Experimental analysis of RC rectangular and square columns confined using carbon fiber composites

Abstract

Most of the places around the world are associated with the deterioration of major components such as columns in the reinforced concrete buildings or structures. The inventive strengthening and rehabilitation techniques for reinforced concrete structures and components, specifically with fiber composites, have occupied a huge part of the investigation work in the arena of restoration and repair of structural components. The technique of strengthening RC columns by means of carbon fiber composite is widely used due to its excellent properties compared to other FRP sheets. Many research works were directed in the field of strengthening reinforced concrete circular columns. However, other cross-section shapes like rectangular or square columns did not take the same attention which is mostly preferred in actual constructions. The main focus of this present work is to study the comparative axial behavior of square and rectangular columns after strengthening with carbon fiber composite through experimental investigations. The experimental analysis comprised twelve reinforced concrete (RC) columns consisted of unwrapped and carbon fiber composite wrapped. The axial response of rectangular and square was recognized through the evaluation of outcomes in the form of axial strengths, ductility and failure patterns. The experimental outcomes exhibited that the effect of confinement on square columns significantly improves the strength-ductility behavior compare with confined rectangular columns. The comparative study exposes the variations in cracking patterns at failure loads on rectangular and square RC columns confined with carbon fiber composite. It is also observed that the axial behaviors of unwrapped and wrapped RC columns are significantly affected by the change in shape.