Developing fragility functions for the areas affected by the 2009 Samoa earthquake and tsunami

Abstract. Fragility functions in terms of flow depth, flow velocity and hydrodynamic force are developed to evaluate structural vulnerability in the areas affected by the 2009 Samoa earthquake and tsunami. First, numerical simulations of tsunami propagation and inundation are conducted to reproduce the features of tsunami inundation. To validate the results, flow depths measured in field surveys and waveforms measured by Deep-ocean Assessment and Reporting of Tsunamis (DART) gauges are utilized. Next, building damage is investigated by visually interpreting changes between pre- and post-tsunami high-resolution satellite images. Finally, the data related to tsunami features and building damage are integrated using Geographic Information System (GIS), and tsunami fragility functions are developed based on the statistical analyses. From the developed fragility functions, we quantitatively understood the vulnerability of a coastal region in American Samoa characterized by steep terrains and ria coasts.

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Developing fragility functions for the areas affected by the 2009 Samoa earthquake and tsunami

Natural Hazards and Earth System Sciences Discussions ◽

10.5194/nhessd-2-1-2014 ◽

2014 ◽

Vol 2 (1) ◽

pp. 1-25

Author(s):

H. Gokon ◽

S. Koshimura ◽

K. Imai ◽

M. Matsuoka ◽

Y. Namegaya ◽

...

Keyword(s):

Satellite Images ◽

Hydrodynamic Force ◽

Deep Ocean ◽

Building Damage ◽

Fragility Functions ◽

Tsunami Propagation ◽

Tsunami Inundation ◽

Field Surveys ◽

High Resolution Satellite Images ◽

Tsunami Fragility

Abstract. Fragility functions in terms of flow depth, flow velocity and hydrodynamic force are developed to evaluate structural vulnerability in the areas affected by the 2009 Samoa earthquake and tsunami. First, numerical simulations of tsunami propagation and inundation are conducted to reproduce the features of tsunami inundation. To validate the results, flow depths measured in field surveys and waveforms measured by Deep-ocean Assessment and Reporting of Tsunamis (DART) gauges are utilized. Next, building damage is investigated by manually detecting changes between pre- and post-tsunami high-resolution satellite images. Finally, the data related to tsunami features and building damage are integrated using GIS, and tsunami fragility functions are developed based on the statistical analyses.

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Development of Tsunami Fragility Functions for Ground-Level Roads

Journal of Disaster Research ◽

10.20965/jdr.2017.p0131 ◽

2017 ◽

Vol 12 (1) ◽

pp. 131-136 ◽

Cited By ~ 1

Author(s):

Yoshihisa Maruyama ◽

◽

Osamu Itagaki

Keyword(s):

Pacific Coast ◽

Tohoku Earthquake ◽

Ground Level ◽

Fragility Functions ◽

Tsunami Propagation ◽

Tsunami Inundation ◽

Fragility Function ◽

Simulation Results ◽

Tsunami Fragility ◽

The Relationship

In exploring the relationship between ground-level road damage ratios and tsunami inundation depths following the 2011 Pacific Coast Tohoku earthquake in Japan, we focused on road damage components, excluding elevated roads, bridges, and tunnels. The damage ratio is defined as the number of damage incidents per kilometer. We used the damage dataset compiled by the Japanese Ministry of Land, Infrastructure and Transport. We propose four fragility function zones for ground-level roads based on differences in topographical features. We studied these zones based on numerical simulation results of tsunami propagation.

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Scenarios of Earthquake and Tsunami Damage Probability in Callao Region, Peru Using Tsunami Fragility Functions

Journal of Disaster Research ◽

10.20965/jdr.2014.p0968 ◽

2014 ◽

Vol 9 (6) ◽

pp. 968-975 ◽

Cited By ~ 8

Author(s):

Bruno Adriano ◽

◽

Erick Mas ◽

Shunichi Koshimura ◽

Miguel Estrada ◽

...

