Title:
Five-Year Exposure Test on Long-Term Properties of Concretes Containing Fly Ash, Blast-Furnace Slag, and Silica Fume
Author(s):
T. SasataniI, K. TorllI, and M. Kawamura
Publication:
Symposium Paper
Volume:
153
Issue:
Appears on pages(s):
283-296
Keywords:
blast furnace slag; carbonation; chlorides; compressive strength; environments; exposure; fly ash; penetration tests; silica fume; tests; velocity; Materials Research
DOI:
10.14359/1075
Date:
6/1/1995
Abstract:
Presents results of five-year exposure tests on the long term properties of concretes containing fly ash (FA), blast furnace slag (BFS), and silica fume (SF). Four kinds of concretes with and without a mineral admixture (OPC concrete, FA 30 percent concrete, BFS 50 percent concrete, and SF 10 percent concrete) were prepared. After 28 days of initial curing, they were exposed to different environments for five years. Compressive strength, pulse velocity, depth of carbonation, and chloride ion penetration of concrete were determined at various intervals of exposure time. From the results, it was found that under the indoor exposure condition, influences of initial curing conditions on the long term strength development of concrete were especially pronounced for FA 30 percent concrete and BFS 50 percent concrete, but that under the outdoor exposure conditions, its influence was considerably reduced due to the supply of rainfall during the outdoor exposure. On the other hand, SF 10 percent concretes showed some reduction in compressive strength when they were initially cured in water for seven days and then continuously air-dried indoors for a long period. The depth of carbonation of BFS 50 percent concrete and FA 30 percent concrete was much greater than that of the corresponding OPC concrete and SF 10 percent concrete when they were exposed indoors or outdoors for five years. Furthermore, all mineral admixtures used in this study were found to be equally efficient in preventing chloride ions from intruding into concretes under a marine environment.