results appear to be close to one another and it is

A = area of aggregate

unclear at this time whether this is the range one

P = perimeter of aggregate.

can expect between crushed gravel and crushed

stone. Visual examination of the crushed gravel

The roundness index for a perfect circle is 100.

and crushed stone showed that the crushed

However, with image analysis, because of the

gravel mostly had one fractured face with the re-

square pixels matrix, the best that can be obtained

mainder of the body being rounded. The crushed

is 95. As the material becomes angular, the round-

stone had several fractured faces and was defi-

ness index decreases (Fig. 11b).

nitely more angular than the crushed gravel.

The results of the tests conducted on the VAOT