 |
Privacy Statement/Security Notice | Disclaimer | FOIA NIST is an agency of the U.S. Commerce Department's |
The following are models that are freely available to the general public. These models have come out of the HYPERCON: Prediction and Optimization of Concrete Performance research program and its predecessors. The technical background for most of these models can be found on-line in An Electronic Monograph: Modeling and measuring the structure and properties of cement-based materials.
More information on the educational version of the VCCTL that can be downloaded for free is available here.
For more information, contact:
For more information, contact:
For more information, contact:
For more information, contact:
A prototype program that addresses the service life prediction of steel-reinforced concrete exposed to chloride ions is available at http://concrete.nist.gov/ciks.html.
The system is also described in detail in an article in the December 1996 issue of Concrete International.
For more information, contact:
CEMHYD3D
Computer Program
Version 3.0 of CEMHYD3D (released in June of 2005), a three-dimensional cement hydration and microstructure development modelling package is available from the pub/bfrl/bentz/CEMHYD3D/version30 subdirectory via anonymous ftp at ftp.nist.gov. A pdf version of the user's manual (NISTIR 7232) is available at the same address in the CEMHYD3D/version30/manual subdirectory. The manual is also available online at the Electronic Monograph Appendix I-2.
In March 2010, a new version of the disrealnew.c program entitled disrealnew031010.c was added to the ftp site. It delays self-desiccation from occuring in the microstructure until 50 % of set has been achieved (when set is being evaluated) and also changes induction period dependence from being based on volume of cement to being based on surface area of cement.
Also in 2010, Nicolas Robeyst completed his Ph.D. thesis at the University of Gent in Belgium, modifying the disrealnew.c and burnset.c programs to better deal with fly ash and slag (at least those available in Belgium). These modified codes are available at the web site in a version3n subdirectory.
Image files and particle size distributions for use with the 3-D model are available by clicking here.A list of Ph.D. theses utilizing CEMHYD3D is available here.
For more information, contact:
HCSSMODEL, a three-dimensional concrete microstructure modelling package is available from the pub/bfrl/bentz/HCSSMODEL subdirectory via anonymous ftp at ftp.nist.gov. A postscript version of the user's manual (NISTIR 6265) is available at the same address in the HCSSMODEL/manual subdirectory. The manual is also available online at the Electronic Monograph, Part I, Chapter 6, Sec. (8).
For more information, contact:
Finite element/finite difference programs
The pub/bfrl/garbocz/FDFEMANUAL/ directory contains programs for computing the linear elastic and linear electric properties of digital images in 2-D and 3-D. These digital images can be of random materials, acquired experimentally or generated by models, or of any other kind of material, whether random or not. The programs are all in simple Fortran 77, and read in the "microstructure" file they are using. There are programs for DC and AC electrical conductivity, linear elasticity, and thermal elasticity. Documentation is available on-line at the Electronic Monograph, Part II, Chapter 2. The pub/bfrl/garbocz/FDFEMANUAL/ directory also contains postscipt and pdf versions of this manual. Hard copies (NISTIR 6269) may be requested from
The 4SIGHT computer program was written to facilitate concrete performance prediction under various exposure conditions. An HTML GUI now exists, so users can now go to the 4SIGHT web page to use the program. The web page contains entries for the user to specify concrete properties and the boundary conditions (ionic species in contact with the concrete). 4SIGHT uses the cedar++ C++ object code library to perform a transport and reaction calculation based on user input. Currently, relevant user input includes concrete mixture proportions, cement properties, crack properties, concrete member dimensions
4SIGHT does not currently model degradation. Rather, it models the reactions, and corresponding changes in transport coefficients, that may occur. Documentation on the 4SIGHT program is also available from NTIS (NISTIR-5612, NISTIR-6747). Additional inquiries may be made via the web or e-mail:
CONCLIFE is Windows-based, user-friendly software for estimating the service life of concrete pavements and bridge decks exposed to sulfate attack and freeze-thaw deterioration. The software was developed jointly between researchers at NIST and the Federal Highway Administration (FHWA). CONCLIFE uses three concrete models and user-specified data on concrete properties and external environmental conditions to estimate the time at which the concrete spalls beyond a user-specified limit. Sorptivity of sulfate ions and water are the primary means of degradation; the software uses a laboratory test for measuring concrete sorptivity, annual precipitation, and estimated rates of concrete spalling.
The software is bundled with a User's Manual and a Technical Report describing its use. Further information may be requested by e-mail:
SULFATE2 is user-friendly software for computing the resistance of concrete to sulfate attack. The model was developed by Professor Barzin Mobasher at Arizona State University. It is a continuum model, which means that it solves coupled partial differential equations for transport and reactions subject to known boundary conditions, without resolving microstructural details. The response of the concrete (expansion and cracking) is modeled by continuum damage mechanics.
The software was developed using MathWorks' MATLAB package. It is distributed as a MATLAB file that can be used immediately with MATLAB. For those without MATLAB, the software has been converted to the C programming language and should compile on platforms having a C compiler available. Both the MATLAB version and the C version are bundled in the download, along with installation instructions.
Available downloads:
Further information or help may be requested by e-mail:
This four-day workshop covers the topics of cement hydration modeling, percolation theory, and computation of transport and mechanical properties along with the key experimental techniques that complement and help validate the models. There is no registration fee to attend the workshop. The 22nd in this series will be held July 20-22, 2011 at NIST. Updated information on this workshop may be obtained at this address . Persons interested in participating in an upcoming workshop may contact the workshop coordinator,
The pub/bfrl/bentz/CMML directory at ftp.nist.gov contains computer programs for modelling cement hydration and percolation processes. Software for IBM and Macintosh-compatible PCs is available in the directories educ-mod/ibmcomp and educ-mod/maccomp respectively, both accessible from the CMML subdirectory. Documentation for these models is available at the Electronic Monograph. Courtesy of Technion, Israel Institute of Technology, a Windows XP-based version of the hydration program is available in the directory educ-mod/windowsxp. Many thanks to Prof. Kostantin Kovler for providing the version and to Semion Zhutovsky for doing the actual programming.
These software packages were developed at the National Institute of Standards and Technology by employees of the Federal Government in the course of their official duties. Pursuant to title 17 Section 105 of the United States Code this software is not subject to copyright protection and is in the public domain. These software packages represent experimental systems. NIST assumes no responsibility whatsoever for their use by other parties, and makes no guarantees, expressed or implied, about their quality, reliability, or any other characteristic. We would appreciate acknowledgement if the software packages are used.
These software packages can be redistributed and/or modified freely provided that any derivative works bear some notice that they are derived from these original packages, and any modified versions bear some notice that they have been modified.
|
Privacy Statement/Security Notice | Disclaimer | FOIA NIST is an agency of the U.S. Commerce Department's |
Date created: 06/18/2001
Last updated: 02/27/2012