The Chinese Journal of Nonferrous Metals
JOURNAL OF RAILWAY SCIENCE AND ENGINEERING
|第14卷 第2期 总第83期 2017年2月|
(大连理工大学 海岸和近海工程国家重点实验室，辽宁 大连 116024)
摘 要: 通过4点弯曲试验研究冻融循环作用下预应力CFRP(碳纤维增强聚合物)加固高强混凝土的耐久性。在非预应力试件为对比的基础上设置2种预应力等级，预应力分别为CFRP抗拉强度标准值的15%和30%。分析冻融循环和预应力对加固试件荷载-挠度曲线及破坏形态的影响，结果表明：冻融循环后加固试件的承载力均有不同程度的下降，预应力等级越高，承载力降低越显著；最大预应力等级试件的破坏形态由弯剪裂缝引起的剥离破坏发展为剪切剥离破坏。
（State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology, Dalian 116024, China）
Abstract:The four-point bending test was conducted to investigate the effects of freeze-thaw cycles on the durability of high strength concrete strengthened with prestressed CFRP (carbon fiber reinforced polymer). Two group of prestressed specimens were setup, and the tension control stress were equal to 15% and 30% of the standard value tensile strength of the CFRP. Another group of specimens strengthened with non-prestressed CFRP. The effects of freeze-thaw cycles and prestress were elaborated on the load-deflection curves and failure model. The results reveal that freeze-thaw cycles will lead to the decrease of the carrying capacity of all specimens. And the effect is gradually increasing with the increase of tension strength. The failure modes of specimens with the maximum level of prestress transformed from debonding of interface between CFRP and concrete were caused by flexural-shear crack to shear modes.
Key words: prestressed CFRP sheet; freeze-thaw cycles; bond behavior; debond failure