A refined procedure for seismic evaluation and retrofitting of reinforced concrete buildings

In the present study, a refined procedure for the seismic evaluation and retrofitting of reinforced concrete (RC) buildings based on the ‘quadrants assessment method’ and ‘material strain limit approach’ is proposed and numerically analysed. The quadrants assessment method involves the performance point, design base shear and threshold damage limit state. Herein, four existing RC buildings (models 1–4) are considered from the Koyna–Warna region, Maharashtra (zone-IV, India). These four buildings were studied using nonlinear static ada­ptive pushover analysis employing the SeismoStruct software. Based on the quadrants assessment method, the three-storey RC building (model-1) was retrofitted with RC jacketing, while the other three RC buildings did not need to be retrofitted. Also, significant seismic design parameters like ductility, over strength factor, response reduction factor, etc. were evaluated before and after retrofitting. The results depict that the combi­nation of the ‘quadrants assessment method’ and ‘mate­rial strain limit approach’ is a rapid, reliable and refined procedure for seismic evaluation and retrofitting of RC buildings