EARLY-AGE CARBONATION OF CALCIUM SILICATE HYDRATE (C-S-H) AND ITS ABILITY FOR CO2 SEQUESTRATION IN CONCRETE

Abstract

The research trend in the last years on early-age carbonation of calcium silicate hydrate, main component phase of Portland cement, in association with the process of permanent storage of CO2 in carbonates, reducing its emissions in the atmosphere, was the objective of ongoing work. Using sodium bicarbonate (NaHCO3) in the mixture of cementitious materials, partially replacing the cement (between 7-21 %), curing the fresh concrete was made in an early-age period. Very high value of compressive strength (43.1 MPa) was obtained very quickly being measured in the first stage of investigating the sample characteristics (after 8 hours), the reference sample reaching 30.8 MPa after 7 days and 43.3 MPa after 28 days.

Keywords

• calcium silicate hydrate
• Portland cement
• early-age
• CO2 sequestration
• sodium bicarbonate
• compressive strength