Abstract
In our studies Mikawa. Chikuma and Seto silica sands we served for the samples. The variation of grain distribution of each sand after giving impact force was checked. The impact mechanism of these sands did not agree to the law of Rittinger and Kick, but fairly agreed with the Rosin-Rammler Distribution formula. It was found out obviously that the Mikawa and Chikuma silica sands had shown entirely different impact mechanism at the grain sizes of 48 mesh and 65 mesh respectively.
1) R—R distribution formulas which were taken from the three kinds of silica sands given 10 kg-cm/g energy are as follows :
Range (mesh) R—R Distribution Formula
Seto Silica Sand 20∼200 R=10−0.1x1.3×100
Mikawa Silica Sand {20∼48 R=10−0.2x0.9×100
{48∼200 R=10−0.3x1.7×100
Chikuma Silica Sand {20∼65 R=10-5x0.5×100
{65∼200 R=10−1.8x1.8×100
2) The peculiar phenomenon of the crushing mechanism of silica sand can be proved from its crystal structure through the observation by Nicol microscope. And the reason that a constant value n is possessed in each R—R distribution formula can be explained by the crystal structure.
3) The grain shape of a silica sand does not vary by crushing until it becomes a single crystal, but as the grain crushed further it gradually changes into angular type.
