Next: Aggregate Effect
Up: Void-Void Proximity
Previous: Nearest Neighbor
The mean free path is the average length of paste between adjacent air voids along a randomly chosen line passing through the air void system. If an ASTM C 457 linear traverse was performed on a paste specimen containing entrained air voids, the mean free path would be equal to the average paste chord length. It is important to note that this distance is neither the longest nor the shortest distance between air voids in an air void system.
An important difference between the mean free path and either the void-void or the paste-void proximity spacings is that the mean free path is simply a number, and not a distribution. The advantage is that a single number can be used to characterize this measure of spacing. The disadvantage is that a single number yields no information about the expected variability in the paste chord lengths.