Structural behaviors of deficient steel CHS short columns strengthened using CFRP

Steel structures may need.rehabilitation and restoration due to different reasons including design and calculation errors, lack of proper implementation, change in application, damage as a result of random loads, exhaustion and corrosion, and natural disasters such as earthquakes, fires, and environmental conditions. Carbon Fiber Reinforced Polymer (CFRP) is one of the advanced materials for strengthening structures. This study aims to examine the structural behaviors and impact of CFRP on strengthening steel Circular Hollow Section (CHS) short columns with initial horizontal or vertical deficiency. A total of six steel CHS columns were studied in laboratory, and the same plus two more specimens were modeled using ABAQUS software. Static gradual compression force was applied in laboratory, and the Riks Non-Linear Analysis Method was utilized in simulation to observe the plastic zone buckling after post buckling. The results showed that deficiency led to reduce bearing capacity of steel columns and the impact of horizontal deficiency was higher than the vertical one. Using CFRP for strengthening deficient columns showed that CFRP yielded appropriate impact on rising bearing capacity rise, reducing stress in the damage location, and preventing local deformation (local buckling) around the deficiency appropriately. (C) 2017 Elsevier Ltd. All rights reserved.