Title:
Mean Spacing of Air Voids in Hardened Concrete
Author(s):
Emmanuel K. Attiogbe
Publication:
Materials Journal
Volume:
90
Issue:
2
Appears on pages(s):
174-181
Keywords:
air-entrained concrete; air entrainment; concrete durability; air voids; freeze-thaw durability; geometric probability; mean spacing; spacing factor; stereology; Materials Research
DOI:
10.14359/4016
Date:
3/1/1993
Abstract:
Geometric probability concepts and stereological principles are used to derive an equation for the mean spacing of air voids in hardened concrete. The equation is [bar/s] = 2 (p¦/ A) where [bar/s] is the mean spacing, p is the volume fraction of paste in the concrete, A is the volume fraction of air in the concrete, and is the specific surface of the air voids. Thus, the input parameters for the equation are the same as those obtained from the standard air-void system analysis of hardened concrete. The equation is valid for all values of paste-to-air ratio, p/A. The mean spacing yields a better estimate of the actual spacing of the air voids in hardened concrete than the standard spacing factor.