Title:
Review of international specifications for use of fly ash in Portland cement concrete
Author(s):
Oscar E. Manz
Publication:
Symposium Paper
Volume:
79
Issue:
Appears on pages(s):
187-200
Keywords:
concretes; fineness; fly ash; free lime; pozzolans; . lardenlng) ; specificati6E.
DOI:
10.14359/6691
Date:
5/1/1983
Abstract:
There are several federal and state specifications being used in the United States involving the use of fly ash in portalnd cement concrete. The American Society for testing and Materials establichwed a stancdard on fly ash in 1954 and several foreign specifications that followed had similar formats. However, for use by all agencies in that particular country. In recent years there have been a few other proposed unique classification systems. In the United States, the classificaiton of fly ash by reference to the type of coal has been questioned, as well as some of the specification limits. The many new "Western" fly ashes have caused concern for some properties not presently covered, such as free lime and sulfate resistance. Also, due to poor correlation between laboratory pozzolanic activity tests and field performance, there is a need for a system in terms of parameters controlling performance. A review of the various specifications will be presented, and will include a disussion of the similarities as well as items that are unique to a particular specification. An attempt will be made to present a universal specification scheme for fly ashes.