Title:
Effects of Freeze-Thaw Exposure on Performance of Concrete Columns Strengthened with Advanced Composites
Author(s):
H. A. Toutanji, and P. Balaguru
Publication:
Materials Journal
Volume:
96
Issue:
5
Appears on pages(s):
605-611
Keywords:
carbon; compressive strength; concretes; damage; durability; fibers; glass; plastics, polymers, and resins
DOI:
10.14359/664
Date:
9/1/1999
Abstract:
This paper presents the results of an experimental study on the performance of concrete columns wrapped with carbon and glass fiber reinforced polymer (FRP) composite sheets subjected to freeze-thaw conditions. The wrapped concrete specimens were conditioned in two different environments: room temperature (23 C) and 300 freeze-thaw cycles. The stress-strain behavior in compression of the freeze-thaw exposed specimens was obtained to evaluate their strength, stiffness, and ductility, which were then compared to the performance of unconditioned samples (room temperature). Two sets of tests were conducted using the exposed specimens. In the first set of tests, in which the entire length of the samples was subjected to compression, failure occurred at the top and bottom. The authors felt that the failure occurred due to the deterioration of concrete which was exposed rather than the failure of the wrapping system. Therefore, the top and bottom (75 mm each) parts were sawed off and the tests were repeated using the shorter specimens. The shorter specimens retained 95 percent of the strength for the carbon composite wraps, and approximately 88 percent of the strength for the glass composite wraps. The experimental results of the three sets of samples consisting of virgin, freeze-thaw exposed, and modified, and analytically predicted results are discussed.