通过18个表层嵌贴CFRP-混凝土拔出试件的试验,考察了不同冻融循环次数下有着不同CFRP埋深的试件的粘结承载力、破坏模式以及CFRP的应变分布等,分析了不同冻融循环次数下嵌贴CFRP-混凝土界面的粘结行为;以及在冻融循环作用下,不同CFRP板条埋深对嵌贴CFRP粘结性能的影响。试验结果表明:随着冻融循环次数的增加,试件的破坏模式由CFRP板的拉断破坏转变为试件粘结界面的破坏,试件的粘结承载力呈下降趋势,冻融侵蚀对CFRP-混凝土界面粘结性能产生了明显的劣化作用;在室温环境下,CFRP埋置深度对CFRP-混凝土界面粘结性能影响不明显;在冻融循环作用下,CFRP板条埋置深度为10mm时,其CFRP-混凝土界面粘结性能受冻融循环侵蚀的劣化作用较其他试件更明显。
In this paper, through experiment of 18 pull-out concrete specimens with surface mounted CFRP strip, the bond capacity, failure mode and CFRP strain distribution of specimen with different CFRP buried depths and subjected to different times of freezing-thawing cycle action were explored. The bond behavior of the interface between concrete and mounted CFRP strip and the effect of buried depth on CFRP bond property are analyzed respectively under different times of freezing-thawing cycle. Experimental results show that along with the increase of times of freezing-thawing cycle, the failure mode of specimen transforms from the tensile fracture into the bond interface damage, the bond capacity decreases. So, freezing-thawing erosion produces obvious deterioration effect on CFRP- concrete interface. At room temperature, the effect of CFRP buried depth on bond property of CFRP- concrete interface is not obvious. Under freezing-thawing action, when the buried depth of CFRP strip is 10mm, the deterioration effect is more obvious than other buried depths (16mm and 30mm).