Keyword(s):

Building Damage ◽

Disaster Mitigation ◽

Fragility Functions ◽

Building Structures ◽

Tsunami Inundation ◽

Damage Probability ◽

Historical Tsunami ◽

Unit Scale ◽

Hazard Scenario ◽

Tsunami Fragility

The implementation of adequate urban development and measures systems against tsunami impact in coastal communities is improved by understanding damage probability among building structures. Within the framework of the project Enhancement of Earthquake and Tsunami Disaster Mitigation Technology in Peru (JST-JICA SATREPS), the authors analyze the damage probability of building structures due to tsunami impact in the Callao region of Peru. Two different tsunami hazard scenarios are assumed in assessing building damage probability. The first tsunami scenario represents the worse-case scenario of tsunami inundation that calculates the envelop of maximum inundation depth and flow velocity values from 12 probabilistic megathrust earthquake scenarios for central Peru. The second tsunami scenario corresponds to a historical tsunami event in this region. We apply a methodology for evaluating different levels of building damage by combining tsunami numerical results and tsunami fragility functions. Damage probability was analyzed in detail on a single building scale in the La Punta district. For the rest of Callao region, analysis was performed on a block-unit scale. Our results suggest that approximately 30% of submerged building may be washed away by tsunami inundation in the probabilistic hazard scenario and approximately 60% in the historical hazard scenario.

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TSUNAMI HAZARD AND BUILDING DAMAGE ASSESSMENT IN THAILAND USING NUMERICAL MODEL AND FRAGILITY CURVES

Journal of Earthquake and Tsunami ◽

10.1142/s1793431112500285 ◽

2013 ◽

Vol 07 (05) ◽

pp. 1250028 ◽

Cited By ~ 2

Author(s):

ANAWAT SUPPASRI ◽

FUMIHIKO IMAMURA ◽

SHUNICHI KOSHIMURA

Keyword(s):

Return Period ◽

Fragility Curves ◽

Propagation Model ◽

Tsunami Height ◽

Tsunami Propagation ◽

Inundation Depth ◽

High Resolution Satellite Images ◽

Tsunami Fragility ◽

2004 Tsunami ◽

Inundation Model

Assessing the hazard and damage of a potential tsunami is an ongoing challenge in tsunami research. This study begins by simulating tsunami hazards using historical events. A tsunami propagation model is used to obtain the estimated maximum tsunami height along the west coast of Thailand for a rough return period, and rupture locations that have the potential to generate catastrophic tsunamis in Thailand for a specific return period are proposed. A tsunami inundation model is then performed to quantify each building's maximum inundation depth, using high-resolution satellite images to extract each building's location for the areas of interest located in southern Thailand. Nam Khem village and Patong beach are selected as study areas to represent village communities and tourist attractions, respectively. The model results are then used to obtain the numbers of exposed inhabitants and buildings for each earthquake return period. The developed tsunami fragility curves are applied to these figures to determine the number of potentially damaged buildings. The analysis suggests that the propagation model can be used to obtain rough estimations because it provided results similar to those of the inundation model. However, material type must be considered when fragility curves are used in a different country (i.e. reinforced concrete buildings in Thailand from the 2004 tsunami and wooden houses in Japan from the 2011 East Japan tsunami).

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ANALYSIS OF BUILDING DAMAGE CAUSED BY TSUNAMI AND DEVELOPMENT OF TSUNAMI FRAGILITY CURVES CONSIDERING THE BUILDING AGE

Journal of Japan Society of Civil Engineers Ser B2 (Coastal Engineering) ◽

10.2208/kaigan.76.2_i_709 ◽

2020 ◽

Vol 76 (2) ◽

pp. I_709-I_714

Author(s):

Ryu MIYAMOTO ◽

Anawat SUPPASRI ◽

Fumihiko IMAMURA

Keyword(s):

Fragility Curves ◽

Building Damage ◽

Tsunami Fragility

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Seismically Derived Ground Tilts Related to the 2010 Chilean Tsunami

Seismological Research Letters ◽

10.1785/0220200288 ◽

2021 ◽

Author(s):

Jui-Chun Freya Chen ◽

Wu-Cheng Chi ◽

Chu-Fang Yang

Keyword(s):

