Seismic Vulnerability Assessment of Buildings in Northeast India

Abstract

Unreinforced masonry (URM) and reinforced concrete (RC) buildings are the most common newlinebuilding typology in the rural and urban areas of Northeast India. These buildings suffered newlinepartial damage to complete collapse during the earthquakes over the last decade. At this newlinebackdrop, this thesis evaluates the seismic vulnerability of low-rise URM and low to mid-rise newlineRC buildings primarily found in Northeast India. The effect of variability associated with the newlinegeometrical configuration and material properties of URM buildings is incorporated newlineconsidering a large number of data set. To quantify the influence of design and construction newlinequality (DCQ), infill wall distribution on seismic response, and vulnerability of RC buildings, newlinelow and mid-rise RC buildings with different DCQs and structural types are considered in this newlinethesis. The nonlinear static procedure (NSP) is used to generate capacity curves, and seismic newlinefragility analysis has been carried out to develop fragility curves. Fragility curves of URM newlinebuildings show a very high probability of suffering major to complete damage subjected to a newlinePeak Ground Acceleration (PGA) of 0.18g, which is used to design buildings in the newlineNortheastern region of India according to the Indian seismic code. The derived fragility curves newlineof URM buildings also give reasonable predictions of observed post-earthquake building newlinedamage and can be used for the earthquake risk assessment of the building of the same typology newlineof this region. The results of RC buildings show that inferior design and construction quality newlineand the absence of masonry infill on the ground floor increase susceptibility to the manifold. newlineHowever, through well design and construction practices, the vulnerability of these RC newlinebuildings with infilled masonry, and even the RC building with an open ground storey, can be newlinereduced. Consequently, the collapse of buildings can be avoided, at least for low seismic newlinehazards, which are repeatedly hitting the Northeastern region of the Indian subcontinent and newlinemany other countries. The result