Title: Scaling Tests of Silica Fume Concrete and the Critical Spacing Factor Concept

Author(s): Michel Pigeon, Daniel Perraton, and Richard Pleau

Publication: Symposium Paper

Volume: 100

Issue:

Appears on pages(s): 1155-1182

Keywords: air-entrained concretes; concrete durability; curing; deicers; freeze-thaw durability; scaling; silica; tests; Materials Research

DOI: 10.14359/2070

Date: 4/1/1987

Abstract:
ASTM C 672 scaling tests were carried out on concretes containing 0, 5, and 10 percent silica fume, and with air-void spacing factors in the 100 to 200 æm range. Two methods of curing were compared: 7 days in water and the use of a curing compound. Water containing 2.5 percent sodium chloride was used for the scaling tests, as well as pure water. Results indicate that, although scaling tends to increase with the silica fume content, silica fume concrete can have a fair scaling resistance, and also that specimens cured in water, regardless of the silica fume content, have a lower resistance to scaling than specimens cured with a membrane. Considering previously published data by two of the authors, results further show that the critical air-void spacing factors obtained from ASTM C 666 (Procedure A) freeze-thaw cycle tests are not applicable to scaling. Spacing factors required for good scaling resistance are generally lower than those required for freeze-thaw cycle durability, and total protection against scaling does not seem possible. A short review of the literature confirms that critical spacing factors are usually higher than 200 æm.