Vibratory Compaction in the Laboratory of Granular Materials in Long Columns
SourceFor a laboratory study of the drainage of long columns of porous media, a maximum density, uniformly distributed throughout the column, was required. Research resulted in the development of a mechanical technique for the packing of drainage columns, as much as 60 in. long, with glass beads and natural sands of various particle sizes. A vibratory packer used to pack these columns, which are 1 to 8 in. in diameter, provided good reproducibility of dry unit weight and porosity between duplicate columns as well as a vertical uniformity of these properties within the same or duplicate columns. To develop the standard method of packing columns, a study was made of the effects of time, amplitude, and surcharge weight on the uniformity and reproducibility of results. The technique was standardized at a packing period of 10 s and a vibratory amplitude of 0.09 cm.