A maturity approach to estimate compressive strength development of CO2-cured concrete blocks

An alternative CO2 curing method for precast concrete products has been proposed in order to achieve rapid strength development at early age, as well as to capture and store greenhouse gas (CO2). In this paper, an experimental study for the development of a maturity approach is presented to estimate the strength development of carbonated concrete blocks. In order to promote the use of industrial flue gas containing CO2, a flow-through CO2 curing regime at ambient pressure and temperature was employed using different atmospheric conditions, such as various CO2 concentrations, RH values and gas flow rates. The experimental results showed that the compressive strength or maturity of the carbonated concrete blocks was affected by two factors: accelerated cement hydration and carbonation extent. A high CO2 concentration, a fast gas flow rate and a moderate relative humidity were essential for enhancing the maturity and the strength development. The developed model based on the maturity approach may accurately predict the strength development of the carbonated concrete blocks.