Title: Partially Compacted Weight of Concrete as a Measure of Workablity

Author(s): Bryant Mather

Publication: Journal Proceedings

Volume: 63

Issue: 4

Appears on pages(s): 441-450

Keywords: angle of repose;compaction;concrete;consistancy;fresh concrete;mass concrete;research;slump;unit weight;workablity.

DOI: 10.14359/7632

Date: 4/1/1966

Abstract:
A study of the compacting-factor method of measuring workability of small-aggregate concrete (1 YZ in.) indicated that: (a) the degree to which concrete heaps when a mold is allowed to overfill from the discharge of a mixer reaches a maximum at an intermediate workability and decreases as the mixture gets either drier or wetter; and (b) the net, loose weight of concrete in a mold after strike off increases with increasing workability. The net, loose weight of concrete in a mold filled to overflowing and then struck off could form the basis for controlling workability of mixtures having a slump not greater than 3 in. Studies using mixtures with 6-in. aggregate indicated that heaping weight, struck-off weight, and compacting factor increase with increased water content until the slump reaches from 1 YZ to 3 in. and then they decrease. Routine determinations of heaping weight or struck-off loose weight might be used to detect batches of excessive or deficient water content which could be rejected before delivery to the forms.