Abstract This paper describes experimental research on the wall normal stress in a laboratory-scale coal silo. The stresses were measured during discharge by pressure sensors arranged in the wall of the silo. The results show that the wall normal stresses at the upper part of hopper remain fairly constant for about three-fourths of the discharge, and then oscillate violently. The dead zone and the saturation effect of pressure in silo contribute to the smoothness and steadiness of those stresses in the stable stage of discharge. A tentative procedure is proposed to predict the funnel flow pattern of which the lower merge point has some distance from the edge of the outlet. Furthermore, a large fluctuation traveling upward from the outlet was detected during the initial discharge period. The movement of the lower merge point, which changes the flow pattern and stress state zone, is reasonably responsible for the large fluctuation.

中文翻译：

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试验煤仓壁面法向应力特性

摘要 本文描述了实验室规模煤仓壁面正应力的实验研究。应力是在卸料过程中通过布置在筒仓壁上的压力传感器测量的。结果表明，料斗上部的壁法向应力在大约四分之三的卸料时间内保持相当恒定，然后剧烈振荡。死区和筒仓压力的饱和效应有助于在排放稳定阶段这些应力的平滑和稳定。提出了一种试验性程序来预测漏斗流型，其下部汇合点与出口边缘有一定距离。此外，在初始排放期间检测到从出口向上传播的大波动。下合并点的移动，