摘要
采用单搭接头剪切试验比较FRP-混凝土界面使用不同树脂黏结剂在不同浸水时长下的剪切黏结强度、破坏模式、剪切断裂能、黏结滑移曲线等黏结特性。最大6个月的20℃浸水试验表明,采用多乙烯多胺混合硬化树脂的界面黏结强度降低了11%～14%,采用多胺硬化树脂的界面黏结强度降低了2%～10%,黏结层断裂能和局部最大剪应力也有所降低。浸水后的界面破坏模式由浸水前的混凝土黏聚层转移为界面黏着层,这表明浸水条件下界面黏着力降低。同时,树脂黏结材料的材料试验结果表明,树脂本身的抗拉强度在浸水6个月后有所提升,而剪切黏结强度只有微小降低。局部黏结滑移关系的计算结果表明浸水后最大局部剪切应力有所降低,同时界面的平均剪切断裂能降低26%。
Single lap shear bond test was conducted to compare the ultimate bond strength,failure modes,fracture energy,bond stress-slip curves with and without water immersion at different exposure periods and epoxy primers.The results until 6 months exposure period revealed that bond strength decreased around 11% ~14% for Type-E（polyphenol-polyamine combined hardener epoxy resin） specimens and 2%~10% for Type-F（polyamine hardener epoxy resin） specimens when subjected to continuous immersion in water at 20℃.The study also observed that decrease fracture energy and peak bond stress after water immersion.Further,the bond failure of FRP-concrete interface occurred at the primer-concrete layer showing loss in adhesion properties after exposure in water.In addition to this,material test were also conducted to determine the effect of water on the mechanical properties（tensile,shear,Young’s modulus） of resins used.The tensile strength of the resins after water immersion were found higher in most of the cases irrespective of period of immersion whereas the shear test of the resins showed little decrease in strength after six months of continuous immersion.Both the peak shear stress and fracture energy decreased with increasing immersion period.
出处
《施工技术》
CAS
北大核心
2013年第10期34-38,共5页
Construction Technology
基金
浙江大学"紫金计划"资助项目(188020+1934326041/016)
