Study on the Corroded Hollow Section RC Columns Strengthened by ICCP-SS System
Study on the Corroded Hollow Section RC Columns Strengthened by ICCP-SS System
复制标题
ICCP-SS系统加固腐蚀空心截面RC柱研究
DOI：
10.3390/buildings11050197
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发表时间：
2021-05-01
期刊：
影响因子：
3.8
通讯作者：
Liu, Cheng-Bin
中科院分区：
文献类型：
--
作者：
Chen, Ju;Wang, Jun;Liu, Cheng-Bin
本文研究了外加电流阴极保护与结构加固体系(ICCP-SS)加固锈蚀钢筋混凝土空心柱的性能。碳纤维增强水泥基(C-FRCM)复合材料在干预方法中具有双重功能。通过轴心受压试验，首次研究了加固柱的轴压性能。分析了锈蚀率和C-FRCM加固对试验结果的影响，如破坏模式、荷载-位移曲线、极限荷载、极限应变等。试验结果表明，C-FRCM可以显著提高锈蚀试件的极限承载力，加固后试件的延性大于未加固试件，尤其是锈蚀率较高的试件。其次，采用电位滴定的方法分析了ICCP-SS体系对氯离子(Cl-−)在中空截面钢筋混凝土柱中迁移分布规律的影响。主要参数包括充电时间、电流密度和加盐量。结果表明，钢筋对Cl-−的迁移有一定的阻挡作用，导致钢筋内侧的Cl-−含量始终大于外侧，外加电流密度和充电时间的增加会降低钢筋两侧的Cl-−含量，而外加电流会使钢筋附近的Cl-−不断向碳纤维布附近移动。
In this paper, the behavior of corroded hollow section RC (reinforced concrete) columns strengthened by an Impressed Current Cathodic Protection and Structural Strengthening (ICCP-SS) system was investigated. The Carbon Fabric-Reinforced Cementitious Matrix (C-FRCM) composite serves dual functions in the intervention method. The axial compression behavior of strengthened columns was firstly investigated through axial compression tests. The influence of corrosion ratio and C-FRCM strengthening on the test results, such as failure mode, load–displacement curve, ultimate load, and ultimate strain, were analyzed. Test results showed that the ultimate load of the corroded specimens could be enhanced significantly by C-FRCM, and the ductility of the strengthened specimens was larger than the specimens without strengthening, especially for the specimens with higher corrosion ratios. Secondly, the effects of the ICCP-SS system on the migration and distribution laws of chloride ions (Cl−) in hollow section RC columns were analyzed by the potentiometric titration method. The main parameters include charging time, current density, and salt addition. Results showed that the rebar would have a certain blocking effect on the migration of Cl−, which resulted in that the content of Cl− in the inner side of the rebar was always larger than that of the outer side; and research results also showed that the increase of impressed current density and charge time would reduce the Cl− content on both sides of the rebar, while the impressed current would cause the Cl− near the rebars to constantly move toward the vicinity of CFRP.