无机胶凝材料粘贴碳纤维布加固混凝土结构研究进展

Progress of research on concrete structures strengthened with CFRP sheets bonded with inorganic cementitious materials

总结了近年来用无机胶凝材料粘贴碳纤维布加固混凝土结构的研究进展,包括各种无机胶凝材料(碱激发胶凝材料、氯氧镁水泥和水泥基复合材料)的分类与起源,碳纤维布常温与高温力学性能,以及无机胶凝材料加固混凝土结构常温与抗火性能等,指出了无机胶凝材料在加固技术中尚存在的一些问题,如各种无机胶凝材料的极限变形能力尚显不足等。分析结果表明:碱激发胶凝材料可耐600℃高温,氯氧镁水泥可耐300℃高温,且二者黏结加固效果均优于水泥基复合材料;常温下无机胶凝材料的粘贴加固效果与环氧类有机胶大体相当,高温下其加固效果明显优于环氧类有机胶,因此,用无机胶凝材料粘贴碳纤维布加固混凝土结构并以此提高结构的承载力是可行的;用无机胶凝材料粘贴碳纤维布加固混凝土结构的耐久性及其抗火设计方法等,应是今后一段时间建筑结构加固领域值得关注的课题。

This paper summarized the progress of research on concrete structures strengthened with CFRP sheets bonded with inorganic cementitious materials（ICM） in recent years,and discussed some issues that still need to be investigated,such as the inadequate ultimate deformation capacity of ICM.The progress mainly includes the classification and origin of all kinds of ICM（such as alkali-activated cementitious materials（AACM）,and magnesium oxychloride cement（MOC）,as well as engineered cementitious composites（ECC） and so on）,the mechanical properties of CFRP sheets at ambient and elevated temperatures,and the room-temperature and fire-resistant properties of concrete structures strengthened with CFRP sheets bonded with ICM,etc.Analysis result shows that the AACM can withstand 600 ℃,and the MOC can sustain 300 ℃.Moreover,the strengthening effects of both AACM and MOC are better than that of ECC.The strengthening effect of ICM is comparable to that of organic adhesive at ambient temperature,and the former is obviously better than the latter at elevated temperature.It is feasible to strengthen concrete beams and slabs with CFRP sheets bonded with inorganic cementitious materials in order to enhance the bearing capacity of reinforced concrete structures.Durability and fire design method of concrete structures strengthened with inorganic cementitious materials are the main problems for structural strengthening and need to be studied in the future.