Seismic Rehabilitation of Exterior RC Beam-Column Joints Using Steel Plates, Angles, and Posttensioning Rods

Abstract

The presented studies have been conducted on the scope and magnitude of damages inflicted by earthquakes over the years. Many RC buildings, designed and constructed in the 1960s and 1970s, have serious structural deficiencies, especially in their beam-column joints. Such deficiencies result from inadequate joint shear strength or confinement of column reinforcement. The joints require elaborate retrofit measures to ensure the performances comparable to those of new designed structures. In this research, a new seismic retrofitting method is presented for beam-column joints based on the two-dimensional enlargement of the joint by using steel plate, angles, and posttensioning rods. The seismic adequacy of deficient RC beam-column joints, and the efficacy of steel plates and posttensioning rods, have been investigated for retrofitted joints through experimental and numerical analyses. According to the results obtained through investigations, this new rehabilitation scheme is effective, simple to install, and nondisruptive to the function of the building. The behavior of the experimental results has also been successfully predicted by a finite-element model.