Mechanical strength and freeze-thaw resistance of fly ash alkaline-based mortars containing recycled aggregates submitted to accelerated carbonation

摘要

Carbon dioxide sequestration is crucial so targets for limiting global warming can be achieved. As a consequence it is important to study how CO_2 generated by power plants and other facilities can be sequestrated in valuable products. This paper discloses results of an investigation concerning the mechanical performance and freeze-thaw resistance of fly ash/waste glass alkaline-based mortars with two additives and recycled aggregates exposed to accelerated carbon dioxide curing. Mechanical properties as well as water absorption, elastic modulus and drying shrinkage were studied on it. The results show that the mixtures with calcium hydroxide and sodium hydroxide concentration of 8M leads to the highest compressive strength (10 MPa) which is high enough for the production of masonry blocks. The results on freeze-thaw resistance show that mixtures based on. OPC have lower strength loss, than mixtures that are based on calcium hydroxide.