Abstract
For determining the aggregate strength, the author proposes a new method, in which the aggregate is reduced to one half in volume and embedded in fine sand (0.1〜0.3mm) one layer after another, instead of being packed alone in test cylinder as in British Standard 812. The condition of aggregate thus produced is supposed to be more analogous to the one in concrete than in B.S. 812. It was found that there was a linear relation between the compressive load and the crushing rate of expanded-shale aggregate when they were plotted on log-scale co-ordinates. The discussion of the test result shows that the revised method has advantage in deciding the individual strength of aggregate, which is different with its size and that the smaller is the particle, the greater is the strength of it.
