Hard Core/Soft Shell Microstructural Model for Studying Percolation and Transport in Three-Dimensional Composite Media.
Hard Core/Soft Shell Microstructural Model for Studying
Percolation and Transport in Three-Dimensional Composite
Bentz, D. P.; Garboczi, E. J.; Snyder, K. A.
NISTIR 6265; 55 p. January 1999.
Available from: National Technical Information Service
(NTIS), Technology Administration, U.S. Department of
Commerce, Springfield, VA 22161.
1-800-553-6847 or 703-605-6000;
Order number: PB99-114647
building technology; computer models; concretes;
diffusivity; microstructure; percolation; simulation
This user's manual provides documentation and computer
program listings for the three-dimensional hard
core/soft shell microstructure model developed at the
National Institute of Standards and Technology. The
model has been developed to represent the three phase
microstructure of a concrete composite consisting of a
bulk matrix (cement paste), hard core particles located
at random in the bulk (aggregates), and a concentric
soft shell surrounding each hard core particle
(interfacial transition zone paste). However, this
microstructural model is generic in nature and has also
been applied to modelling air voids in concrete,
macro-defect-free cements, and silica sol gels. Any
system consisting of partially overlapping or totally
non-overlapping spherical particles can be modelled
using the developed computer programs, perhaps with some
minor modifications. In addition to generating a
representative 3-D microstructure, the programs can also
be used to assess the percolation characteristics of the
microstructure and estimate a diffusivity (or electrical
or thermal conductivity) for the composite media.
Complete program listings and example datafiles are
provided in the appendices of this documentation and the
software is also available for downloading via anonymous
ftp. The computer codes are available via anonymous ftp
as part of the Computer Integrated Knowledge System for
High-Performance Concrete being developed as part of the
Partnership for High Performance Concrete Technology
program in the Building and Fire Research Laboratory at
the NIST. They may be accessed in the
/ftp/pub/HCSSMODEL sub-directory from edsel.cbt.nist.gov
(220.127.116.11) by loggin in as user "anonymous" and
providing your e-mail address as the password.
Postscript and pdf versions of this manual are also
available in a subdirectors, /ftp/pub/HCSSMODEL/manual.