Mechanical Treatment of Fly Ashes: Strength Development and Workability of Mortars Containing Ground Fly Ashes

ABOUT THE INTERNATIONAL CONCRETE ABSTRACTS PORTAL

  • The International Concrete Abstracts Portal is an ACI led collaboration with leading technical organizations from within the international concrete industry and offers the most comprehensive collection of published concrete abstracts.

International Concrete Abstracts Portal

  


Title: Mechanical Treatment of Fly Ashes: Strength Development and Workability of Mortars Containing Ground Fly Ashes

Author(s): J. Monzo, J. Paya, E. Peris-Mora, and M. V. Borrachero

Publication: Special Publication

Volume: 153

Issue:

Appears on pages(s): 339-354

Keywords: compressive strength; flexural strength; flow table tests; fly ash; mortars (material); particle size distribution; specific surface; strength; workability; Materials Research

Date: 6/1/1995

Abstract:
Presents the results of a study of the influence of ground fly ashes on workability and strength of mortars. Fly ash (T0) was obtained from the thermoelectric power plant of Andorra-Teruel (Spain). Samples of (T0) fly ash were ground using a laboratory ball mill for 10, 40, and 60 minutes (T10, T40, and T60). This process crushed spherical or spheroidal fly ash particles so that the morphology of the particles was substantially modified and the fineness notably increased. Mortars were prepared by replacing from 15 to 60 percent of cement by fly ash. Curing time, curing temperature, and fly ash amount influenced the strength of mortars. Curing times longer than seven days showed significant differences among fly ashes, with compressive and flexural strengths decreasing in the order T60 > T40 > T10 > T0. Increasing the curing temperature from 20 to 40 C produces a rise of compressive strength that exceeds control mortars when T60 and T40 fly ashes were used. It is concluded that the use of ground fly ashes improves the strength of mortars compared with strengths obtained with normal fly ash, but high replacement percentages of ground fly ash adversely affect workability.