碳纤维板-混凝土界面黏结性能的试验研究与有限元分析  

Experimental Research and Finite Element Analysis of the Interfacial Bonding Behavior of CFRP-Concrete Interface

作　　者：尚守平[1] 李知兵[1,2] 彭晖[3] 

机构地区：[1]湖南大学土木工程学院,湖南长沙410082 [2]湖南工学院建筑工程与艺术学院,湖南衡阳421002 [3]长沙理工大学土木与建筑学院,湖南长沙410004

出　　处：《湖南大学学报（自然科学版）》2014年第6期43-51,共9页Journal of Hunan University:Natural Sciences

基　　金：国家十二五科技支撑计划项目(2011BAJ08B02);国家自然科学基金资助项目(51008036);湖南省科技计划重点项目(06sk4057)

摘　　要：碳纤维板与混凝土的界面黏结性能是碳纤维加固混凝土结构的关键性能之一,对加固结构的力学行为和破坏形态等有着重要影响.进行了4个试件的碳纤维板-混凝土黏结双面剪切试验,研究了设置不同粘贴长度的试件的界面力学行为和破坏模式,分析了黏结长度对界面极限承载力和应力分布的影响.试验结果表明:加载点附近应力远大于端部应力,板端黏结界面剪应力沿板长方向大致呈指数衰减分布.在试验研究基础上,在ANSYS中采用正交弹簧单元组模拟界面黏结,建立了试件的有限元模型,并采用试验分析得到的局部黏结滑移曲线关系作为有限元模型中的界面弹簧单元刚度,计算发现有限元分析结果和试验结果比较吻合,从而验证了本文有限元模型的有效性.以本文试验得到的黏结滑移曲线关系为基础,通过拟合得到了基于几种经典黏结滑移本构形式的界面本构模型.试验及有限元分析表明:当拉伸应力超过碳纤维板强度的24%时,碳板已开始从混凝土表面剥离.为保证充分利用碳纤维板的强度,应采用可靠锚具对碳纤维板进行锚固.The bonding behavior of CFRP-Concrete Interface is a key performance of concrete structure strengthened with CFRP plate, and it has a critical effect on the mechanical behavior and the failure mode of the strengthened structure. This paper adopted double-shear tests on 4 concrete components strengthened with CFRP plate to investigate the mechanical behavior and the failure mode of the specimens with different bond length and to analyze the influence of different bond lengths on the ultimate capacity and the distribution of the bonding stress. According to the test results, the distribution of the CFRP strain along the bond length shows an exponential decreasing law, and the stress near the loading position is much greater than the other end. The orthotropic spring elements were adopted to simulate the adhesive layer with ANSYS software, and the finite element model of the specimen was established. The local bond slip curve obtained from the test was used as the F-d curve of spring elements. The FEA results agree with the experimental ones, confirming the correctness of the FEM. Based on the bond slip curves obtained from the test, some bond-slip constitutive relationships were fitted according to several classic bond-slip consti- tutive relations. The test and FEA results show that the CFRP plate has begun peeling from the concrete surface when the tensile stress applied to CFRP reaches 24% of the tensile strength of the material. To ensure the full utilization of CFRP strength, the anchorage for CFRP plate should be adopted.

关 键 词：碳纤维板 界面 黏结性能 剪切试验 有限元方法 

分 类 号：TU318[建筑科学—结构工程]