天然海水浸泡对FRP筋抗压性能的影响

Effect of Natural Seawater Immersion on Compressive Properties of FRP Bars

针对天然海水浸泡条件下玻璃纤维增强复合材料(GFRP)筋、玄武岩纤维增强复合材料(BFRP)筋,开展了60℃恒温水浴加速老化试验以及抗压性能试验研究。基于试验结果,分析了不同浸泡时间对不同直径GFRP筋和BFRP筋受压破坏模式和抗压性能的影响。基于Weibull模型量化了GFRP筋和BFRP筋60℃恒温海水水浴后抗压强度的变异性。结果表明,60℃恒温海水侵蚀了FRP的表观面貌,90 d的抗压强度与弹性模量相对于0 d分别下降了13.06%和6.41%。在相同浸泡时间内,直径16 mm的FRP筋弹性模量比直径25 mm高4.17%,且直径相同的BFRP筋的弹性模量高于GFRP筋。Weibull模型量化了FRP筋试件抗压性能随海水浸泡时间变化的累积失效概率,准确捕捉抗压强度的变异性,为评估海水浸泡后FRP筋性能退化离散性提供了参考。

The accelerated aging test and compressive performance test of glass fiber reinforced polymer(GFRP)bars and basalt fiber reinforced polymer(BFRP)bars soaked in natural seawater at 60℃ were carried out.Based on the test results,the effects of different soaking time on the compression failure mode and compressive properties of GFRP bars and BFRP bars with different diameters were analyzed.Based on the Weibull model,the variability of compressive strength of GFRP bars and BFRP bars after 60℃seawater bath was quantified.The results showed that the appearance of FRP was eroded by 60℃constant temperature seawater,and the compressive strength and elastic modulus of 90 d decreased by 13.06%and 6.41%respectively compared with 0 d.In the same soaking time,the elastic modulus of FRP bars with a diameter of 16 mm was 4.17%higher than that of 25 mm,and the elastic modulus of BFRP bars with the same diameter was higher than that of GFRP bars.The Weibull model quantifies the cumulative failure probability of FRP bar specimens with the change of seawater immersion time,and accurately captures the variability of compressive strength,which provides a reference for evaluating the discreteness of FRP bar performance degradation after seawater soak.