The effects of FRP fiber's elongation angles on strength behavior of RC beam-columns

Document Type : Research Paper

Authors

1 PhD student in Civil Engineering-Structure, Islamic Azad University, Central Tehran Branch, Faculty of Civil Engineering and Land Resources, Department of Structural Engineering

2 Civil department Civil and Earth Resources Engineering Faculty Tehran Central Branch Islamic Azad University Tehran- IRAN

3 Tarbiat Modares University

4 Assistant Professor, Islamic Azad University, Central Tehran Branch, Faculty of Civil Engineering and Land Resources, Department of Structure

10.22124/jcr.2023.20813.1521

Abstract

Strengthening of RC columns using FRP composites is done with the aim of increasing bearing capacity and ductility. One common method in this case is to enclose the entire outer surface of the column with FRP. In this paper, it has been done to strengthen this columns under eccentricity axial load, with the FRP layers. The specimens used have a circular cross-section with a diameter of 125 mm and a height of 800 mm, which are loaded in two cases by eccentricity. First case, the eccentricity is twice the radius of the column (2R) and the second case the eccentricity is four times the radius of the column (4R). Due to the eccentricity of the load, parts of the column are subjected to bending tension. Ten numerical models in two groups (2R and 4R) were analyzed using Abaqus software. In order to verify the accuracy of the modeling, first two existing experimental specimens were simulated with software and then the results were evaluated. The results showed that by increasing the eccentricity of the load, the longitudinal composites are more effected than transverse composites on force bearing and displacements. Also, the fiber has been effected on ductility increasing more than force tolerance in the column. In the 2R group, specimens with transverse composite have been increased about 14% in forcing and 15% in displacement capacities than longitudinal. Conversely, in the 4R group, the above mentioned numbers in samples with longitudinal composite increased by about 7% and 332% relative to transverse.

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References

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