Hydration-Strength-Workability-Durability of Binary, Ternary, and Quaternary Composite Pastes
Yi Han1, Seokhoon Oh1, Xiao-Yong Wang1,2
1Department of Integrated Energy and Infra System, Kangwon National University, Chuncheon-si 24341, Korea.
Materials (Basel, Switzerland)
|January 11, 2022
Summary
This study explores using limestone powder, metakaolin, and fly ash as supplementary cementitious materials to reduce carbon emissions in cement. The quaternary-blended paste shows improved durability and sustainability, offering a promising eco-friendly alternative.
Area of Science:
- Materials Science
- Civil Engineering
- Environmental Science
Background:
- The cement industry faces significant pressure to reduce carbon emissions.
- Mineral admixtures offer a potential solution for sustainable cement production.
Purpose of the Study:
- To investigate the impact of limestone powder, metakaolin, and fly ash on cement paste properties.
- To evaluate the sustainability and durability of blended cement pastes, particularly quaternary blends.
Main Methods:
- Preparation of binary, ternary, and quaternary cement pastes with varying admixture proportions.
- Assessment of workability, compressive strength, ultrasonic pulse speed, surface resistivity, and heat of hydration.
- Utilized X-ray diffraction (XRD) and attenuated total reflection Fourier infrared spectroscopy (ATR-FTIR) for material analysis.
Main Results:
- Metakaolin addition decreased cement paste workability.
- Supplementary cementitious materials enhanced cement hydration and long-term compressive strength.
- Increased surface resistivity and reduced heat of hydration were observed with admixture incorporation, especially in quaternary blends.
- Higher amounts of supplementary cementitious materials correlated with reduced carbon emissions.
Conclusions:
- Quaternary-blended cement pastes demonstrate superior durability and sustainability.
- The use of these mineral admixtures presents a viable strategy for lowering the carbon footprint of cement.
- Further development of quaternary-blended pastes is recommended for sustainable construction practices.
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