To study the mechanism of the influence of axial compression ratio on the seismic performance of GFRP-reinforced concrete(GFRP-RC)beam-column joints,pull-out tests were conducted to investigate the bond between GFRP bars and concrete under various lateral pressure,and the corresponding bond-slip constitutive model was established.Through quasi-static tests and numerical simulation analyses of the joints,the failure modes and bearing capacity of GFRP-RC joints under different axial compression ratios were studied.The results show that the bond strength between GFRP bars and concrete increases approximately linearly with the lateral compressive stress.In the numerical simulation,the proposed bond-slip model accounting for the lateral pressure in the joint domain can more accurately reflect the bearing characteristics of GFRP-RC joints under different axial compression ratios.When the axial compression ratio is within the range of 0.15-0.35,the bearing capacity of the joint increases by about 7％with an increase of 0.1 in axial compression ratio.By restraining the bond-slip of reinforcement and cracks of concrete in the joint domain,the stiffness,ductility,and energy dissipation capacity of the joint specimens are improved,which is conducive to forming the"stronger joint"mechanism.
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