- Author
-
Clifton, J. R.
- Title
- Predicting the Remaining Service Life of Concrete.
- Coporate
- National Institute of Standards and Technology, Gaithersburg, MD
- Sponsor
- Department of Energy, Oak Ridge, TN
- Report
-
NISTIR 4712,
November 1991,
84 p.
- Distribution
- Available from National Technical Information Service
- Keywords
-
concretes
|
accelerated testing
|
alkali-aggregate reactions
|
corrosion
|
modeling
|
nuclear power plants
|
service life
|
sulfate attach
- Abstract
- Nuclear power plants are providing, currently, about 17 percent of the U. S. electricity and many of these plants are approaching their licensed life of 40 years. The U. S. Nuclear Regulatory Commission and the Department of Energy's Oak Ridge National Laboratory are carrying out a program to develop a methodology for assessing the remaining safe-life of the concrete components and structures in nuclear power plants for continued service. The National Institute of Standards and Technology (NIST) is contributing to this program by identifying and analyzing methods for predicting the remaining life of in-service concrete materials. This report examines the basis for predicting the remaining service lives of concrete materials of nuclear power facilities. Methods for predicting the service life of new and in-service concrete materials are analyzed. These methods include 1) estimates based on experience, 2) comparison of performance, 3) accelerated testing, 4) stochastic methods, and 5) mathematical modeling. New approaches for predicting the remaining service lives of concrete materials are proposed and recommendations for their further development given. Degradation processes are discussed based on considerations of their mechanisms, likelihood of occurrence, manifestations, and detection. They include corrosion, sulfate attack, alkali-aggregate reactions, frost attack, leaching, radiation, salt crystallization, and microbiological attack.