第２回水災害軽減のための流体力学の活用: 台
風シミュレーション及び被害評価
2nd International workshop on the application of
fluid mechanics to disaster reduction: Cyclone(hurricane/typhoon/extra-tropical) modeling anddamage assessment

March 16-17, 2015
Sendai Civic Auditorium (Shimin Kaikan), Sendai, Japan
Organized by the International Research Institute of Disaster Science (IRIDeS) at
Tohoku University; Funded by IRIDeS and JSPS
Public forum of the 3rd UN World Conference on Disaster Risk Reduction

東北大学は第３回国連防災世界会議を支援しています。

Workshop program and essential information

2nd International Workshop on the Application of Fluid Mechanics to Disaster
Reduction: Cyclone (hurricane/typhoon/extra-tropical) modeling and damage
assessment, March 16-17, 2015, Sendai Civic Auditorium, Sendai, Japan

Monday March 16, 2015
Speaker series and discussion
Location: Sendai Civic Auditorium (Shimin Kaikan), 1st floor, Conference Room #1
Time
9:00-9:10

SpeakerJeremy Bricker

9:10-9:30

Karl Kim

9:30-9:50

Seth Guikema

9:50-10:10

Tori Tomiczek

10:10-10:30 Takuya Miyashita

Affiliation
Tohoku U.

Talk title
Introduction
Learning from Disaster: Co-Benefits of Tsunami, Storm
Surge, and Sea Level Rise Mitigation and Adaptation
University of Hawaii Strategies
Johns Hopkins
University,
Maryland, USA
Hurricanes, Climate Change, and Power System Impacts
University of Notre Hydrodynamic Damage Scheme and Fragility Functions for
Dame, Indiana, USA Hurricane Sandy’s Effects in Coastal New Jersey
Kyoto University,
Hydrodynamic Forces by Tsunami and Storm Surges Acting
Japan
on City Scale Model
AECOM Consulting
Engineers, Utah,
FEMA HAZUS Building Code Losses Avoided – Hurricane
USA
Winds

10:30-10:50 Mathew Francis
10:50-11:00 discussion
11:00-12:00 catered lunch
Nobuhito Mori and Kyoto University,
Modeling of Super Typhoon Haiyan and Related Storm Surge
12:00-12:20 Tomohiro Yasuda Japanand Waves
Hisamichi
Nobuoka and
Ibaragi University, Costal Flood behavior due to Typhoon Haiyan in Hernani
12:20-12:40 Tomohiro Yasuda Japan
based on Field Surveys and Interviews
Tohoku University, Amplification of Destructive Waves by Coral Reef during
12:40-13:00 Volker Roeber
Japan
Typhoon Haiyan, Philippines
Maarten van
Deltares, Delft, The Understanding the mechanisms that led to coastal flooding
13:00-13:20 Ormondt
Netherlands
during Cyclone Haiyan
Tohoku University, Sediment transport due to storm surge and waves during
13:20-13:40 Masashi Watanabe Japan
Typhoon Haiyan in the Philippines
13:40-14:00 discussion
14:00-15:00 break
George Mason
Application of ADCIRC + SWAN to assess geospatial
Seth Lawler and University, Virginia, potential of wetlands to attenuate storm surge damage and
15:00-15:20 Celso FerreraUSAhurricane flooding in the Chesapeake Bay
Dispersion Preserving Numerical Schemes for Coastal Wave
15:20-15:40 Troy Heitmann
University of Hawaii Propagation
Tohoku University, Dam Break Flow Simulation Using Simultaneous Coupling
15:40-16:00 Bagus Adityawan Japan
Method (SCM)
Kyoto University,
Two-way coupled modeling of wave breaking dynamics and16:00-16:20 William Pringle
Japan
inundation under storm waves
University ofMontpellier,
Storm surge modelling from the ocean to the beach during
16:20-16:40 Fabien Retif
Montpellier, France typhoons crossing Taiwan
16:40-17:00 discussion
17:00-18:00 catered dinner
Integration of Coastal Inundation Modeling from Storm Tides
18:00-18:20 Kwok Fai Cheung University of Hawaii to Individual Waves
Ritsumeikan
Simulation of sewage dispersal in Lake Biwa in using a
18:20-18:40 Guillaume Auger University, Japan
particle tracking approach
University of
Bores, Surges and Hydraulic Jumps: from tidal bore field
Queensland,measurements to tsunami-induced bore propagation - can
18:40-19:00 Hubert Chanson Brisbane, Australia we trust hydraulic modelling?
Port and Airport
Research Institute, Consideration of failure mechanism of seawall under storm
19:00-19:20 Taro Arikawa
Japan
surge
19:20-19:30 discussion

2

2nd International Workshop on the Application of Fluid Mechanics to Disaster
Reduction: Cyclone (hurricane/typhoon/extra-tropical) modeling and damage
assessment, March 16-17, 2015, Sendai Civic Auditorium, Sendai, Japan

Location of March 16 workshop: Sendai Civic Auditorium (Shimin Kaikan), 1st floor,
Conference Room #1（仙台市民会館、会議室１）
Seninar location address: 4-1 Sakuragaoka Koen, Aoba-ku, Sendai (仙台市青葉区桜ヶ岡
公園 ４－１)To Sakunami Onsen

