Evaluating the Behavior of Welding-Defected CFRP Fiber-Reinforced Double-Channel Steel Columns

Document Type : Research Article


1 Master of Structures, Department of Civil Engineering, Zahedan Branch,, Islamic Azad University, Zahedan, Iran

2 Assistant Professor, Department of Civil Engineering, Zahedan Branch,, Islamic Azad University, Zahedan, Iran


Engineers have faced many structural problems in recent years, such as buckling, corrosion and excessive loading in damaged steel structures. The labor force's mistakes during welding and the destruction of the weld are among the many problems in steel structures. Therefore, strengthening and repairing the welding place in steel structures is inevitable. This article investigates the influence of polymers reinforced with carbon fibers for strengthening steel studded double columns with defects caused by welding. For this purpose, seven steel columns were modeled in Abaqus finite element software. A CONTROL column was modeled as the first sample with no defects and welded all over. The rest of the defective samples were reinforced using CFRP fibers. On the other hand, strengthening using CFRP fibers to improve the location of the defect was investigated in detail for three specimens. Reinforcement of these sections using CFRP fibers is not only an effective method to increase the maximum axial force in these columns, but it has also helped to improve resistance and delay local buckling in them. According to the results, it was observed that among all the samples, the maximum bearing capacity is related to the 2UW3 model, and it has increased by 29.9% and 21.7% in the laboratory sample and numerical modeling, respectively, compared to the 2UW3C1 sample. In addition, 2UW3C1 and 2UW1C1 samples have the highest hardness among laboratory and numerical modeling samples, respectively.


Main Subjects

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