- Author
-
Carino, N. J.
|
Meeks, K. W.
- Title
- Curing of High-Performance Concrete: Phase 1 Study.
- Coporate
- National Institute of Standards and Technology, Gaithersburg, MD
Tri-State Univ., IN
- Report
-
NISTIR 6505,
April 2001,
39 p.
- Distribution
- 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: http://www.ntis.gov
- Keywords
-
concretes
|
curing
|
high performance concrete
|
mortar
|
statistical analysis
|
tensile strength
- Abstract
- This report summarizes the results of an exploratory study on the effects of curing duration on the variation of mortar strength with distance from the drying surface. A novel, notched cylindrical test specimen was adopted for measuring tensile strength at different depths. Two mortar mixtures with w/c of 0.30 and 0.45 were used; the former was assumed to be representative of the paste system in a high-performance concrete. Specimens were moist cured for (1, 3, or 7) d and then exposed to air at 25 deg C and 50% or 70% RH. The cylinders were sealed to simulate one-dimensional drying in a large member. Tensile strengths were measured at 28 d. Relationships between tensile strength and depth were compared with those of specimens continuously moist cured. The data tended to show that 1 d of moist curing might be sufficient to ensure adequate strength development at a depth of 25 mm from the exposed surface. The phenomenon of increasing strength with drying may have confounded the results, and recommendations for additional studies are provided.