Subway Kotodai Koen Station
Jozenji Dori (Street)

Sendai
Civic
Auditorium(ShiminKaikan)Sendai Station

Photo of Sendai
Civic Auditorium

32nd International Workshop on the Application of Fluid Mechanics to Disaster
Reduction: Cyclone (hurricane/typhoon/extra-tropical) modeling and damage
assessment, March 16-17, 2015, Sendai Civic Auditorium, Sendai, Japan

Tuesday March 17, 2015
Study tour of areas rebuilding from tsunami damage in Miyagi PrefectureThis is a joint event with Prof. Kanako Iuchi’s workshop “Recovery after
mega-disasters: people, community, and planning”
Meeting location: 6am at Iwamatsu Ryokan (for guests staying at Iwamatsu), or 6:45am
on HiroseDori in front of the KokubunCho gate
Loc ation
Sakunami Iwamatsu Ryokan
Sendai HiroseDori Kokubuncho Gate
Service area break
Kessennuma
Kessennuma
Nakajima Kaigan
Nakajima Kaigan
Minamisanriku Shizugawa Takano Kaikan
Minamisanriku Sun-Sun Market
Minamisanriku Shizugawa
Onagawa hospital
Onagawa city hall and public housing
Onagawa
Ishinomaki levee construction site
Ishinomaki levee construction site
Sendai Port evacuation tower
Sendai Port evacuation tower
Sendai Station
Sakunami Pizza Restaurant
Sakunami Iwamatsu RyokanTime
6:00 depart
6:45 departbring your own breakfast
10:00 arrive
10:30 depart
11:00 arrive
11:30 depart
12:15 arrive
12:45 lunch at market
13:30 depart
15:00 arrive
15:30 arrive
16:00 depart
16:30 arrive
16:45 depart
17:45 arrive
18:00 depart
19:00 arrive
20:00 arrive
21:00 arrive

Guests staying at Iwamatsu Ryokan will be provided with onigiri (rice balls) for
breakfast.

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2nd International Workshop on the Application of Fluid Mechanics to Disaster
Reduction: Cyclone (hurricane/typhoon/extra-tropical) modeling and damage
assessment, March 16-17, 2015, Sendai Civic Auditorium, Sendai, Japan

Learning from Disaster: Co-Benefits of Tsunami, Storm Surge, and Sea
Level Rise Mitigation and Adaptation Strategies
Karl Kim, Ph.D, Professor of Urban and Regional Planning Executive Director,
National Disaster Preparedness Training Center University of Hawaii
Using data and strategies from Hawaii and other communities impacted or threatenedby natural hazards, this presentation focuses on the co-benefits of an "all-hazards"
approach to coastal disaster risk reduction. In addition to integrating different storm,
tsunami, and flooding models, the research examines different structural andnon-structural approaches to risk reduction. Land use strategies, siting, resilient
building design, as well as other policies for managing coastal hazards are considered.
While early detection and warning systems, as well as evacuation (both vertical andhorizontal) plans and programs are an integral part of increased coastal resilience,
the need to consider longer term strategies for mitigation of hazards and threats is
especially relevant given both the understanding and management of low probability
events as well as uncertainties regarding threats, risks, and vulnerabilities.
Approaching these problems from a holistic, place-based, multi-hazard, andmulti-agent perspective provides the greatest opportunities for risk sharing andcollective management of coastal hazards.

5

2nd International Workshop on the Application of Fluid Mechanics to Disaster
Reduction: Cyclone (hurricane/typhoon/extra-tropical) modeling and damage
assessment, March 16-17, 2015, Sendai Civic Auditorium, Sendai, Japan

Hurricanes, Climate Change, and Power System Impacts
Seth Guikema
Associate Professor
Johns Hopkins University
Department of Geography & Environmental Engineering (primary)Departments of Civil Engineering and Earth & Planetary Science(joint appointments)

ABSTRACT:
Hurricanes regularly impact power systems along the U.S. coast, leading tolarge-scale loss of power. Recent examples include Hurricane Irene with 6-7 million
people without power and Hurricane Sandy with 8-10 million people without power at
the peak outage period. Many of the most vital systems and organizations in the U.S.
are highly dependent on the functioning of the power system. A critical component ofadequately preparing for and responding to these storms is having estimates of themagnitude and spatial distribution of the impacts prior to the event so that electricutilities, other power-dependent utilities, and government agencies can plan
appropriately for their emergency response efforts. This talk summarizes work done
over the past 7 years to develop accurate power outage prediction models
for hurricanes. The current model is an ensemble data mining method trained andvalidated with spatially detailed outage data form over 10 past hurricanes. The
predictive accuracy of the model in past hurricanes has been strong. The talk thenpresents recent work that examines the potential for climate changed inducedchanges in the hurricane environment to lead to changes in risk to power systems
over time. These changes are estimated both in aggregate along the entire US
coastline and more locally at the level of cities and communities.

