ASTM C 1437, the Standard Test Method for Flow of
Hydraulic-Cement Mortar, determines how much a mortar
sample fl ows when it is unconfi ned and consolidated.
Mortar is placed inside 2-in. tall conical brass mold. When
the mold is removed, the mortar is vibrated at 1.67 Hz as
the fl ow table rises and drops ½ in., 25 times in 15 seconds.
The mortar changes from a conical shape with a 4-in. base
to a “pancake.” Mortar fl ow is reported as a percentage
based on the change in diameter from 4 in. to the fi nal
diameter of the mortar “pancake.