Structural score to quantify the vulnerability for quick seismic assessment of RC framed buildings in India

摘要

Seismic vulnerability assessment of existing RC frame buildings is important for evaluating their performance to future earthquakes and accordingly plan risk mitigation strategies. Preliminary assessment technique is commonly used to quickly assess the vulnerability based on a sidewalk survey of a building. Majority of existing techniques only provide qualitative results which generally lead to difficulty in classifying building as vulnerable or not. A preliminary assessment method based on HAZUS has been developed for RC frame buildings designed as per Indian standards considering seismicity, soil conditions, frame-type and irregularities as main variables. The proposed technique provides both qualitative and quantitative assessment in a more engineered way by assigning a structural score to a building, which essentially defines its probability of collapse. Nonlinear-static pushover analysis has been performed on certain archetype buildings using open source software (OpenSEES) to develop the structural score of a building. Most commonly observed irregularities such as open ground storey, severe vertical irregularity, short-column and plan irregularity are considered for evaluating the structural score. The proposed structural score helps in taking a step forward to quickly quantify the vulnerability of RC framed buildings in India.