Abstract:

The relationship of the minimum values of silo bottom pressures’ changing with the different quantities of filled grain mass and the silo diameters for two different grain sizes was studied. It was found that the data could be well fitted with the Janssen formula. However, the ratio between horizontal and vertical stresses was about 2, much bigger than the ratio 0.4 estimated with the Jaky formula in the Norm of silo engineering, which implied that the stresses of these minimum pressure silos were close to the Rankine passive state. The results showed that although the stress states of the silos was different, they obey well the assumptions given by Janssen.

Key words: granular matter; stress; silo; Janssen model