Research petrographic, Virginia Highway and Transportation Research Council, Charlottesville, VA
The spacing factor for the proportional number of small air voids ¯Lps as proposed by Walker in 1980 and the air-void parameters normally obtained by ASTM Practice for Microscopical Determination of Air-Void Content and Parameters of the Air-Void System in Hardened Concrete (C 457) were each correlated with the durability factor and weight loss found by ASTM Test for Resistance of Concrete to Rapid Freezing and Thawing (C 666) Procedure A for 151 concretes. The correlation coefficients were examined, and it was found that for the durability factor the classical spacing factor from ASTM C 457 gave a slightly but not significantly better correlation than did ¯Lps. The 151 concretes were divided into three groups according to their source. In no case did the correlation obtained from ¯Lps significantly exceed the spacing factor calculated from ASTM C 457.
Paper ID: CCA10355J