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

The shape of aggregates, from whatever source, plays a crucial role in determining the properties of the composite material in which they are embedded (e.g., asphaltic or portland cement concrete). To properly characterize this three-dimensional shape, three-dimensional information is needed. The authors show how this kind of information can be acquired via x-ray computed tomography. 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.

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