journal article·2018-09Open access

Properties of quicklime(CaO)-activated Class F fly ash with the use of CaCl2

Dongho Jeon, Woo Sung Yum, Yeonung Jeong, Jae Eun Oh

Abstract

Abstract This study reports the significant effect of CaCl2 on strength improvement in CaO-activated Class F fly ash system. In these systems, the presence of CaCl2 promotes (1) a higher degree of fly ash dissolution, (2) increasing C-S-H formation, and (3) an overall reduction of pore size and volume, resulting in increased strength. However, while more C-S-H, which is responsible for strength increase, was produced with higher CaCl2 content, extreme doses of CaCl2 resulted in strength degradation; more importantly, the best quantity of CaCl2 for the greatest strength was dependent on the water-to-binder weight ratio (w/b). This dependency was closely related to the formation of calcium oxychloride, which generally causes severe expansive cracking and depends on w/b.
Source: openaire · Quality: candidate unverified · Source record ↗

Research context

OpenAlex topics: Concrete and Cement Materials Research · Recycling and utilization of industrial and municipal waste in materials production · Magnesium Oxide Properties and Applications

SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.

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