6

2nd International Workshop on the Application of Fluid Mechanics to Disaster
Reduction: Cyclone (hurricane/typhoon/extra-tropical) modeling and damage
assessment, March 16-17, 2015, Sendai Civic Auditorium, Sendai, Japan7

2nd International Workshop on the Application of Fluid Mechanics to Disaster
Reduction: Cyclone (hurricane/typhoon/extra-tropical) modeling and damage
assessment, March 16-17, 2015, Sendai Civic Auditorium, Sendai, Japan8

2nd International Workshop on the Application of Fluid Mechanics to Disaster
Reduction: Cyclone (hurricane/typhoon/extra-tropical) modeling and damage
assessment, March 16-17, 2015, Sendai Civic Auditorium, Sendai, Japan

Hydrodynamic Forces by Tsunami and Storm Surges Acting on City
Scale Model

Takuya Miyashita1, Nobuhito Mori1*, Tomohiro Yasuda1, Hajime Mase1 and Daniel T. Cox2

1

Disaster Prevention Research Institute, Kyoto University, Japan

2

Oregon State University, USA* mori@oceanwave.jp
Abstract
The 2011 Tohoku Earthquake Tsunami showed complex tsunami behavior along the Japanese
coast. The tsunami propagations in the city were different from rural area and indicatedimportance of hydrodynamic force estimation and locations of buildings, houses and streets.
The fragility of buildings and houses is generally parameterized by water surface elevation andthere is no difference between tsunami and storm surge for application use. However, thehydrodynamic forces between tsunami and storm surge can be different if the intensity issignificantly large.
This study examines physical experiments and numerical simulations to estimate characteristics
of surface elevation and velocity of tsunami and storm surge in a real city condition. The
sensitivity of city structures to surface elevations and velocities is analyzed both tsunami andstorm surge conditions. The city structures shows significant changes of dynamic forces
depends on the locations of buildings and streets.

9

2nd International Workshop on the Application of Fluid Mechanics to Disaster
Reduction: Cyclone (hurricane/typhoon/extra-tropical) modeling and damage
assessment, March 16-17, 2015, Sendai Civic Auditorium, Sendai, Japan

FEMA HAZUS Building Code Losses Avoided – Hurricane Winds
Mathew Francis, AECOM Consulting Engineers, Salt Lake City, Utah, USA
As technical support the need to quantify risk of natural hazards in the US under
Presidential Policy Directive-21, FEMA is performing a national study to modelbuilding code adoption related losses avoided on a parcel level basis. The modelingincludes hurricane wind, flood and seismic hazards, performed on a parcel level basis(level 2 study) in the popular Hazus Multi-Hazard (MH) platform. The pilot study andregional demonstration study of the Southeastern United States involving modeling 17
million buildings is complete, and the national methodology was completed in October
2014.
The presentation will provide an overview of the approach to characterizing modern
International Code Council (I-code) provisions launched in the year 2000, in
comparison to prior building codes used by individual jurisdictions. Details will be
provided for the hurricane wind modeling, assigning varying degrees of damage undervarious loadings for selected Wind Building Characteristics (WBC's) used to modelingstructures in Hazus as reflected in the I-code wind provisions.
The need for orienting building codes to be better aligned with loss drivers and thechallenges with developing histories of adopted wind hazard maps and various buildingcode versions will be explained in context of regional construction practices and legacy
code variations prevalent in the thousands of jurisdictions with hurricane wind exposurein the US. The methodology for managing metadata and geospatial based presentationof results will be illustrated as well as presention of building code benefits in terms of
Average Annualized Losses (AAL) avoided, useful to the insurance industry.
Also included will be a brief overview of planned changes to wind provisions in theAmerican Society of Civil Engineers (ASCE) 7 load standard used in the I-codes, andASCE support for Hurricane Yolanda recovery, as well as other current research by
FEMA, the insurance industry, and the National Institute of Standards and Technology(NIST) under the national wind hazards reduction program.

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2nd International Workshop on the Application of Fluid Mechanics to Disaster
Reduction: Cyclone (hurricane/typhoon/extra-tropical) modeling and damage
assessment, March 16-17, 2015, Sendai Civic Auditorium, Sendai, Japan

Modeling of Super Typhoon Haiyan and Related Storm Surge andWaves

Nobuhito Mori1,*, Tomohiro Yasuda1, Eric Cruz2, Andrew Kennedy3, Sooyoul Kim4, Kenzou
Kumagai5, Yoko Shibutani1, Izuru Takayabu6, Tetsuya Takemi1, Kazuhisa Tsuboki7

1

Disaster Prevention Research Institute, Kyoto University, Japan

2

The University of the Philippines Diliman, Philippines

3

The University of Notre Dame, USA

4

Tottori University, Japan

5

Pacific Consultants, Japan

6

Metrological Research Institute, Japan

7

Hydrospheric Atmospheric Research Center, Nagoya University, Japan* mori@oceanwave.jp
Abstract
Typhoon Haiyan, which struck the Philippines in November 2013, was an extremely intense
tropical cyclone that had a catastrophic impact. The minimum central pressure of Typhoon
Haiyan was 895 hPa, making it the strongest typhoon to make landfall on a major island in thewestern North Pacific Ocean. Characteristics of Typhoon Haiyan and its related storm surge are
estimated by numerical experiments using numerical weather prediction models and a storm
surge model. A series of Typhoon dynamic downscaling by WRF, CReSS and MRI-NHM andempirical modeling was conducted to predict and hindcast of Typhoon Haiyan and related storm
surge and wind waves.
Based on the analysis of best hindcast results, the storm surge level was 5-6 m and local
amplification of water surface elevation due to seiche was found to be significant inside Leyte
Gulf. The numerical experiments show the coherent structure of the storm surge profile due tothe specific bathymetry of Leyte Gulf and the Philippines Trench as a major contributor to thedisaster in Tacloban. The numerical results also indicated the sensitivity of storm surge forecast.
Effects of global warming is examined based on pseudo-global warming experiments
considering sea surface temperature increase. The results will be presented at the conference.

