Studies on Pozzolanic Materials as Portrand Cement Admixture, (III)

Abstract

On continuing the previous studies (This Journal, 62 [696] 403-406 (1954); 63 [714] 523-527 (1955)), the authors report in the present paper the results of further studies on various properties of fly ash by comparing with other siliceous pozzolanic admixtures used in the previous reports (loc. cit.). The collected samples were three kinds of fly ash from electric power plants (Chicago fly ash from America, Ube fly ash from the Ube Kosan Co., and KFA fly ash from the Kansai Denryoku Co.), one coal ash KPA quenched in water pond from the Kansai Denryoku Co., and two kinds of natural siliceous pozzolanic materials (Beppu-hakudo and Oya-ishi used in the previous reports (I) and (II)). These samples were analysed and compared by the common total and special soluble analysis. The testing of lime-adsorption and the electron microscopic photographs gave clear difference between fly ash and natural siliceous pozzolanic materials. The test of swelling in distilled water or in lime water, the alkalinity test, the bending and compressive strength tests by the standard 1:2-cement sand mortar, and the bleeding test (ASTM Proc., 49, 891 (1949)), etc., gave clear aids for the discrimination between true fly ash, pond ash and other siliceous admixtures.