GFRP 筋的拉伸性能劣化对其与海水海砂混凝土粘结性能的影响

The effect of tensile performance degradation of glass fiber reinforced polymer (GFRP) bars on their bond performance with seawater sea-sand concrete (SSC) was studied. The tensile strength of a series of 10 mm GFRP bars was tested after immersing in simulated SSC pore solution at different temperatures for different durations. The bond performance of these degraded GFRP bars in SSC was conducted using the pull-out test. The failure mode, bond strength and the characteristics of the stress-slip curve were investigated. The test results indicate that the tensile strength of GFRP bars gradually decreases with the SSC pore solution immersion time. Compared with GFRP bars without immersion, the tensile strength of GFRP bars was reduced by 25%, 29% and 48% after 3 months of immersion at 23℃, 40℃ and 60℃, respectively. The bond strength reduces with the increase of the tensile performance degradation of GFRP bars. Compared with GFRP bars without immersion, their bond strength with SSC was reduced by 8%, 19% and 38% after 3 months of immersion at 23℃, 40℃, and 60℃, respectively.