On the Stress Distribution of Granular Materials Conically Piled on the Ground [Translated]†

Abstract

Two-directional stress cells which can measure the small normal and friction stress of granular materials on a wall were recently developed. With these cells, the stress distributions of granular materials (silica sand and millet grain) piled conically on a plate are measured and compared with the results of theoretical analysis. The results are as follows:1) The maximum normal stress occurs at a distance of a quarter of the outer radius of the cone of the pile, which is about (0.7∼0.8)γH, where γ is the apparent specific gravity, and H denotes the height of cone.2) The normal stress at the center is rather small, about (0.4∼0.6)γH.3) The maximum frictional stress also occurs at the same position as the maximum normal stress.4) Theoretical analysis gives a maximum normal stress of 0.5γKH(√2/K-k-√K)2/(1-kK)2 at a radius of r=H/√k(2/K-k) and a normal stress at the center of γH[1-K2(ƒ- k)(2/K-k-ƒ)/(1-kK)2]. k denotes the friction coefficient, and K denotes the friction coefficient between granular material and the surface of plate. ƒ is given by the formula (40). This agrees well with the experimental result.† This report was originally printed in J. Soc. Powder Technology, Japan, 23(12), 850-856 (1986) in Japanese, before being translated into English by KONA Editorial Committee with the permission of the editorial committee of the Soc. Powder Technology, Japan.