Original Paper(Vol.59 No.10 pp.751-756)

Effect of Mixing Time and Mix Proportion on Properties of High Fly-Ash Paste

Mamoru SAKAMOTO, Koji TAKEWAKA and Toshinobu YAMAGUCHI

Abstract:High fly-ash paste, which has been applied to the fish reef or algal reef, has a complicated organizational structure with very small water-powder ratio. However, by the change in the water-powder ratio or mixing time, its properties are expected to be significantly affected. In this study, experimental investigations were carried out to assess the effect of manufacturing conditions in the properties of high fly-ash paste, such as strength, organizational structure and shrinkage of the paste, in the change of the water-powder ratio and mixing time. As a result, the following was obtained; (1) strength and densification of the organization significantly increased with the extension of mixing time, but initial setting time hardly changed, (2) drying shrinkage strain was 2,000`3,000 at 2 weeks, and was settled 4weeks later, and tended to increase slightly with the mixing time, (3) autogenous shrinkage in the paste at young age is little.

Key Words:Fly-ash, Mixing time, Compressive strength, Pore size distribution, Drying shrinkage, Autogenous shrinkage