Title:
The Effect of Material Degradation on Bond Properties of Fiber Reinforced Plastic Reinforcing Bars in Concrete
Author(s):
Lawrence C. Bank, Moshe Puterman, and Amnon Katz
Publication:
Materials Journal
Volume:
95
Issue:
3
Appears on pages(s):
232-243
Keywords:
bond stiffness; bond strength; composite reinforcements; embedded-rod test specimen; environmental conditioning; FRP reinforcements; material degradation; pull-out tests; scanning electron microscopy
DOI:
10.14359/367
Date:
5/1/1998
Abstract:
A research study on the effect of material degradation of fiber reinforced plastic (FRP) reinforcing bars on their bond strength and bond stiffness properties is reported in this paper. A convenient new embedded-rod test (ERT) specimen was developed and used in the study. The ERT specimen is recommended for future environmental degradation studies of FRP bars. The ERT specimen enables microscopic and mechanical tests to be performed on portions of the same FRP bar after it has been subjected to environmental conditioning while it is embedded in concrete. Photographs and scanning electron micrographs were used to investigate the nature of the degradation in the polyester and vinylester resin matrices and the E- glass fibers of smooth and deformed FRP bars. Pull-out tests were used to investigate the bond strength and bond stiffness characteristics of the FRP bars. A descriptive model of the mechanism of the deterioration of the FRP material is proposed to relate the decreases in bond strengths and stiffnesses to the degradation of the materials in the FRP bars.