11

2nd International Workshop on the Application of Fluid Mechanics to Disaster
Reduction: Cyclone (hurricane/typhoon/extra-tropical) modeling and damage
assessment, March 16-17, 2015, Sendai Civic Auditorium, Sendai, Japan

Costal Flood behavior due to Typhoon Haiyan in Hernani based on
Field Surveys and Interviews
Hisamichi NOBUOKA*1, Tomohiro YASUDA*2, Yoshimitsu TAJIMA*3*1 Department of Urban and Civil Engineering, Ibaraki University, Japannobuoka@mx.ibaraki.ac.jp*2 Disaster Prevention Research Institute, Kyoto University, Japan*3 Department of Civil Engineering, The University of Tokyo, JapanThe movie presented by Plan International NGO in Hernani showed us heavy
impact of coastal flood due to Typhoon Haiyan on 8th November 2013. This
presentation is a part of the survey's results by the special team of Japan Societyof Civil Engineers, in December 2013 and January 2014, to understand the movie
and this flood scientifically.
Water levels of the coastal flood according to witness of residents were
measured in two Barangays with interviews on the flood behaviors. The point where
the movie was taken was specified with measurements of some length of houses those
appeared in the movie. One police man told the detail phenomena in Hernani fromthe previous evening to the time of flood, who had been in police station at thefirst floor of the town hall close to a beach of sea. These results confirm us
the behavior of the coastal flood in Hernani.

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2nd International Workshop on the Application of Fluid Mechanics to Disaster
Reduction: Cyclone (hurricane/typhoon/extra-tropical) modeling and damage
assessment, March 16-17, 2015, Sendai Civic Auditorium, Sendai, Japan

Amplification of Destructive Waves by Coral Reef during
Typhoon Haiyan in the Philippines
Volker Roeber and Jeremy D. Bricker
International Research Institute of Disaster Science, Tohoku University, Sendai, Japan
Many coastal communities are at constant risk from typhoons and storm surges. Though coastal
resilience has generally improved over the past decades throughout more accurate and detailed
storm forecast systems and coastal defenses, some dangerous wave phenomena are notaccounted for in hazard assessment and evacuation plans.
Typhoon Haiyan, which struck the Philippines in November 2013, revealed such a situation
where a tsunami-like bore destroyed the village of Hernani in Eastern Samar. The destructive
waves came at surprise to many villagers and researchers as the coast near Hernani is shelteredby a shallow and broad fringing reef with steep bathymetry offshore. The lack of a shallow
continental shelf prevented the generation of wind-driven storm surge and the coral reef was
expected to serve as an efficient protection from swell waves.
However, under the extreme storm conditions of Typhoon Haiyan individual waves overtopped
the reef and the release of bound infra-gravity waves during wave breaking in turn favoredstrong surf beat amplification over the reef. Superposition of incoming wave groups with theoscillating water body nearshore caused tsunami-like surges of much longer period than regularswell waves that were responsible for the destruction of the village and its coastal defense
structures.
We have replicated the local bathymetry and topography based on data gathered during a fieldsurvey. We have computed the wave conditions during the peak of the typhoon with theBoussinesq-type model, BOSZ, and the RANS-type model, OpenFOAM. Both models show thesurf beat is strongly dependent on the local reef dimensions. The incoming swell waves
nonlinearly interact with the resonating water body and lead to local exacerbation of both flow
depth and flow speed compared to hypothetical scenarios without any fringing reef.
We will discuss the model results and provide further insight into the mechanisms that are
responsible for such kind of counter-intuitive natural phenomenon.

13

2nd International Workshop on the Application of Fluid Mechanics to Disaster
Reduction: Cyclone (hurricane/typhoon/extra-tropical) modeling and damage
assessment, March 16-17, 2015, Sendai Civic Auditorium, Sendai, Japan

Understanding the mechanisms that led to coastal flooding
during Cyclone Haiyan
Maarten van Ormondt (Deltares, Unesco-IHE) and Dano Roelvink (Deltares, Unesco-IHE)

