[1297] Mechanisms behind Dimensional and Mass Changes Induced by Accelerated Carbonation of Hardened Cementitious Materials
Keywords:accelerated carbonation、carbonation shrinkage、C-S-H decalcification、GGBS
Dimensional and mass changes induced by accelerated carbonation at 20% CO2 were investigated in pre-conditioned OPC and GGBS blended cement hardened pastes. An abrupt mass increase followed by a slow ongoing mass decrease was observed, and the final mass change was positive for OPC, but negative for the blended pastes, which also exhibited larger shrinkage. The Calcium Carbonate filling effect is counteracted by the C-S-H decalcification shrinkage and the water release upon carbonation, the key mechanisms governing microstructural changes induced by accelerated carbonation.