Mixture Design Considerations

Fresh properties and Compressive strength of Ultra high strength mortar using fly ash finely powdered from single micron to submicron region

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Abstract

This research examined the application possibility of fly ash discharged from coal-fired power plant as an admixture for Ultra High Strength Fiber Reinforced Concrete (designated below as UFC). Silica fume is generally used as an admixture in order to enable mixing at very low water to binder ratio in Japan. However, the quality fluctuation of silica fume is large. Therefore, there are problems with the quality variations of fresh properties and strength characteristics of the UFC. In this study, fly ash finely powdered with particle diameter of 0.4 to 2μm in 50% cumulative volume passing diameter was prototyped. This is aimed at expanding the applications of fly ash generated in large quantities in Japan and to increase its added value. Utilizing this prototype fly ash as the admixture, fresh properties and compressive strengths of the mortars were tested. As a result, mortar with fly ash ultrafine powder displayed better fresh and strength performance than when silica fume is used. Based on the above, the possibility of applying fly ash ultrafine powder as an admixture for UFC was discovered.

Keywords: Fly ash ultrafine powder, Admixure, mortar

How to Cite:

Fujiwara, S., Nito, N., Kubota, K. & Fujiwara, H., (2019) “Fresh properties and Compressive strength of Ultra high strength mortar using fly ash finely powdered from single micron to submicron region”, International Interactive Symposium on Ultra-High Performance Concrete 2(1). doi: https://doi.org/10.21838/uhpc.9654