Abstract
Previous studies have well demonstrated that recycled glass (RG) can be incorporated into cementitious materials to replace 100% river sand as fine aggregates. However, this replacement was found to incur adverse effects on the mechanical properties of the cement mortar. In this study, CO 2 curing was employed to ameliorate these drawbacks. The effect of CO 2 curing on both of the mechanical properties and microstructure of the RG incorporated cement mortar was studied by a series of laboratory tests. The results showed that replacement of river sand by 100% RG led to a 37% decrease in compressive strength and a 32% reduction in flexural strength of the mortar samples under conventional curing. Whereas, CO 2 curing of these samples significantly enhanced both the compressive and flexural strength, with a more pronounced improvement on the former. Such improvements were further reflected by a decrease in both the water absorption and porosity, and by an enhancement of the microstructure. This is attributed to the fact that compared with the mortar samples prepared with 100% river sand, those prepared with 100% RG had a more porous structure due to the smooth surface of RG and thus a poor bonding between the RG and the cement paste. However, such a porous structure encouraged CO 2 gas to penetrate and diffuse more easily into the cementitious matrix, resulting in a higher degree of CO 2 curing.
Original language | English |
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Pages (from-to) | 138-150 |
Number of pages | 13 |
Journal | Construction and Building Materials |
Volume | 179 |
DOIs | |
Publication status | Published - 10 Aug 2018 |
Keywords
- CO curing
- Mechanical properties
- Microstructure improvement
- Recycled glass
ASJC Scopus subject areas
- Civil and Structural Engineering
- Building and Construction
- General Materials Science