纤维增强聚合物加固混凝土结构耐久性能研究

外贴纤维增强聚合物(FRP)加固混凝土结构的应用时间不长,因此这种加固方法的耐久性能需要试验验证.通过快速冻融试验、碱化试验、浸水试验、湿热试验研究了腐蚀环境对纤维增强聚合物复合体力学性能的影响.试验结果表明,碳纤维增强聚合物(CFRP)的耐久性能较好,在各种暴露条件下,力学性能没有明显退化;而玻璃纤维增强聚合物(GFRP)的耐久性能略差,水环境、碱环境、湿热环境以及冻融循环对GFRP均产生了较大的影响.采用快速冻融循环试验和湿热试验,研究了腐蚀环境对FRP与混凝土粘结性能、FRP加固混凝土梁、柱受力性能的综合影响.结果表明:FRP与混凝土粘结性能下降较大,FRP加固混凝土结构具有较好的耐久性能.

Research on durability of concrete structures strengthened with FRP laminates

Durability experiments are required to verify the long-term safety and effectiveness for the strengthening method because of the short time application in retrofitting concrete structures.Based on the fast freeze-thaw test,the alkaline test,the water immersion test and the wet-thermal test,the influence on the mechanical behavior of FRP(fiber reinforced polymer) caused by aggressive environments was studied.CFRP(carbon fiber reinforced polymer) specimens subjected to aggressive environment showed good durability with no significant degradation in tensile strength and modulus;however,GFRP(glass fiber reinforced polymer) specimens exhibited a little decrease in mechanical property after aggressive environments exposure.Based on the fast freeze-thaw test and the wet-thermal test,the influence on bond behavior between FRP and concrete,mechanical behavior of concrete beam and column strengthened with FRP caused by aggressive environments was studied.The results show that the bond strength has a significant decrease compared with those specimens kept at room temperature,and the specimens strengthened with FRP exhibit good durability.