M Nadir OLABİ, Nurdan G. KOROGLU, NACİ ÇAĞLAR

Numerical Investigation for Moment-Curvature Relationship of CFRP Jacketed RC Columns

External jacketing of columns with Carbon Fiber Reinforced Polymer (CFRP) sheets is one of the most commonly used techniques to strengthen the existing reinforced concrete (RC) columns subjected to earthquake loads. In this paper, a parametric study is performed to examine the effects of CFRP jacketing, axial load levels and concrete quality on the total response of the CFRP jacketed RC columns. The newly computer code was developed to determine moment-curvature relationships of CFRP jacketed RC columns. Moment curvature analysis is carried out using three column sections with a fixed reinforcement ratio and three different concrete qualities, and also three different thicknesses of the CFRP wraps. The performance of jacketed RC columns in terms of ductility, strength, stiffness and energy dissipation is investigated. The results of the parametric study showed that strengthening RC columns with CFRP wraps has a significant effect on the total response of jacketed columns due to the confinement of concrete. However, the degree of enhancement in total response is also related to axial load levels.

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