Fracture of Brittle Solids. III. Experimental Results on the Distribution of Fragment Size in Single Fracture

Abstract

In papers I and II of this series, it was concluded on the basis of theory and a limited number of experimental samples that the over-all differential probability p′ of single fracture, as a function of the mean fragment dimension x, should show the presence of three peaks. These correspond to the effect of internal flaws of facial and volume type, and of surficial flaws. This result is verified experimentally with good statistics from the mean of data for 36 specimens fractured in gelatin by Bergstrom, Sollenberger, and Mitchell. The effect in this over-all distribution of the exoclastic fragments produced by surficial flaws was subtracted out. The resulting endoclastic differential probability p for the 36 specimens, corresponding to the effect of internal flaws only, shows with good statistics the presence of two peaks arising from facial and volume flaws. The result of I that the number of fragments cumulated over fragment volumes down to a lower limit v should vary as $v^{-\frac{2}{3}}$ for small fragment size is confirmed by measurements for specimens that underwent single rather than plural fracture.