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Strength and Microstructure of Geopolymer Based on Fly Ash and Metakaolin
Salim Barbhuiya1, Edmund Pang2
1Department of Engineering and Construction, University of East London, London E16 2RD, UK.
Materials (Basel, Switzerland)
|May 28, 2022
Summary
This study explores geopolymer concrete as a sustainable alternative to Portland cement, evaluating its strength and microstructure. Geopolymer concrete shows promise for reducing CO2 emissions in the construction industry.
Area of Science:
- Materials Science
- Civil Engineering
- Environmental Science
Background:
- Portland cement production is a significant source of global CO2 emissions (6-7%).
- There is a growing need for sustainable alternatives to traditional cement in concrete production.
- Geopolymers offer potential benefits including high early strength, low permeability, and chemical resistance.
Purpose of the Study:
- To investigate the compressive strength and microstructure of geopolymer concrete.
- To evaluate geopolymer binders utilizing fly ash and a blend of metakaolin and fly ash.
Main Methods:
- Preparation of geopolymer concrete mixes using fly ash and metakaolin-fly ash blends.
- Measurement of compressive strength at 7, 14, and 28 days.
- Microstructural analysis using Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD).
Main Results:
- Geopolymer concrete formulations were successfully prepared and tested.
- Compressive strength development was monitored over 28 days.
- Microstructural characteristics were analyzed to understand material properties.
Conclusions:
- Geopolymer concrete presents a viable, eco-friendly alternative to Portland cement.
- The study provides insights into the mechanical and microstructural properties of fly ash and metakaolin-based geopolymers.
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