Title: Use of Fly Ash, Blast-Furnace Slag and Condensed Silica Fume for Concrete Block Stripped Immediately After Molding

Author(s): Kiyolshi Kohno, Katsunori Horii, and Hiroo Fukushima

Publication: Symposium Paper

Volume: 79

Issue:

Appears on pages(s): 1165-1176

Keywords: age-stre ngth relation; strength; concrete blocks; dynami ash; manufacturing; no-slump blast furnace c modulus of e concrete; silica; slag; compressive lasticity; fly steam curing; texture.

DOI: 10.14359/6745

Date: 5/1/1983

Abstract:
The use of industrial by-products such as fly ash, blast-furnace slag and ferro-silicon condensed silica fume for making concrete block stripped immediately after molding was investigated in order to save natural resources. Zero-slump concretes containing varying by-products were used. Each concrete block having the size of, 150 x150 x540mm,was manufactured by using an instant-stripping mold. After stripping, the blocks were cured in a steam chamber and a water tank of standard manner. Concrete qualitiessuch as compressive strength, dynamic modulus of elasticity, solidity ratio and surface texture were investigated at given ages. The results of these investigations reveal that there is no great difference between the quality of concretes containing small amounts of by-products and that of the plain concrete. The use of blast-furnace slag is more effective for 28- day strength development. The color of concrete using fly ash or slag is white, and the condensed silica fume substitution is advantageous for steam curing. These by-products may have a useful role in concrete block industry.