₂ concrete. The slabs were subjected to non-destructives tests all attaining a similar compressive strength of over 40 MPa. The slabs also experienced a visual inspection to attain the effect of the environment as well as heavy cattle damage. After two months no visual degradation has begun demonstrating the strength of CO₂ concrete. The living lab style of examination indicates that CO₂ concrete has latent characteristic exhibiting the ability to withstand tremendous loads. The examination provides evidence which showing that CO₂ concrete has the potential to be utilised on a larger scale.