The strength of concrete at early ages has assumed a co~iderable significance in recent years due to the several specific requirements ot the modern construction industry, like the early striking or forms, early transfer of prestress etc. However, fly ash concretes are known to-have a lower early ag
Effectiveness of fly ash for strength and durability of concrete
β Scribed by D.W.S. Ho; R.K. Lewis
- Publisher
- Elsevier Science
- Year
- 1985
- Tongue
- English
- Weight
- 413 KB
- Volume
- 15
- Category
- Article
- ISSN
- 0008-8846
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β¦ Synopsis
The effectiveness, K, of a fly ash can be defined as the ratio of the amount of cement replaced to the amount of fly ash added, provided the specified requirements of the concrete are maintained. It is generally assumed that the effectiveness of a fly ash can be treated as a constant. This paper presents results on concrete made with various mix proportions using three different cements and fly ash from three different sources. It was found that the K factor of each fly ash in achieving common 28-day compressive strength varies over a wide range depending on the amount of fly ash used, the type of cement, the incorporation of chemical admixtures and the particular strength level chosen. Besides strength, K can also be calculated for other properties. For the materials used in this investigation, the K factors with respect to carbonation were found to be unequal to K factors for strength.
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