Title: High-Performance Concrete With Fly Ash

Author(s): C. Muller, R. Hardtl and Peter SchieBl

Publication: Symposium Paper

Volume: 171

Issue:

Appears on pages(s): 173-200

Keywords: Alkalinity; blast-furnace slag; fly ash; heat of hydration; high-performance concrete; high-strength concrete; mass concrete; modulus of elasticity; portland cement; silica fume; stress-strain relationships.

DOI: 10.14359/6096

Date: 8/1/1997

Abstract:
Generally, high-performance concretes can be defined as types of concretes that meet one or more performance requirements in a specific way. Usual concretes are concretes with a compressive strength up to 55 Mpa and fly ash contents of around 20 mass.% relative to the total binding components (c + f). In the production of high-strength concretes (compressive strength > 65 Mpa), silica fume has been used usually in order to achieve the expected strengths at low w/c. In the production of mass concretes blast-furnace slag cements with a high percentage of slag are preferred in order to reduce the heat of hydration released by the cement reaction. The objective of the investigations presented in this paper was to produce high-strength and mass concretes with fly ash and to characterize the performance of these concretes. For this purpose, concretes with fly ash contents of 10, 20 and 30 mass.% relative to (c + f) at w/c between 0.33 and 0.43 are investigated. The properties and the performance of these concretes are presented using the parameters compressive strength and their stress-strain behavior. Beyond this, the performance of mass concretes with high fly ash contents is presented by the example of laboratory experiments and field studies at two newly-built power plants in the East German federal states. Concretes with reduced portland cement contents and fly ash contents between 30 and 60 mass.% relative to (c + f) were used in laboratory tests. Fly ash contents of 53 and 42 mass.% relative to (c + f) were used to produce monolithic base slabs with a concrete volume between 17,000 and 22,000 m3 (production in one operation). The performance of these concretes is shown using the parameters compressive strength development, heat of hydration development and their Ca(OH)z-content.