Cyclone Haiyan left a trail of widespread destruction after it hit the Philippines on
November 8, 2013. It was the strongest storm ever recorded at landfall, and thedeadliest Philippine cyclone on record, killing at least 6,300 people in that country
alone. Most fatalities occurred as a result of coastal flooding. The physical mechanismsthat led to this flooding varied widely from place to place. Tacloban City appears tohave been hit by a ‘classic’ storm surge, with strong southerly and easterly winds
pushing waters up into the shallow San Pedro and San Pablo Bay. The town of Basey,at the northern shore of the bay, first saw the water in the bay receding as a result ofstrong offshore-directed winds, after which it was hit by a series of a tsunami-likewaves. On the open coast in the province of Eastern Samar, the continental shelf isnarrow, which strongly limits the development of a storm surge. In this area, many
towns were destroyed by what appears to have been (infragravity) wave run-up.
Here, we present the results of our hydrodynamic modeling study in which we attempt
to quantify the contribution of the various mechanisms (such as wind set-up, wind
set-down, wave set-up, infragravity wave run-up) that caused the coastal flooding. For
this purpose, a cascade of different nested hydrodynamic models was set up, ranging
from regional coupled Delft3D-SWAN models to high-resolution XBeach models along
the open coast of Eastern Samar, that are used to compute the infragravity wave
run-up.

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2nd International Workshop on the Application of Fluid Mechanics to Disaster
Reduction: Cyclone (hurricane/typhoon/extra-tropical) modeling and damage
assessment, March 16-17, 2015, Sendai Civic Auditorium, Sendai, Japan
Sediment transport due to storm surge and waves during Typhoon Haiyan in thePhilippines
Masashi Watanabe1*, Jeremy D. Bricker2, Kazuhisa Goto2, Fumihiko Imamura2
1

School of Engineering, Tohoku University

2

International Research Institute of Disaster Science (IRIDeS), Tohoku University* watanabe@tsunami2.civil.tohoku.ac.jp
A geological field survey in the Philippines after Typhoon Haiyan showed that the inland extent
of sand transported by the storm surge was smaller than during the 2011 Tohoku-oki tsunami. In
Tanauan in Leyte Gulf, the inland limit of the sand deposit extended 0.2km from the shoreline,
while inundation extended 2.6km from the shoreline. On the other hand, the inland limit of sanddeposit after the 2011 Tohoku-oki tsunami extended 4.3 km from the shoreline, while
inundation extended 5.0 km from the shoreline. Therefore, in this study, we used a numericalmodel to determine why the extent of sand deposition during the typhoon was much less thanthe extent of inundation, while during the tsunami the extent of sand deposition was only
slightly less than the extent of inundation.
We used Delft-3D and SWAN to calculate the pressure-, wind-, and breaking-wave-induced
storm surges, wave field, and sediment transport during Typhoon Haiyan. The computed bed
shear stress was large near shoreline and decreased inland. Therefore, sand dunes near the
shoreline were eroded, transported inland, and deposited within 0.2 km inland of the shoreline.
When we carried out simulations without waves, deposited sediment thickness was muchsmaller than field survey results, bed shear stress was small even near shoreline, anderosion/sedimentation was generated where a sand layer was not observed. From these results,
we revealed that waves were responsible for eroding the sand dunes near the shoreline. Since
waves did not penetrate far inland, neither did the sand deposit. Therefore, sand was transported
only up to 0.2 km inland from the shoreline.

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2nd International Workshop on the Application of Fluid Mechanics to Disaster
Reduction: Cyclone (hurricane/typhoon/extra-tropical) modeling and damage
assessment, March 16-17, 2015, Sendai Civic Auditorium, Sendai, Japan

Application of ADCIRC + SWAN to assess geospatial potential of wetlands toattenuate storm surge damage and hurricane flooding in the Chesapeake Bay
Seth Lawler1, Jana Haddad2, Mithun Deb1, Juan Garzon1, Celso Ferreira3
1

Graduate Student, Department of Civil, Infrastructure and Environmental Engineering,
George Mason University.
2
Undergraduate Student, Department of Civil, Infrastructure and Environmental
Engineering, George Mason University.
3
Assistant Professor, Department of Civil, Infrastructure and Environmental
Engineering, George Mason University.
Storm surge resulting from tropical and extra-tropical storms is a perennial threat toinfrastructure along the coastal areas of the mid-Atlantic region and the Chesapeake Bay
in the United States. It is believed that coastal wetlands act as a natural buffer,attenuating the devastating consequences of storm surge and mitigating the impact toinfrastructure that are protected by these areas. Laboratory studies have been conducted
relating the frictional resistance of vegetation typical to wetlands of the mid-Atlantic
region, however few field studies exist to corroborate experimental results or apply
appropriate spatial scaling. To improve knowledge in the area of flow resistance throughwetland ecosystems in storm conditions, we have modeled surge in the Chesapeake Baywith the coupled hydrodynamic-wave model (ADCIRC+SWAN) using a combination ofsynthetic storms and hindcasts of historical storms that have affected the region.
Following model validation using historical records, we conducted a sensitivity analysis
of friction parameterization and spatial scaling to improve calibration of this model inwetland areas. Results from modelling are then compared with water level datacollected over the past year in a parallel field study conducted in protected wetlands(included in the model at 10m resolution) of the Chesapeake Bay. Geospatial andstatistical analyses were then carried out to develop a relationship between wetland land
cover and hurricane flooding to produce a spatial perspective on the potential for
wetlands to attenuate storm surge. Results from this study will improve the ability ofdecision makers to evaluate the benefits of wetlands from a flooding and storm-surge
attenuation perspective.

