On February 27, 2010, a megathrust earthquake of Mw 8.8 (USGS) provoked a destructive tsunami in Chile. The tsunami damaged about 600 km area along the coast of Chile, including the coastal towns of Dichato and Tumbes in the Bio-Bio region and Robinson Crusoe Island on the archipelago of Juan Fernandez, about 670 km off the coast of Chile. To estimate the structural damage in a quantitative manner for the areas mentioned, tsunami fragility functions were developed. Using Tohoku University's Numerical Analysis Model for Investigation of Near-field tsunamis (TUNAMI) for the numerical simulation to obtain the propagation and inundation depths and visual inspection of satellite images for the damage data, the fragility curves for Juan Fernandez, Tumbes, and Dichato were constructed. The obtained curves suggest that for an inundation depth of one meter, the damage probability is 7%, 48%, and 82% for Tumbes, Dichato, and Juan Fernandez, respectively. The similarity of the construction type (wood, masonry, and mixed) indicates that the areas' exposure and building configuration has the most significant impact on the structural damage, considering that Juan Fernandez island was not affected by the ground motion of the 2010 event.
Keywords: Tsunami, Fragility function, 2010 Maule Earthquake, Chile