Deep Ocean ◽

Propagation Model ◽

Ocean Bottom ◽

Ocean Bottom Seismometer ◽

Tsunami Propagation ◽

Ground Tilt ◽

Tsunami Waves ◽

The Pacific ◽

Seismic Networks ◽

Back Azimuth

Abstract Developing new ways to observe tsunami contributes to tsunami research. Tidal and deep-ocean gauges are typically used for coastal and offshore observations. Recently, tsunami-induced ground tilts offer a new possibility. The ground tilt signal accompanied by 2010 Mw 8.8 Chilean earthquake were observed at a tiltmeter network in Japan. However, tiltmeter stations are usually not as widely installed as broadband seismometers in other countries. Here, we studied broadband seismic records from Japan’s F-net and found ground tilt signals consistent with previously published tiltmeter dataset for this particular tsunamic event. Similar waveforms can also be found in broadband seismic networks in other countries, such as Taiwan, as well as an ocean-bottom seismometer. We documented a consistent time sequence of evolving back-azimuth directions of the tsunami waves at different stages of tsunami propagation through beamforming-frequency–wavenumber analysis and particle-motion analysis; the outcomes are consistent with the tsunami propagation model provided by the Pacific Tsunami Warning Center. These results shown that dense broadband seismic networks can provide a useful complementary dataset, in addition to tiltmeter arrays and other networks, to study or even monitor tsunami propagation using arrayed methods.

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Developing tsunami fragility curves based on the satellite remote sensing and the numerical modeling of the 2004 Indian Ocean tsunami in Thailand

Natural Hazards and Earth System Science ◽

10.5194/nhess-11-173-2011 ◽

2011 ◽

Vol 11 (1) ◽

pp. 173-189 ◽

Cited By ~ 106

Author(s):

A. Suppasri ◽

S. Koshimura ◽

F. Imamura

Keyword(s):

Indian Ocean ◽

Building Materials ◽

Fragility Curves ◽

Distribution Functions ◽

Least Square ◽

Indian Ocean Tsunami ◽

2004 Indian Ocean Tsunami ◽

Inundation Depth ◽

High Resolution Satellite Images ◽

Tsunami Fragility

Abstract. The 2004 Indian Ocean tsunami damaged and destroyed numerous buildings and houses in Thailand. Estimation of tsunami impact to buildings from this event and evaluation of the potential risks are important but still in progress. The tsunami fragility curve is a function used to estimate the structural fragility against tsunami hazards. This study was undertaken to develop fragility curves using visual inspection of high-resolution satellite images (IKONOS) taken before and after tsunami events to classify whether the buildings were destroyed or not based on the remaining roof. Then, a tsunami inundation model is created to reconstruct the tsunami features such as inundation depth, current velocity, and hydrodynamic force of the event. It is assumed that the fragility curves are expressed as normal or lognormal distribution functions and the estimation of the median and log-standard deviation is performed using least square fitting. From the results, the developed fragility curves for different types of building materials (mixed type, reinforced concrete and wood) show consistent performance in damage probability and when compared to the existing curves for other locations.

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Multi-Hazard Resilience Assessment of a Coastal Community Due to Offshore Earthquakes

Journal of Earthquake and Tsunami ◽

10.1142/s1793431119500088 ◽

2019 ◽

Vol 13 (02) ◽

pp. 1950008 ◽

Cited By ~ 2

Author(s):

M. Capozzo ◽

A. Rizzi ◽

G. P. Cimellaro ◽

M. Domaneschi ◽

A. Barbosa ◽

...

Keyword(s):

Cascadia Subduction Zone ◽

Economic Losses ◽

Fragility Functions ◽

Earthquake Intensity ◽

Tsunami Inundation ◽

Ground Failure ◽

Cascading Effects ◽

Innovative Methodology ◽

The Pacific

It has been observed in different parts of the world that offshore earthquakes occurred in coastal regions were followed by tsunamis and catastrophic damages due to cascading effects. In this paper, an innovative methodology for the estimation of direct damage losses and resilience for a given community is presented. It combines two existent methodologies, including both earthquake and tsunami hazards. In detail, fragility functions related to earthquake intensity, ground failure and tsunami inundation are combined with regional hazard data to estimate damages and direct economic losses of buildings and bridges. The coastal city of Seaside in Oregon has been used as a case study and as one of the most vulnerable town in the Pacific North United States due to the proximity of a nearfield Cascadia Subduction Zone. The results indicate that, when the earthquake and the subsequent tsunami inundation are considered together, there is an overwhelming increase in the loss estimates in comparison to the case when the tsunami is separately considered.

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