Affiliation:
1. Área de Ingeniería de la Construcción, Escuela Politécnica Superior de Belmez, Universidad de Córdoba, 14240 Córdoba, Spain
2. Área de Química Inorgánica, Escuela Politécnica Superior de Belmez, Universidad de Córdoba, 14240 Córdoba, Spain
Abstract
The objective of the present study was to explore three types of vibro-compacted precast concrete mixtures replacing fine and coarse gravel with a recycled/mixed concrete aggregate (RCA or MCA). The portlandite phase found in RCA and MCA by XRD is a “potential” CO2 sink. CO2 curing improved the compressive strength in all the mixtures studied. One tonne of the mixtures studied could be decarbonised after only 7 days of curing 13,604, 36,077 and 24,635 m3 of air using natural aggregates, RCA or MCA, respectively. The compressive strength obtained, XRD, TGA/DTA and carbon emission evaluation showed that curing longer than 7 days in CO2 was pointless. The total CO2 emissions by a mixture using CO2 curing at 7 days were 221.26, 204.38 and 210.05 kg CO2 eq/m3 air using natural aggregates, RCA or MCA, respectively. The findings of this study provide a valuable contribution to carbon emission evaluation of CO2 curing in vibro-compacted precast concrete with recycled/mixed concrete aggregates (RCA or MCA). The technology proposed in this research facilitates carbon capture and use and guarantees enhanced compressive strength of the concrete samples.
Funder
Consejería de Transformación Económica, Industria, Conocimiento y Universidades. Junta de Andalucía. PREFABRICO-II Research Project
Andalusian FEDER Operational Program
Subject
General Materials Science