Effect of CFRP location on flexural and axial behavior of SHS steel columns strengthened using CFRP

In recent years, the use of Carbon Fiber Reinforced Polymers (CFRP) for strengthening and retrofitting of steel structures has been considerably developed. Strengthening and retrofitting of structures have several reasons, including: design and calculation errors, lack of proper construction techniques, change in application after construction, damage caused by natural disasters such as floods and earthquakes, the occurring of fatigue cracking, metals corrosion, and so on. The column is an important member in building structures that has the duty to bear and transferring loads incurred to the structure. The stability in structural steel columns is very important. According to research conducted in literature, a few studies have done on the axial behavior of slender steel columns strengthened using carbon fiber reinforced composite. However, the main purpose of this study is to analyze the ultimate load of compressive and compressive-flexural (interaction loads) of square hollow section steel columns strengthened using composite carbon fiber with CFRP in different locations. For modeling and analysis of samples ANSYS software was used. 40 steel columns that strengthened using CFRP were analyzed by nonlinear static under axial compressive load. Three samples of the columns were also analyzed under compressive axial load and flexural moment interaction. The results showed that location, coverage percent and number of layers of CFRP are effective on the ultimate load of SHS steel columns under axial compression load and flexural moment. The results also showed that moving the location of the carbon composite with percentage of defined coverage can be have different effects on the axial compression load of steel columns.