Effect of Class C and Class F Fly Ash on Early-Age and Mature-Age Properties of Calcium Sulfoaluminate Cement Paste

Sukanta K. Mondal, Carrie Clinton, Hongyan Ma, Aditya Kumar and Monday U. Okoronkwo ()
Additional contact information
Sukanta K. Mondal: Sustainable Materials Laboratory (SusMatLab), Missouri University of Science and Technology, Rolla, MO 65409, USA
Carrie Clinton: Sustainable Materials Laboratory (SusMatLab), Missouri University of Science and Technology, Rolla, MO 65409, USA
Hongyan Ma: Department of Civil, Architectural and Environmental Engineering, Missouri University of Science and Technology, Rolla, MO 65409, USA
Aditya Kumar: Department of Materials Science and Engineering, Missouri University of Science and Technology, Rolla, MO 65409, USA
Monday U. Okoronkwo: Sustainable Materials Laboratory (SusMatLab), Missouri University of Science and Technology, Rolla, MO 65409, USA

Sustainability, 2023, vol. 15, issue 3, 1-18

Abstract: To promote the sustainable development of eco-efficient calcium sulfoaluminate (CSA) cements through the partial replacement of the CSA clinker with supplementary cementitious waste products, the effects of coal fly ashes on the early-age and mature-age properties of a calcium sulfoaluminate (CSA)-based cement paste were investigated. The impacts of both Class C and Class F fly ashes on the rheological properties, hydration kinetics, and compressive strength development of CSA cement paste were studied. Rheology-based workability parameters, representing the rate of loss of flowability, the rate of hardening, and the placement limit, were characterized for the pastes prepared with fixed water-to-cement (w/c) and fixed water-to-binder (w/b) ratios. The results indicate a slight improvement in the workability of the CSA paste by fly ash addition at a fixed w/b ratio. The isothermal calorimetry studies show a higher heat of hydration for the Class C fly ash-modified systems compared to the Class F-modified systems. The results show that fly ash accelerates the hydration of the calcium sulfoaluminate cement pastes, chiefly due to the filler effects, rather than the pozzolanic effects. In general, ettringite is stabilized more by the addition of Class F fly ash than Class C fly ash. Both fly ashes reduced the 1-day compressive strength, but increased the 28-day strength of the CSA cement paste; meanwhile, the Class C modified pastes show a higher strength than Class F, which is attributed to the higher degree of reaction and potentially more cohesive binding C-S-H-based gels formed in the Class C fly ash modified systems. The results provide insights that support that fly ash can be employed to improve the performance of calcium sulfoaluminate cement pastes, while also enhancing cost effectiveness and sustainability.

Keywords: sulfoaluminate cement; fly ash; hydration; rheology; eco-efficient cement; sustainability of cements (search for similar items in EconPapers)
JEL-codes: O13 Q Q0 Q2 Q3 Q5 Q56 (search for similar items in EconPapers)
Date: 2023
References: View complete reference list from CitEc
Citations: View citations in EconPapers (1)

Downloads: (external link)
https://www.mdpi.com/2071-1050/15/3/2501/pdf (application/pdf)
https://www.mdpi.com/2071-1050/15/3/2501/ (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:gam:jsusta:v:15:y:2023:i:3:p:2501-:d:1051767

Access Statistics for this article

Sustainability is currently edited by Ms. Alexandra Wu

More articles in Sustainability from MDPI
Bibliographic data for series maintained by MDPI Indexing Manager ().