Computer Model to Predict the Surface Temperature and Time-of-Wetness of Concrete Pavements and Bridge Decks.
Computer Model to Predict the Surface Temperature and
Time-of-Wetness of Concrete Pavements and Bridge Decks.
(2618 K)
Bentz, D. P.
NISTIR 6551; 24 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; Rush
Service (Telephone Orders Only) 800-553-6847;
Website:
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Order number: PB2001-101594
Keywords:
bridges (structures); bridge decks; building technology;
computer models; concretes; heat transfer; pavements;
surface temperature; time of wetness
Abstract:
This report provides documentation and example results
for a computer model developed to predict the surface
temperature and time-of-wetness (and time-of-freezing)
of concrete pavements and bridge decks. The model is
based on a one-dimensional finite difference scheme and
includes heat transfer by conduction, convection, and
radiation. Environmental conditions are varied by using
the typical meteorological year datafiles available from
the National Renewable Energy Laboratory. Based on the
weather data available in these files and the developed
heat transfer model, both the surface temperature and
the time-of-wetness of the concrete are computed for
typical pavement and bridge deck structures. The
time-of-wetness includes both precipitation and
condensation on the concrete surface. These predictions
will be utilized as input into sorptivity-based service
life models for sulfate attack and freeze/thaw
deterioration, which is the main goal of the NIST
research project being funded by the Federal Highway
Administration.
Building and Fire Research Laboratory
National Institute of Standards and Technology
Gaithersburg, MD 20899