Seismic fragility of structural and non-structural elements of Nepali RC buildings

This study presents seismic fragility functions of reinforced concrete buildings affected by the 2015 Gorkha Earthquake in Nepal. The fragility functions are based on detailed damage inspection of a large number of buildings affected by the earthquake and its aftershocks. For the first time, an attempt is made to quantify seismic fragility of Nepali RC buildings at both global and component level. While global fragility functions are useful in overall loss estimation, component level fragility functions are useful in identifying weak links in structures and are useful for overall risk mitigation. The results show that Nepali RC buildings, even those constructed after implementation of Nepal Building Code, pose significant risk of damage during moderate to strong shaking. At peak ground acceleration of 0.3–0.4 g, about 50% of the buildings may be damaged beyond immediate occupancy. It is also observed that beam-column connections are the most fragile structural components of these buildings. Non-structural components such as infill walls and parapet walls are more fragile than structural components and pose safety threat to occupants not to mention disruption of functional use the buildings.