Abstract
•Studied axial compression behavior of wall-like RC column strengthened with CFRP.•Rectangular section of column was transformed to elliptical shape using mortar.•CFRP confinement increases concrete axial strength and strain capacity.•Strengthened column showed post-peak softening behavior.
The compression behavior of Carbon Fiber Reinforced Polymer (CFRP) strengthened wall-like rectangular reinforced concrete (RC) column after shape modification is presented. The research includes laboratory testing of rectangular RC columns externally confined by CFRP laminates after transforming the cross section into elliptical one using cement mortar. The finite element analysis was carried out to predict the load–displacement behavior of the test specimens.
Parametric studies pertaining to the effects of CFRP strengthening of wall-like columns on failure mode, strength, ductility, yielding of longitudinal and transverse reinforcement, confinement and dilatation are discussed. For the strengthened column, the stress–strain curve showed post-peak softening behavior. The CFRP confinement increases concrete axial compressive strength, but it is more effective in enhancing concrete strain capacity. The actual failure of the strengthened column was due to crushing of concrete and buckling of longitudinal rebars.
It is demonstrated that for cases where ductility and slenderness of the column are major issues, CFRP strengthening of columns after transforming the column cross section to elliptical one may be one of the cheapest mitigation solution.