冻融循环和界面持续应力作用下CFRP-混凝土界面的粘结性能研究*
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（1 长沙理工大学土木与建筑学院， 长沙 410114; 2 长沙理工大学桥梁工程安全控制教育部重点实验室， 长沙 410114; 3 湖南工学院建筑工程与艺术设计学院， 衡阳 421002)［摘要］通过对12根试验梁进行冻融循环作用下预应力CFRP板加固钢筋混凝土梁的界面粘结性能试验研究，考察了CFRP板初始应力水平、冻融循环次数及混凝土强度等因素对CFRP-混凝土界面粘结性能的影响。试验结果表明：随着冻融循环次数的增加，加固试件界面粘结应力的劣化速率逐渐增大，薄弱环节逐渐由混凝土保护层向粘结界面发展；CFRP板初始应力和冻融循环的耦合作用对粘结界面的劣化效应较单一的冻融循环作用更加显著，而且随着CFRP板初应力水平的增加，这种劣化效应会逐渐加剧；混凝土强度等级为C60的预应力CFRP板加固试件在冻融侵蚀作用下的界面粘结性能退化速率较C30加固试件更加显著。［关键词］预应力CFRP板; 钢筋混凝土梁; 冻融循环; 持续界面应力; 粘结性能中图分类号：TU378文献标识码：A文章编号：1002-848X(2015)09-0098-05Bond performance study of CFRP-concrete interface under freeze-thaw cycling and sustained interfacial stressFu Junjun1, Peng Hui1,2, Mo Yongxiang1, Li Zhibing3(1 School of Civil Engineering and Architecture, Changsha University of Science & Technology, Changsha 410114, China;2 Ministry of Education Key Laboratory of Safety Control of Bridge Engineering, Changsha University of Science & Technology, Changsha 410114, China; 3 College of Construction Engineering and Arts, Hunan Institute of Technology, Hengyang 421002, China)Abstract: Interfacial bond performance experiments of total 12 reinforced concrete beams, which were strengthened with prestressed CFRP plates, were conducted under freeze-thaw cycling. The influences of CFRP initial stress level, freeze-thaw cycling times and concrete strength on the interfacial bond performance of the strengthened specimens were analyzed. Experimental results show that with the increasing of freeze-thaw cycling times，the degradation of interfacial bond stress is gradually significant and the weak zoom transforms from concrete to bond interface gradually. The coupling effect of initial stress and freezing-thaw cycling on the interfacial bond performance is severity to the signal effort of freeze-thaw cycling，and it becomes worse with the increasing level of initial stress level. The degradation of strengthened specimens with concrete strength of C60 under freeze-thaw cycles is more significant than that of specimens with concrete strength of C30．Keywords: prestressed CFRP plate; reinforced concrete beam; freeze-thaw cycling; sustained interfacial stress; bond performance*国家重点基础研究发展计划项目（2015CB057701），国家自然科学基金项目（51008036），湖南省教育厅科学研究重点项目（14A005），桥梁结构安全控制湖南省工程实验室开放基金重点项目（14KD01），现代公路交通基础设施先进建养技术协同创新中心项目。作者简介：付俊俊，硕士研究生，Email：fujunjn@163.com。参考文献［1］YUN Y, WU Y F. Durability of CFRP-concrete joints under freeze-thaw cycling［J］. Cold Regions Science and Technology, 2011, 65(3): 401-412.［2］任慧韬, 胡安妮, 赵国藩. 冻融循环对玻璃纤维布加固混凝土梁受力性能影响［J］. 土木工程学报, 2004, 37(4): 104-110.［3］SHI J, ZHU H, WU Z, et al. Bond behavior between basalt fiber-reinforced polymer sheet and concrete substrate under the coupled effects of freeze-thaw cycling and sustained load［J］. Journal of Composites for Construction, 2012, 17(4): 530-542.［4］GREEN M F, BISBY L A, BEAUDOIN Y, et al. Effect of freeze-thaw cycles on the bond durability between fibre reinforced polymer plate reinforcement and concrete［J］. Canadian Journal of Civil Engineering, 2000, 27(5): 949-959.［5］王苏岩, 尹晓明, 刘林. 冻融环境下 CFRP-高强混凝土抗剪性能试验研究［J］. 建筑结构学报, 2008，29(S1): 176-180.［6］WAN B, PETROU M F, HARRIES K A. The effect of the presence of water on the durability of bond between CFRP and concrete［J］. Journal of Reinforced Plastics and Composites, 2006, 25(8): 875-890.［7］SUBRAMANIAM K V, ALI AHMAD M, GHOSN M. Freeze-thaw degradation of FRP-concrete interface: impact on cohesive fracture response［J］. Engineering Fracture Mechanics, 2008, 75(13): 3924-3940.［8］VERGHESE K, HARAMIS J, PATEL S, et al. Enviro-mechanical durability of polymer composites［M］// Long Term Durability of Structural Materials. Amsterdam:Elsevier Science Ltd., 2001: 121-131.［9］AGARWAL A, FOSTER S J, HAMED E, et al. Influence of freeze-thaw cycling on the bond strength of steel-FRP lap joints［J］. Composites Part B: Engineering, 2014, 60: 178-185.［10］李趁趁, 黄承逵, 高丹盈. 特定环境下 FRP 与混凝土正拉黏结性能试验研究［J］. 大连理工大学学报, 2006，46（IS）: 77-81.［11］王苏岩, 尹晓明, 刘林. 持载作用下 CFRP-高强混凝土界面的抗冻性能［J］. 沈阳建筑大学学报: 自然科学版, 2009, 25(5): 834-841.［12］任慧韬, 李杉,高丹盈. 荷载和恶劣环境共同作用对 CFRP-钢结构黏结性能的影响［J］. 土木工程学报, 2009，43(3): 36-41.［13］LAOUBI K, EL-SALAKAWY E, BENMOKRANE B. Creep and durability of sand-coated glass FRP bars in concrete elements under freeze/thaw cycling and sustained loads［J］. Cement and Concrete Composites, 2006, 28(10): 869-878.［14］HMIDAN A, KIM Y J, YAZDANI S. Effect of sustained load combined with cold temperature on flexure of damaged steel beams repaired with CFRP sheets［J］. Engineering Structures, 2013, 56: 1957-1966.［15］SOLIMAN S M, EL-SALAKAWY E, BENMOKRANE B. Bond performance of near-surface-mounted FRP bars［J］. Journal of Composites for Construction, 2010, 15(1): 103-111.［16］CERONI F, PECCE M, BILOTTA A, et al. Bond behavior of FRP NSM systems in concrete elements［J］. Composites Part B: Engineering, 2012, 43: 99-10.
