ABSTRACT
Dry pluviation, or the ‘raining of sand through air’, is a commonly employed technique used to prepare sand samples in the laboratory to some specified initial state. It is important, however, that the techniques is calibrated so that the density of the samples produced is known accurately and precisely. This paper presents the results of a study in which the characteristics of pluviated samples of Stockton Beach silica sand are determined as a function of deposition rate and free-fall height. The results indicate that relative densities from 30 to 100% are easily achievable using this technique, and information is provided on sand deposition rates required to achieve sample densities within this range, as a function of the size and spacing of the holes in the shutter used to release sand from the pluviation hopper. Data is also provided on the consistency of the achieved densities, and how this varies as a function of the target density. In general, it is found that the higher densities achieved under slower rates of deposition are more repeatable. Previous observations that sand fall heights greater than 0.5 m have no affect on density are confirmed by the results of this study.
