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Discussion of "The Use of the Flow Length Concept to Assess the Efficiency of Air Entrainment With Regards to Frost Durability: Part 1. Description of the Test Method" by R. Pleau and M. Pigeon.


pdf icon Discussion of "The Use of the Flow Length Concept to Assess the Efficiency of Air Entrainment With Regards to Frost Durability: Part 1. Description of the Test Method" by R. Pleau and M. Pigeon. (381 K)
Snyder, K. A.

Cement, Concrete, and Aggregates, Vol. 19, No. 2, 116-119, December 1997.

Keywords:

air entrainment; frost durability; flow length concept; building technology; concretes; air-void system; air-void spacing

Abstract:

In an approach similar to that of Philleo, the authors have attempted to calculate the distribution of distances between random points in the paste and the nearest air void surface (paste-void proximity distribution). This approach has a distinct advantage over single parameter spacing equations that cannot characterize a distribution of spacings. However, like the Philleo equation, the authors' equation for the paste-void proximity distribution is an approximation, and is only exact for zero air content. This dicussion will demonstrate this point calculsively for monodispersed spheres. Additionally, by comparing results of a similar numerical experiment published previously to predictions based upon the authors'equation, it can be demonstrated that the authros' equation contains considerable error at concrete air content of 5% for a zeroth-order logarithmic distribution of sphere diameters.