16

2nd International Workshop on the Application of Fluid Mechanics to Disaster
Reduction: Cyclone (hurricane/typhoon/extra-tropical) modeling and damage
assessment, March 16-17, 2015, Sendai Civic Auditorium, Sendai, Japan

Dispersion Preserving Numerical Schemes for Coastal Wave
Propagation
Troy Heitmann*, Yefei Bai, Kwok Fai Cheung
Department of Ocean and Resources Engineering
University of Hawaii at Manoa, Honolulu, Hawaii 96822, USA
troyheit@hawaii.edu, yefei@hawaii.edu, cheung@hawaii.edu
Volker Roeber
International Research Institute of Disaster Science
Tohoku University, Sendai 980-8579, Japanroeber@irides.tohoku.ac.jp
The severity of coastal inundation, resulting from tsunami runup and storm surge events,
continues to threaten coastal communities throughout the world. Researchers continue todevelop and improve numerical models capable of refining our knowledge and improving ourunderstanding of the underlying physics. The ever increasing availability of computational
resources has further permitted the use of high fidelity phase-resolving models for practicalapplications. Boussinesq-type models, for example, serve as an indispensable tool in the studyof wave dynamics affiliated with inundation studies [1].
Numerical challenges arising from the discretization of Boussinesq-type equations are mostapparent in resolving surf zone processes, where wave breaking and runup processes are
depicted as discontinuous. Numerical methods used to overcome discontinuous obstacles areoften dissipative and/or dispersive in order to preserve numerical stability. Recently, theapplication of shock capturing conservative numerical methods to these processes has led torobust and accurate solutions [2]. Beyond the surf zone, theoretical advances in Boussinesq-type
equations continue to push computational boundaries further offshore to better resolve bothlinear and nonlinear transformation throughout intermediate depths. However, if the same
numerical methods utilized in a discontinuous region are applied over an extensive
computational area, wave propagation characteristics are hindered, leading to false positive
assessments of the wave dynamics at the surf zone boundary.
The dispersion relation preserving scheme of [3] emphasizes wave propagation in thediscretization of the governing equations by minimizing the error associated with numericaldispersion over a given range of frequencies and wavenumbers, such that the phase is accurately
represented in the solution. Its implementation in water wave models represents an important
advancement in coastal engineering research. We present a numerical model that implements
this discretization scheme to the Boussinesq-type numerical model BOSZ [2]. As a net result,both linear and nonlinear processes are resolved with improved accuracy leading to an enhanced
understanding of coastal processes.
References:[1] Li, N., Roeber, V., Yamazaki, Y., Heitmann, T., Bai, Y., Cheung, K.F., 2014. Integration of
Coastal Inundation Modeling from Storm Tides to Individual Waves. Ocean Modeling, 83,
26-42.
[2] Roeber, V., Cheung, K.F., 2012. Boussinesq-type Model for Energetic Breaking Waves in
Fringing Reef Environments. Coastal Engineering, 70(1), 1-20.
[3] C.K.W. Tam, J.C. Webb, (1993). Dispersion-relation-preserving Finite Difference Schemes
for Computational Acoustics, Journal of Computational Physics, 107, 262.
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2nd International Workshop on the Application of Fluid Mechanics to Disaster
Reduction: Cyclone (hurricane/typhoon/extra-tropical) modeling and damage
assessment, March 16-17, 2015, Sendai Civic Auditorium, Sendai, Japan

Dam Break Flow Simulation Using Simultaneous Coupling Method(SCM)

Mohammad Bagus Adityawan*
Hitoshi Tanaka*
Yuta Mitobe**

Department of Civil Engineering, Tohoku University, Aobayama, Aoba-ku, Sendai 980-8576,
Japan

This study presents numerical simulation of dam break induced flows using Simultaneous
Coupling Method (SCM). SCM is based on shallow water equations (SWE) coupled with k-model that estimates bed stress from the boundary layer. SWE is solved using finite volumescheme that is able to handle shock and discontinuity. The calculated depth averaged velocity
from SWE is assumed as the free stream velocity and used to estimate bed stress directly fromthe boundary layer. Therefore, SCM has the benefits of a more accurate bed stress assessment
than the conventional method (i.e. Manning). The results from the simulation is compared andverified with measurement data. The method is able to produce known behavior of bed stressunder unsteady flow. SCM is a valuable tool in assessing bed stress induced damages in water
related disasters.

