Title:
Advantages of Prepreg FRP Systems for Extending Service Life of Concrete Members in Wet Environments
Author(s):
Erblina Vokshi
Publication:
Symposium Paper
Volume:
327
Issue:
Appears on pages(s):
1.1-1.10
Keywords:
under-water repairs, underwater CFRP, pile strengthening, confinement, under-water cure, corrosion, bond durability
DOI:
10.14359/51713321
Date:
11/1/2018
Abstract:
SYNOPSIS: The use of wet lay-up fiber-reinforced polymers (FRPs) in the construction industry continues to grow. Their lightweight, durability, and good material properties makes them very desirable in the concrete repair industry. Research has shown that these products greatly improve the strength of repaired corroded members and reduce the rate of post-repair corrosion. There is a lack of research, however, in understanding how curing of these systems in the presence of moisture or underwater may affect their ability to strengthen and protect reinforced concrete. In this paper, data on material properties of a prepreg system, cured in laboratory conditions and under-water is presented and compared. The results show that there is a very small drop in tensile material properties when the system is cured underwater. Compression of concrete cylinders strengthened with one layer of the system and cured underwater is shown to be in agreement with ACI 440.2R-08’s confinement equations. Durability testing of the bond between the system and reinforced concrete using dolly pull-off test shows a 90% bond strength retention after 1,000hr exposure to various aggressive environments.
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