DEVELOPMENT OF AN AIR PLUVIATION METHODOLOGY FOR PREPARING UNIFORM MODEL GROUND USING SAND

Abstract

Laboratory model tests are extensively employed to examine soil behavior and validate numerical analyses. However, the preparation of dense, uniform and reproducible model grounds continues to pose difficulties, particularly when utilizing basic laboratory apparatus with space constraints. Recent studies have established various pluviation techniques utilizing air, water, or vacuum to reconstruct soil models. This paper presents a simple air-pluviation technique for creating dense and highly uniform model ground in laboratory settings with limited overhead space. The procedure entails determining the correlation among drop height, flow rate, and relative density within a small container, subsequently applying these findings to the actual container dimensions to prepare the model ground for experimentation. The system comprises a portable air pluviator equipped with a funnel, flow-control sieves, a fabric hose, and a supporting crane system to produce uniform model ground utilizing Toyoura sand. The developed system-generated model grounds had a coefficient of variation under 5%, indicating excellent uniformity, well within acceptable parameters for laboratory studies. The research indicates that relative density increases nonlinearly, with a progressively diminishing rate, as drop height rises, while flow rate influences relative density linearly. An empirical equation is presented to estimate the relative density as a function of drop height and flow rate for a fine-sand model substrate.