Carbon-dioxide-activated bonding material with low water demand

Abstract

The production of concrete based on Portland cement consumes huge amounts of water every year, but water conservation is becoming a global concern. To address this issue, a special bonding material activated by carbon dioxide instead of water was prepared. The hardening performance, the composition and microstructure of the reaction products and the hardening mechanism of this bonding material were evaluated. It was found that the compressive strength of the material reached 78·2 MPa after the carbon-dioxide-activated curing (CDAC) process. The main reaction products were determined to be calcite and polymerised silicon dioxide gels, which formed a dense microstructure and thus contributed to the material's excellent mechanical strength. Furthermore, in this process, water is not chemically consumed and can be easily recovered during the CDAC. The results indicate that this is an ideal bonding material for buildings in water-scarce areas.