ESTIMATING THE 95 th PERCENTILE OF THE PASTE- VOID SPACING DISTRIBUTION IN HARDENED CEMENT PASTE CONTAINING AIR ENTRAINMENT
نویسنده
چکیده
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.
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