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

Year 2020, Volume: 8 Issue: 1, 102 - 111, 28.01.2020

M. Nadir Olabi , Naci Çağlar , Nurdan G. Koroglu

https://doi.org/10.21541/apjes.584148

Abstract

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.

Keywords

Moment curvature, carbon fiber reinforced polymer, rectangular RC column, fiber model, GNU Octave

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