Seismic Behavior of Exterior RC Beam-Column Joints Retrofitted using CFRP Sheets

The seismic behavior of full-scale exterior reinforced concrete (RC) beam-column joints retrofitted with externally bonded Carbon Fiber Polymers (CFRP) is examined in this paper. Casting and testing of two similar reinforced concrete beam column connections in the absence of transverse reinforcement at the joints took place under opposing cyclic loading with regulated displacement so as to examine their fundamental seismic performance. The first joint was examined as the control specimen and the other specimen was then retrofitted with CFRP sheets, with rounded border of the column and beam at and close to the joint region to change them from square to squircle segments. It is demonstrated in the experimental findings that the retrofitted beam column joint shows significantly greater strength, energy dissipation and ductility in comparison to the control specimen. There was a shift in the failure from the joint region to the beam ends in the retrofitted specimens, which would help in preventing the structure from disintegrating progressively. Because of the change in the beam and column from square to squircle segments, the debonding potential of the CFRP decreased and the restrictive impact of the CFRP increased. As a result, the experimental findings were verified using a 3D nonlinear finite element (FE) model. When the finite element and experimental findings are compared, it is determined that the suggested model is quite accurate.