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Author
Erdogan, S. T. | Quiroga, P. N. | Fowler, D. W. | Saleh, H. A. | Livingston, R. A. | Garboczi, E. J. | Ketcham, P. M. | Hagedorn, J. G. | Satterfield, S. G.
Title
Three-Dimensional Shape Analysis of Coarse Aggregates: New Techniques for and Preliminary Results on Several Different Coarse Aggregates and Reference Rocks.
Coporate
University of Texas, Austin Federal Highway Administration, Mclean, VA National Institute of Standards and Technology, Gaithersburg, MD
Journal
Cement and Concrete Research, Vol. 36, No. 9, 1619-1627, September 2006
Keywords
aggregates | concretes | rheology | mechanical properties | x ray tomography | geometry
Identifiers
image and shape analsysis; sample preparation; Virtual Reality Modeling Language (VRML) image production; arbitrary reference rocks; mathematical analysis; image acquisition and sieve analysis; numerical shape analysis
Abstract
The shape of aggregates used in concrete is an important parameter that helps determine many concrete properties, especially the rheology of fresh concrete and early-age mechanical properties. This paper discusses the sample preparation and image analysis techniques necessary for obtaining an aggregate particle image in 3-D, using X-ray computed tomography, which is then suitable for spherical harmonic analysis. The shapes of three reference rocks are analyzed for uncertainty determination via direct comparison to the geometry of their reconstructed images. A Virtual Reality Modeling Language technique is demonstrated that can give quick and accurate 3-D views of aggregates. Shape data on several different kinds of coarse aggregates are compared and used to illustrate potential mathematical shape analyses made possible by the spherical harmonic information.