Vulnerability Assessment for Seismic Strengthening of an Existing School Building in the Region of High Seismicity

Recent studies highlight the majority of existing structures located in the seismic-prone regions all over the world often found to be designed with poor or without the consideration of the seismic designs and/or are variously incompetent in the sight of the principles of seismic designs used currently. Earthquakes, even with a moment magnitude of 6.0 are capable of causing extensive loss of structural compatibility and hence structures need to be evaluated in the sight of the current codes available and provisions of retrofitting should be incorporated, if necessary. In this study, a school building located in Imphal, Manipur was considered and conducted a vulnerability assessment through incorporation of preliminary and detailed assessment analysed by ETABS 2018 software with Pushover analysis. Then the actual model was modified to three different models by keeping intact the materials and section details same as the actual model to study how change in geometrical configuration impacted the structural integrity. Formation of Plastic Hinges through Pushover analysis were pre-eminently considered towards Collapsed Prevention (CP) level. The structural elements with CP level hinges were then retrofitted by using RC jacketing, steel jacketing, and bracings. The deflections from the retrofitting processes were compared to the actual model and the pushover curves were then used to carry out an assessment study and evaluate the effectiveness of the strengthening programme.