Building Damage Assessment Using Scenario Based Tsunami Numerical Analysis and Fragility Curves

Khawar Rehman,Yong-Sik Cho

doi:10.3390/w8030109

Abstract

A combination of a deterministic approach and fragility analysis is applied to assess tsunami damage caused to buildings. The area selected to validate the model is Imwon Port in Korea. The deterministic approach includes numerical modeling of tsunami propagation in the East Sea following an earthquake on the western coast of Japan. The model is based on the linear shallow-water equations (LSWE) augmented with Boussinesq approximation to account for dispersion effects in wave propagation, and coastal wave run-up is modeled by non-linear shallow-water equations (NLSWE). The output from the deterministic model comprises inundation depth. The numerical output is used to perform fragility analysis for buildings vulnerable to flooding by tsunamis in the port area. Recently developed fragility curves—based on the ordinal regression method—are used for damage probability estimates. The extent of structural damage in the areas under a tsunami hazard is identified by the numerical modeling of tsunami features. Our numerical model offers high bathymetric resolution, which enables us to capture flow features at the individual structure level and results in improved estimation of damage probability. This approach can serve as a measure of assessing structure vulnerability for areas with little or no records of tsunami damage and provide planners with a better understanding of structure behavior when a tsunami strikes.

Highlights

Climate change and its increasing unpredictability, along with an increase in the population, have resulted in increased vulnerability of communities to disasters
The building damage data for Imwon Port are scarce; the area was severely affected by the tsunami and 44 buildings were destroyed, damaged, or flooded [32]
Since data on the number typography of the damaged structures at Imwon Port during the 1983 and 1993 tsunamis are not available, and typography of the damaged structures at Imwon Port during the 1983 and 1993 tsunamis are our structure damage estimates are based on fragility curves developed in a previous study [9]

Summary

Introduction

Climate change and its increasing unpredictability, along with an increase in the population, have resulted in increased vulnerability of communities to disasters. Frequent occurrences of floods caused by storms, torrential rains, and tsunamis have affected large swaths of the population all over the world in the past few decades. In the past two decades, 58 tsunamis with a maximum run-up height greater than 3 m were recorded around the world [1]. Areas hit by recent mega tsunamis experienced adverse effects in social structure and economic growth. The 2004 Indian Ocean Tsunami caused devastation in 11 countries, and the monetary damage was approximated around 10 billion US dollars with extensive infrastructure damage [2]. The 2010 Chilean tsunami and earthquake resulted in a few hundred causalities; 81,000 structures were destroyed and around 109,000 were severely damaged [3]

Methods

Results

Conclusion