Investigation of Partially Compacted Weight of Concrete as a Measure of Workability. Report 1. Preliminary Tests

摘要

Apparatus for performing the compacting-factor test as described in British Standard 1881:1952 was constructed, and two series of tests were made to determine the degree to which variation in partially compacted weight of concrete specimens can be used as a measure of workability. In the first series of tests a number of batches of each of two concrete mixtures having 1-1/2- and 2-1/2-in. slumps, respectively, were tested. In the second series the water content of a nominal 2-in.-slump mixture was varied to give seven mixtures with slumps ranging from 0 to 8 in. It is concluded that the net, struck, partially compacted weight of concrete in a suitable mold, filled by discharge to overflowing in a standard manner, could form the basis of control of workability in the laboratory or in the field, provided the concrete has a slump that does not normally exceed 3 in. (Author)