Analysis of CCRL Proficiency Cements 135 and 136 Using CEMHYD3D.
Analysis of CCRL Proficiency Cements 135 and 136 Using
CEMHYD3D.
(6063 K)
Bentz, D. P.; Feng, X.; Haecker, C. J.; Stutzman, P. E.
NISTIR 6545; 23 p. August 2000.
Available from:
National Technical Information Service
(NTIS), Technology Administration, U.S. Department of
Commerce, Springfield, VA 22161.
Telephone:
1-800-553-6847 or 703-605-6000;
Fax: 703-605-6900.
Website: http://www.ntis.gov
Order number: PB2001-100126
Keywords:
cements; computer models; heat of hydration; hydration
kinetics; particle size distribution; SEM imaging;
strength development
Abstract:
This NISTIR provides experimental and computer modeling
results for cements 135 and 136 issued by the Cement and
Concrete Reference Laboratory at NIST in January of
2000. The purposes of this report are to characterize
these cements via scanning electron microscopy (SEM)
analysis and to document the ability of the NIST
computer model, CEMHYD3D, to predict the hydration
kinetics, heat of hydration, and mortar strength
development of Portland cements evaluated in the CCRL
proficiency sample program. The general procedure to
evaluate a new cement is as follows: 1) two-dimensional
SEM backscattered electron and X-ray microanalysis
images of the cement of interest are obtained, along
with a measured particle size distribution (PSD), 2)
based on analysis of these images and the measured PSD,
three-dimensional microstructures of various
water-to-cement ratios are created and hydrated using
CEMHYD3D, and 3) the model predictions for degree of
hydration under saturated and sealed conditions, heat of
hydration (ASTM C186), and strength development of
mortar cubes (ASTM C1O9) are compared to experimental
measurements either performed at NIST or at the
participating CCRL proficiency sample evaluation
laboratories. For both cements, generally good agreement
is observed between the model predictions and the
experimental data, demonstrating the predictive
capabilities of CEMHYD3D.
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National Institute of Standards and Technology
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