Accurate Measurement of Vertical Stress Distribution Underneath Sand Columns

Due to the physical constraints and limitations of existing measurement technologies, accurate and continuous distribution of the vertical stress underneath granular material columns has not been determined experimentally. The grid-based tactile load/force sensor, a new stress measurement technology of high accuracy, is adopted in laboratory-scale experiments to capture the stress distribution underneath sand columns. It has been observed evidently that the stress distribution is non-uniform and there exists stress concentration zone at approximately half-way between the center and the circumference of the column. The results are discussed with reference to previous theoretical and experimental work of other researchers.