A Complementary Engineering-Based Building Damage Estimation for Earthquakes in Catastrophe Modeling

Catastrophe modeling for earthquakes is conventionally designed as a probabilistic model to estimate the losses based on risk and vulnerability of a portfolio of exposures for a foreseeable set of events. This approach lacks a physical science of building damage that is linked to ground-shaking characteristics. A proposed engineering-based building damage estimation model based on established theories of seismic wave propagation and structural resonance is presented to address some of these shortcomings. A damage factor is introduced to provide an indication of the relative extent of damage to buildings. Analysis based on the proposed methodology is carried out using data derived from four case studies: the 2011 Tohoku earthquake; the 2007 Bengkulu earthquake; the 2011 Christchurch earthquake; and the 1999 Chi-Chi earthquake. Results show that the computed damage factors reasonably reflect the extent of actual damage to buildings that was observed in post-earthquake reconnaissance surveys. This indicates that the proposed damage simulation model has a promising future as a complementary assessment tool in building damage estimation in catastrophe modeling.