Development of a Mechanized Traveling Pluviator to Prepare Reconstituted Uniform Sand Specimens

摘要

Preparation of uniform and repeatable reconstituted sand specimens of required density is a prerequisite for obtaining reliable results from laboratory tests. An air pluviation technique is widely used to achieve uniform and repeatable sand specimens. Many of the previously developed air pluviation setups were stationary in nature, and these setups have inherent limitations, which do not allow the preparation of large, uniform sand beds. In this study, a mechanized traveling pluviator (MTP) is developed, which has two main features, including a freely movable hopper and rigid tube made up of Plexiglas to observe the sand flow during pluviation. This study aims at understanding the effect of the number of diffuser sieves, deposition intensity (DI), and height fall (HF) on the relative density (RD) and uniformity of sand specimens. The uniformity of a sand bed is verified by conducting cone penetration tests (CPTs) using a miniature cone. Using the developed MTP setup, large uniform sand specimens with a wide range of relative densities (viz, 38%-100%) can be prepared. For the sand used in the present study, the height of the fall and the depositional intensity significantly influence the RD of sand beds, whereas diffuser sieves control the uniformity of sand beds.