硫酸盐干湿交替对碳纤维增强环氧树脂-混凝土界面粘结性能的影响

Influence of dry-wet alternation of sulfate on bonding performance of carbon fiber reinforced epoxy-concrete interface

为了研究硫酸盐腐蚀对碳纤维增强环氧树脂复合材料(CF/EP)-混凝土界面性能退化的影响。通过硫酸盐干湿交替加速腐蚀试验模拟硫酸盐环境,对硫酸盐腐蚀下CF/EP-混凝土界面粘结性能退化规律进行了研究。结果表明:硫酸盐干湿交替作用对CF/EP-混凝土界面的破坏形态影响较大;界面粘结性能(峰值剪应力、极限承载力和初始剪切刚度)随腐蚀时间呈先小幅增加后加速下降的趋势。在试验和已有界面理论的基础上,提出了考虑腐蚀时间的界面粘结-滑移模型,通过模型预测数据与试验数据的对比分析,该模型能够很好反映硫酸盐干湿交替作用下界面粘结性能退化规律。

In order to study the effect of sulfate corrosion on the degradation of interface properties of carbon fiber reinforced epoxy（CF/EP）-concrete.The sulfate environment was simulated by accelerated corrosion tests of cyclic dry-wet alternate.The degradation behavior of CF/EP-concrete interface under sulfite corrosion was studied.The results show that the effect of sulfate dry-wet alternation on the failure form of CF/EP-concrete interface is significant;the bond performance of interface increases slightly with the extending of corrosion time,and then decline accelerated.Based on the experiment and the existing interface theory,an interfacial bond-slip model is proposed,which is related to corrosion time.Through the comparison between the model predictions and the experimental data,the model can well reflect the degradation behavior of interfacial bonding performance under the dry-wet alternation of sulfate.