Abstract

The shape and texture of four specimens of crushed aggregates produced by different commercial crushers were quantitatively investigated using the modified Fourier method described in earlier articles. Specimens were classified according to size (all in the range 4 to 64 mm) and type of crusher. Results show that on average the shape of different specimens of crushed aggregates vary more than their surface texture; hence, shape is the dominant factor contributing to the total roughness that combines both characteristics. Particles crushed by a jaw crusher are much more elongated and rectangular than particles that passed through a cone crusher, impactor, or rod mill. The total roughness and shape factor of crushed particles decrease in the order: jaw crusher, cone, impactor, and rod mill. Data provided by the modified Fourier technique give more precise shape as well as textural data that could lead to better control of the aggregates' characteristics; shape and texture have an important bearing upon performance of concrete.

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