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Estimating the 95th Percentile of the Paste-Void Spacing Distribution in Hardened Cement Paste Containing Air Entrainment.


pdf icon Estimating the 95th Percentile of the Paste-Void Spacing Distribution in Hardened Cement Paste Containing Air Entrainment. (813 K)
Snyder, K. A.

RILEM Workshop on Frost Dmage in Concrete (PRO 25). Proceedings. June 28-30, 1999, Minneapolis, MN, 75-85 pp, 1999.

Keywords:

cements; air entrainment; cement paste; air-void spacing; air-void system; freeze-thaw; spacing equations

Abstract:

The spacing equations of Powers, Philleo, and Pleau and Pigeon are used to estimate the uniform thickness of paste surrounding entrained air voids that is required to encompass 95% of the air-paste system. Spacing equation accuracy is determined by comparison to the numerically exact result of Lu and Torquato. The air void system is approximated by spheres with radii from a lognormal distribution. For the systems studied here, both the Philleo and the Pleau and Pigeon equations are accurate to within approximately 10%. The Powers spacing factor can be used to estimate the same quantity to within a factor of two, and could be made far more accurate by adjusting the result using the variance in the air void radius distribution.