EFFECTS OF WRAPPING WITH FIBER-REINFORCED POLYMER MATERIALS ON THE PERFORMANCE OF REINFORCED CONCRETE COLUMNS

Abstract

Aim: Increasing the resistance of reinforced concrete load-supporting components to external loads or restoring their original strength by utilizing fiber-reinforced composite materials has become an increasingly utilized technique in recent years. Because this process provides a wrapping effect on the concrete, it effectively boosts the element's strength and contributes to shear strength and energy absorption capacity. This paper presents the results of a comprehensive FEM investigation on the behavior of axially loaded square reinforced concrete columns with rounder corners that have been strengthened with carbon fiber-reinforced polymer CFRP wraps. First, a finite element model verified by experimental work, which allows laboratory experiments to be carried out in a computer environment, was obtained using ABAQUS software. 27 square reinforced concrete columns measuring 200*200*1100 mm were modelled and analysis was carried out using a non-linear finite element analysis. Three parameters of concrete strength, type of wrapping (full and partial) and the distance between stirrups were considered. According to the analysis results, significant increases were observed in the compressive strength of square reinforced concrete columns wrapped with CFRP compared to the unwrapped columns. It has been determined that full wrapping of the column increases the strength more than 3 times compared to ½ wrapping. It was found that the increase in ductility was relatively limited. Method: First, a numerical model of an experimental study from the literature was generated in the computer environment utilizing the non-linear finite element approach in this study. A parametric analysis was then performed to test the column strengths under various conditions in order to acquire extensive data. ABAQUS finite element software was used to examine all numerical models developed for the parametric study under axial load. Results: According to the parametric study results, fully wrapped columns performed significantly better than strip wrapped columns. It was determined that as the concrete strength increased, the strength of the confined columns increased more than twice. Conclusion: The numerical model implemented using ABAQUS finite element software confirmed the axial loaded column experiment obtained from the literature with an acceptable approximation. Parametric study conducted with the proposed finite element model showed that the percentage of wrapping with FRP composites plays an important role in increasing the axial load-carrying capacity of the column.