ANALYTICAL MODELING OF ECCENTRICALLY LOADED RC COLUMNS CONFINEDWITH FRP

Abstract

This paper presents an analytical research on behavior of columns confined with FRP subjected to axial load and uniaxial bending moment, by using finite element method and ANSYS-14.To indicate the accuracy of this program, five reinforced concrete columns strengthened with carbon fibers from the experimental testing of previous researches are re-analyzed by ANSYS program.The results showed that the percentage of experimental ultimate load to analytical ultimate load are (99.4, 99.6, 99.8, 97.5 and 97.2) %,and there is a reasonable agreement between the load-deflection curves for experimental and analytical results for all studied columns. The effects of important parameters on the ultimate load and the ductility of the column are studied.The results showed that the ultimate load and the ductility areincreased by 60.3% and 118.8% as the compressive strength increased from 22 MPa to 40Mpa.The study shows, that the increasing in CFRP layers lead to increasing in the ultimate load and the ductility of the column, The maximum increasing in the ultimate load and ductility for the column are 78% and 69.4% respectively.The results showed that ,the ultimate load and the ductility are increased by 24.1% and 23% respectively when the percentage of steel area is increased from 1% to 4%.Finally, loads with several eccentricities from the center of the column are studied, the results show a significant reduced value in the ultimate load for confined column by 51% at load eccentricity value equal to 125mm.While the column ductility reduced to 42% for the same load eccentricity.