18

2nd International Workshop on the Application of Fluid Mechanics to Disaster
Reduction: Cyclone (hurricane/typhoon/extra-tropical) modeling and damage
assessment, March 16-17, 2015, Sendai Civic Auditorium, Sendai, Japan

19

2nd International Workshop on the Application of Fluid Mechanics to Disaster
Reduction: Cyclone (hurricane/typhoon/extra-tropical) modeling and damage
assessment, March 16-17, 2015, Sendai Civic Auditorium, Sendai, Japan

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2nd International Workshop on the Application of Fluid Mechanics to Disaster
Reduction: Cyclone (hurricane/typhoon/extra-tropical) modeling and damage
assessment, March 16-17, 2015, Sendai Civic Auditorium, Sendai, Japan

Integration of Coastal Inundation Modeling from Storm Tides
to Individual Waves
Ning Li1, Volker Roeber2, Yoshiki Yamazaki1, Troy W. Heitmann1, Yefei Bai1, andKwok Fai Cheung1
1

Department of Ocean and Resources Engineering, University of Hawaii at Manoa,
Honolulu, Hawaii 96822, USA
2International Research Institute of Disaster Science, Tohoku University, Sendai
980-8579, Japan
ABSTRACT
Modeling of storm-induced coastal inundation has primarily focused on the surge
generated by atmospheric pressure and surface winds with phase-averaged effects of the
waves as setup. Through an interoperable model package, we investigate the role ofphase-resolving wave processes in simulation of coastal flood hazards. A spectral ocean
wave model describes generation and propagation of storm waves from deep tointermediate water, while a non-hydrostatic storm-tide model has the option to couple
with a spectral coastal wave model for computation of phase-averaged processes in anear-shore region. The ocean wave and storm-tide models can alternatively provide thewave spectrum and the surface elevation as the boundary and initial conditions for anested Boussinesq model. Additional surface-gradient terms in the Boussinesq
equations maintain the quasi-steady, non-uniform storm tide for modeling ofphase-resolving surf and swash-zone processes as well as combined tide, surge, andwave inundation. The two nesting schemes are demonstrated through a case study of
Hurricane Iniki, which made landfall on the Hawaiian Island of Kauai in 1992. With
input from a parametric hurricane model and global reanalysis and tidal datasets, thetwo approaches produce comparable significant wave heights and phase-averaged
surface elevations in the surf zone for comparison. The nesting of the Boussinesq model
provides a seamless approach to augment the inundation due to the individual waves inmatching the recorded debris line along the coast.

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2nd International Workshop on the Application of Fluid Mechanics to Disaster
Reduction: Cyclone (hurricane/typhoon/extra-tropical) modeling and damage
assessment, March 16-17, 2015, Sendai Civic Auditorium, Sendai, Japan

22

2nd International Workshop on the Application of Fluid Mechanics to Disaster
Reduction: Cyclone (hurricane/typhoon/extra-tropical) modeling and damage
assessment, March 16-17, 2015, Sendai Civic Auditorium, Sendai, Japan

23

2nd International Workshop on the Application of Fluid Mechanics to Disaster
Reduction: Cyclone (hurricane/typhoon/extra-tropical) modeling and damage
assessment, March 16-17, 2015, Sendai Civic Auditorium, Sendai, Japan

24

2nd International Workshop on the Application of Fluid Mechanics to Disaster
Reduction: Cyclone (hurricane/typhoon/extra-tropical) modeling and damage
assessment, March 16-17, 2015, Sendai Civic Auditorium, Sendai, Japan

Consideration of failure mechanism of seawall under storm surge
Taro Arikawa
Port and Airport Research Institute, Yokosuka, Japan
Seawalls play an important role to prevent the high tide by storm surge. These seawalls
were often destroyed by combination of high tides and high waves. For example, astorm surge by the typhoon in 2004 destroyed seawalls in the Seto Island Sea. 13
seawalls were destroyed, of which 10 were the leaning revetment type. But failure
mechanism of seawall under the storm surge condition has not yet been determined.
In this study, at first, physical experiments were conducted to inspect destruction form
by using the leaning revetments as an example, and processes of leaning revetments andits factors in putting emphasis behaviors of revetment’s bodies. Then, the effect on theinundation of high tide due to failures of seawalls were verified by using the numericalsimulations. The results of the experiments confirmed that blocks touching the bottomof revetments had an effect of retarding sharp sliding, and destruction of the joint mightoccur if impulsive wave force acted on revetments in particular conditions. The
resiliency of the seawalls against storm surge was considered through numerical results.

25

2nd International Workshop on the Application of Fluid Mechanics to Disaster
Reduction: Cyclone (hurricane/typhoon/extra-tropical) modeling and damage
assessment, March 16-17, 2015, Sendai Civic Auditorium, Sendai, Japan

Transportation being arranged
In order to get all workshop attendees from place to place, we are arranging charterbuses. The charter bus schedule will be as follows:
March 15
9:00 pm Leave Sendai Station east exit (meet on pedestrian deck just outside 2nd floor
east exit bridge)
10:00 pm Arrive Iwamatsu Ryokan and meet to plan March 16 workshops.
March 16
7:45 am Leave Iwamatsu Ryokan
8:30 am Arrive Sendai Civic Auditorium (Prof. Bricker’s workshop)
8:45 am Arrive Kawauchi B bldg. (Prof. Iuchi’s workshop)
7:45 pm Leave Sendai Civic Auditorium (Prof. Bricker’s workshop)
8:00 pm Leave Kawauchi B bldg. (Prof. Iuchi’s workshop)
8:45 pm Arrive Iwamatsu Ryokan and meet to summarize workshop conclusions.
March 17 All-day bus tour (detail above)
Night meeting at Iwamatsu Ryokan to summarize lessons learned from tsunami
recovery study tour.
March 18
10:00 am Leave Iwamatsu Ryokan
11:00 am Arrive Sendai Station
If you decide to arrive and leave at times not convenient to this charter bus schedule,
please take public transportation to Iwamatsu Ryokan and/or Sendai Civic Auditorium.
Public transit information is given in detail on the following pages.

