Bond behavior between FRP sheet and FRP anchor

Document Type : Research Paper

Authors

1 Department of Civil Engineering, Isfahan University of Technology (IUT), Isfahan

2 Department of Civil Engineering, Isfahan University of Technology (IUT)

10.22124/jcr.2023.24067.1616

Abstract

Fiber-reinforced polymer (FRP) anchors are used to prevent or delay the debonding of FRP sheets in the strengthening of structures. There are various methods to prevent or delay the debonding of FRP sheets, among them is the use of FRP anchors. In this research, the behavior of the bond between the FRP sheet and the FRP anchor after the debonding of the reinforcement sheet from the concrete surface was evaluated. Therefore, the specimens were reinforced in such a way that there is no bond between the reinforcement sheet and the concrete surface. The simultaneous increase in the ratio of the cross-sectional area and the length of the fan leads to an increase in the bond strength; therefore, the specimens with a fan length of 90 mm experience an average increase of 50% in bond strength. In this case, the failure mode was anchor debonding from the sheet. Results showed that increasing the length of the fan improved the bond strength. Therefore, the specimens with a fan length of 150 mm reached the bond strength to almost the ultimate tensile strength of the FRP composite. The amount of slip, in this case, is on average 2.5 times the specimens with a 60 mm length of fan. According to the failure mode of the specimens, the embedment depth of 50 mm has the ability to fully transfer the stress to the concrete and the anchor has not been pulled out.

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