Title:
Long-Term Strength of High-Strength Silica Fume Concrete
Author(s):
Magne Maage, Sverre Smeplass, and Randulf Johansen
Publication:
Symposium Paper
Volume:
121
Issue:
Appears on pages(s):
399-408
Keywords:
compressive strength; concrete cores; cubes; silica fume; high-strength concretes; long-time study; research; Materials Research
DOI:
10.14359/2552
Date:
11/1/1990
Abstract:
Use of silica fume is important to produce high-strength concrete. Possible negative effects on long-term properties are, therefore, of vital interest for the future development of high-strength concrete. It has been reported that silica fume concrete stored in air showed strength loss from 90 days to 5 years, but courses are not discussed. The report was based on a limited number of results. Similar results are not found in high-strength concrete up to 10 years old either in laboratory tests or testing samples from existing structures in Norway. Results from two major research projects showed that, for laboratory-stored specimens, the strength increased or was constant for concrete stored in water or air, respectively. No difference was found between high- and normal strength concretes. The increase was somewhat higher for concretes without silica fume compared to concretes with up to 20 percent silica fume by weight of cement. Furthermore, the strength increase was somewhat higher for water-stored concretes than for air-stored. However, high-strength silica fume concrete was not more sensitive to early drying than concrete without silica fume. High-strength concrete from several existing structures did not exhibit the same consistent pattern in strength development, however. This is probably due to insufficient documentation at an early age. However, the results did not show any significant negative long-term strength development.