Studies on some factors affecting CO2 curing of lightweight concrete products

Abstract This paper deals with the effects of several factors, such as CO 2 pressure, curing time, water-to-cement ratio and continued curing after CO 2 curing on temperature profiles, CO 2 curing degree and strength of concrete. Results indicated that the accelerated reactions between CO 2 and cement minerals happen mainly during the first 15 min regardless of CO 2 pressure and pre-conditioning environment. CO 2 curing degree and strength increased as the CO 2 pressure and curing time increased. The concrete specimens should have a water-to-cement ratio greater than certain value so as to facilitate the moulding of concrete products and to achieve a high CO 2 curing degree. CO 2 cured specimens will continue to gain strength due to the hydration of cement minerals unreacted during the CO 2 curing if the specimens are kept in moist environment.