EXPERIMENTAL RESEARCH ON BOND BEHAVIOR BETWEEN GFRP BARS AND STIRRUPS-CONFINED CONCRETE

Abstract

Abstract: Through the results of 120 pullout tests, the influence of different factors (the surface treatment of GFRP bars, the diameter of GFRP bars, concrete strength grade and the confined effect of stirrups) on the bond behavior of GFRP bars is studied and compared with steel bars. Then, the influence of the confined effect of stirrups on the bond failure and bond strength of GFRP bars is analyzed. Finally, the Bertero-Popov-Eligehausen (BPE) and Cosenza-Manfredi-Realfonzo (CMR) models are used to analyze the rising section of bond stress-slip (τ-s) relationship of GFRP bars in stirrup confined concrete. The test results indicate that when the bond failure interface only occurs on the surface of a GFRP bar, the bond strength is not dependent upon the concrete strength. Moreover, the results indicate that in comparison to specimens without stirrups, their stirrup-containing counterparts are more prone to pullout failure with greater ductility and higher bond strength and corresponding slip. The BPE and CMR models are able to investigate the τ-s relationship between GFRP bars and the stirrups-confined concrete with accuracy. With the experimental data, the specific parameters in the models classified by surface characteristics have been suggested.

Key words: GFRP bars, concrete, stirrups-confined concrete, bond behavior, bond stress-slip relationship, composites

CLC Number:

TB332

HU Cheng-chao, GAO Kui, TU Jian-wei, FU Jin-hai. EXPERIMENTAL RESEARCH ON BOND BEHAVIOR BETWEEN GFRP BARS AND STIRRUPS-CONFINED CONCRETE[J]. Composites Science and Engineering, 2020, 0(10): 13-20.

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