Photo of Iwamatsu Ryokan
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2nd International Workshop on the Application of Fluid Mechanics to Disaster
Reduction: Cyclone (hurricane/typhoon/extra-tropical) modeling and damage
assessment, March 16-17, 2015, Sendai Civic Auditorium, Sendai, Japan

How to get to the hotel from Sakunami Station (if you don’t take the charter bus)
Iwamatsu Ryokan (hotel) in Sakunami Onsen 岩松旅館（作並温泉）
Address: Motoki-16 Sakunami, Aoba Ward, Sendai,989-3431 宮城県仙台市青葉区作並元木 16
Phone: 022-395-2211

Iwamatsu Ryokan

岩松旅館

North

JR Senzan Line, Sakunami Station
JR 仙山線、作並駅

From Sakunami Station (作並駅), take the free shuttle bus to Iwamatsu Ryokan (about a
5 minute drive). Often there are shuttles in front of the station for many different
hotels, so make sure you take the one marked Iwamatsu Ryokan (岩松旅館). If there
is a problem, ask the station agent to phone the hotel at 022-395-2211, or phone
Jeremy’s cell at 080-9628-9902. From a non-Japanese phone, you can call Jeremy bydialing +81-80-9628-9902.

27

2nd International Workshop on the Application of Fluid Mechanics to Disaster
Reduction: Cyclone (hurricane/typhoon/extra-tropical) modeling and damage
assessment, March 16-17, 2015, Sendai Civic Auditorium, Sendai, Japan

How to get to Sakunami Station from Sendai Station (if you don’t take the charterbus)
Senzan line trains usually leave Sendai station from Platform 7 or Platform 8. However,other lines use these platforms too, so make sure the train says Senzan line (仙山線), orthat it's heading to either Yamagata（山形）or Sakunami (作並).
Sunday schedule
Sendai station Sakunami station
6:10
6:51
7:07
7:50
8:15
8:53
9:04
9:41
10:07
10:47
11:18
11:56
12:11
12:54
13:01
13:38
14:04
14:36
15:00
15:39
16:01
16:34
17:00
17:37
17:47
18:29
18:27
19:09
18:47
19:29
19:38
20:18
20:27
21:04
21:04
21:43
22:16
22:54

On all days, the last train to Sakunami leaves Sendai station at 22:16!
On all days, the first train to Sendai station leaves Sakunami at 6:19, and arrives Sendai
station at 6:49.
The fare for a 1-way trip between Sendai station and Sakunami station is 496 yen.

28

2nd International Workshop on the Application of Fluid Mechanics to Disaster
Reduction: Cyclone (hurricane/typhoon/extra-tropical) modeling and damage
assessment, March 16-17, 2015, Sendai Civic Auditorium, Sendai, Japan

How to get to Sendai Station from overseas
The easiest way to get to Sendai is to fly from wherever you are coming from to Sendai
Airport. From Sendai Airport, take the Airport Access Line to Sendai Station. The
one-way fare is 650 yen, and the full timetable is available in English and Japanese at
http://www.senat.co.jp/20140315_timetable.pdf
If arriving at Sendai Airport by airplane, make sure to arrive in time to catch the 21:32
Airport Access Line train, which arrives at Sendai Station at 21:56, plenty of time tocatch the last Senzan Line train to Sakunami at 22:16.
Another way to get to Sendai Station is by bullet train (Shinkansen). From Narita
Airport, go to the JR rail counter, and buy a ticket all the way to Sendai station. The
first part of this trip will be either a Limited Express train called the Narita Express(NEX) or a Rapid Service (Kaisoku) to Tokyo Station (about a 1 hour ride). At Tokyo
Station, you will follow transfer signs for the Tohoku Shinkansen (the green Shinkansensign). The Tohoku Shinkansen will come all the way to Sendai Station (a 1.5 to 2 hourride, depending on the train). The 1-way rail fare from Narita Airport to Sendai station
is approximately 13,000 yen. Timetables for these trains are available in English at
http://www.jreast.co.jp/e/timetables/index.html
Make sure you get to Sendai Station in time to catch the last Senzan Line train to
Sakunami at 22:16.

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2nd International Workshop on the Application of Fluid Mechanics to Disaster
Reduction: Cyclone (hurricane/typhoon/extra-tropical) modeling and damage
assessment, March 16-17, 2015, Sendai Civic Auditorium, Sendai, Japan

Emergency Contact Information
Jeremy Bricker
Phone: +81-80-9628-9902 from a foreign phone, or 080-9628-9902 from a Japanesephone.
Email: bricker [at] irides.tohoku.ac.jp
Volker Roeber
Phone: +81-80-9628-2360 from a foreign phone, or 080-9628-2360 from a Japanesephone.
Email: roeber [at] irides.tohoku.ac.jp
Workshop homepage:
http://hydraulic.lab.irides.tohoku.ac.jp/app-def/S-102/2014/?page_id=26830