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Finite Element and Finite Difference Programs for Computing the Linear Electric and Elastic Properties of Digital Images of Random Materials

Published

Author(s)

Edward J. Garboczi

Abstract

This manual has been prepared to show some of the theory behind, and the practical details for using, various finite element and finite difference computer programs that have been developed for computing the effective linear properties of random materials whose microstructure has been stored in a 2-D or 3-D digital image. Thirteen different computer programs are described, including finite element conductivity and elastic programs, finite difference programs for dc and ac conductivity, finite element elastic programs that include thermal strains (eigenstrains), and three auxiliary programs for Gaussian quadrature and phase percolation. All the programs are written in FORTRAN 77, and operate on an arbitrary digital image that is read from a file. Arbitrary symmetric conductivity tensors and arbitrary elastic moduli tensors can be used in the finite element programs. In the finite difference programs, the conductivity tensors must be diagonal. Only linear elastic and linear conductivity problems are considered. The programs can of course be extended to other problems that have a similar mathematical basis.
Citation
NIST Interagency/Internal Report (NISTIR) - 6269
Report Number
6269

Keywords

building technology, computer modelling, concrete, eigenstrain, elastic moduli, electrical conductivity, finite difference, finite element, linear properties

Citation

Garboczi, E. (1998), Finite Element and Finite Difference Programs for Computing the Linear Electric and Elastic Properties of Digital Images of Random Materials, NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=860168 (Accessed March 4, 2024)
Created December 1, 1998, Updated February 19, 2017