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Acquiring, Analyzing, and Using Complete Three-Dimensional Aggregate Shape Information.


pdf icon Acquiring, Analyzing, and Using Complete Three-Dimensional Aggregate Shape Information. (460 K)
Garboczi, E. J.; Martys, N. S.; Saleh, H. H.; Livingston, R. A.

AGGREGATES, Concrete, Bases, and Fines, 9th Annual Symposium. Proceedings. Center for Aggregates Research. April 22-25, 2001, Austin, TX, 1-13 pp, 2001.

Keywords:

aggregates; rheology; x ray computed tomography; spherical harmonic; shape; suspensions; concretes

Abstract:

The shape of aggregates, from whatever source, plays a crucial role in determining the properties of the composite material in which they are embedded, for example asphaltic concrete or portland cement concrete. To properly characterize this three-dimensional shape, three-dimensional information is needed. We show how this kind of information can be acquired via x-ray computed tomography (CT). Mathematical "burning" algorithms can be applied to a multi-aggregate image to extract individual particles of various sizes. A spherical harmonic mathematical analysis can then be used to completely characterize the three-dimensional shape of each extracted aggregate. This real shape information can then be incorporated into algorithms for simulating the rheology of suspensions (fresh concrete or other materials) and into algorithms for simulating the structure of portland cement concrete.