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Fresh Concrete Rheology - Recent Developments .


pdf icon Fresh Concrete Rheology - Recent Developments . (1441 K)
Ferraris, C. F.; deLarrard, F.; Martys, N. S.

Materials Science of Concrete VI. Proceedings. American Ceramic Society. December 2001, American Ceramic Society, Westerville, OH, Mindess, S.; Skalny, J., Editor(s)(s), 215-241 pp, 2001.

Keywords:

concretes; rheology

Abstract:

The design of concrete with specified properties for an application is not a new science, but it has taken on a new meaning with the wide use of high performance concretes (HPC). The following properties are related to fresh concrete: "ease of placement" and "compaction without segregation." The term, ease of placement, covers various other properties of fresh concrete that are called: workability, flowabilitly, compactibility, stability, finishability, pumpability, and/or consistency. These words are often used interchangeably without a definition based on fundamental measurements of properties. Several attempts were made to better relate fresh concrete properties with measurable quatities. Some researchers treated fresh concrete as a fluid and used the fluid rheology methods to describe concrete flow. This approach, the most fundamental ine, is reviewed in this paper. The main topics addressed are: Review the fundamental definitions of quantities used to uniquely describe the flow of concrete. An overview of the tests that are commonly used to measure the rheology of fresh concrete. Methods to predict the flow of concrete from either compositon or laboratory tests. The main parameters that affect the flow of fresh concrete, such as composition, placement and mixing methods. Two special applications of rheology: pumpable concrete and self-compacting concrete.