記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Springer Science and Business Media LLC  

Abstract

The 2022 Hunga Tonga-Hunga Ha’apai eruption generated tsunamis that propagated across the Pacific Ocean. Along the coast of Japan, nearshore amplification led to amplitudes of nearly 1 m at some locations, with varying peak tsunami occurrence times. The leading tsunami wave can generally be reproduced by Lamb waves, which are a type of air-pressure wave generated by an eruption. However, subsequent tsunamis that occurred several hours after the leading wave tended to be larger for unknown reasons. This study performs multi-scale numerical simulations to investigate subsequent tsunami waves in the vicinity of Japan induced by air pressure waves caused by the eruption. The atmospheric pressure field was created using a dispersion relation of atmospheric gravity wave and tuned by physical parameters based on observational records. The tsunami simulations used the adaptive mesh refinement method, incorporating detailed bathymetry and topography to solve the tsunami at various spatial scales. The simulations effectively reproduced the tsunami waveforms observed at numerous coastal locations, and results indicate that the factors contributing to the maximum tsunami amplitude differ by region. In particular, bay resonance plays a major role in determining the maximum amplitude at many sites along the east coast of Japan. However, large tsunami amplification at some west coast locations was not replicated, probably because it was caused by amplification during oceanic wave propagation rather than meteorological factors. These findings enhance our understanding of meteotsunami complexity and help distinguish tsunami amplification factors.

DOI： 10.1007/s00024-023-03332-9

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その他リンク： https://link.springer.com/article/10.1007/s00024-023-03332-9/fulltext.html

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s00477-023-02379-3

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担当区分：責任著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2208/kaigan.78.2_i_283

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担当区分：筆頭著者,　責任著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2208/kaigan.78.2_i_331

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2208/kaigan.78.2_i_397

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担当区分：筆頭著者,　責任著者   記述言語：日本語   出版者・発行元：公益社団法人 土木学会  

近年，設計沖波の見直しが全国的に進んでおり，これに伴って設計波が大きくなると推測されることから，今後，消波工の需要は高まっていくと考えられる．現在，設計時に護岸の越波量を推測する場合，条件が合わなくても合田の越波流量算定図を使うほかない．松下らにより実施工事例に対応した波浪条件や被覆条件での越波流量算定図の提案が行われたが，勾配1/30の緩勾配海岸での結果であり，我が国には海底勾配1/10程度の海岸も多くあることから，急勾配海岸での検証も必要である．本研究では急勾配海岸において，護岸と消波工の天端高が同じ完全被覆かつ全断面被覆形式での越波流量算定図の作成を目指して，水理模型実験を実施した．合田算定図と比較するとともに，海底勾配の影響について考察した．さらに，打上げ・越波統合算定モデル（IFORM）の消波護岸における適用性について検討した．

DOI： 10.2208/jscejoe.78.2_i_451

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掲載種別：研究論文（学術雑誌）   出版者・発行元：American Society of Civil Engineers (ASCE)  

DOI： 10.1061/(asce)ww.1943-5460.0000690

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掲載種別：研究論文（学術雑誌）  

DOI： 10.2208/kaigan.77.2_i_181

J-GLOBAL

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掲載種別：研究論文（学術雑誌）  

DOI： 10.2208/kaigan.77.1_1

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担当区分：責任著者   掲載種別：研究論文（学術雑誌）  

DOI： 10.2208/kaigan.77.2_i_151

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担当区分：筆頭著者,　責任著者   掲載種別：研究論文（学術雑誌）  

DOI： 10.2208/kaigan.77.2_i_67

J-GLOBAL

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担当区分：責任著者   掲載種別：研究論文（学術雑誌）  

DOI： 10.2208/kaigan.77.2_i_13

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掲載種別：研究論文（学術雑誌）  

DOI： 10.2208/kaigan.77.2_i_331

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掲載種別：研究論文（学術雑誌）  

DOI： 10.2208/kaigan.77.2_i_211

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担当区分：筆頭著者,　責任著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2208/kaigan.77.2_i_919

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担当区分：責任著者   記述言語：日本語   出版者・発行元：公益社団法人 土木学会  

災害時の避難行動において避難を阻害する要因の一つに認知的不協和が挙げられる．本研究では，平成30年台風第21号高潮災害時の避難行動に関するアンケート調査を実施し，得られたデータを用いて認知的不協和が避難行動に与える影響を明らかにすることを目的とする．アンケート調査結果から，自宅が浸水する可能性があると認知していたにもかかわらず，実際に避難した人は少なく，認知的不協和が発生していた可能性が示された．さらに，避難行動選択に関するロジットモデルを構築し，認知的不協和が避難行動に与える影響の定量分析を行った．分析により推定されたパラメータの値から，人々は死亡確率または災害発生確率を不当に低く見積もっていたことがわかった．したがって，実際の高潮災害時に認知的不協和が発生していたことが明らかになった．

DOI： 10.2208/kaigan.77.2_i_1057

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担当区分：筆頭著者,　責任著者   記述言語：英語   出版者・発行元：富士技術出版株式会社  

<p>The detailed understanding of tsunami hazard risk using numerical simulations requires a numerical model that can accurately predict tsunami inundation phenomena on land. In such models, the structural effects are indirectly considered using the variation of bottom roughness as a proxy for the differences in building densities. Only a few studies have conducted intermodel tests to investigate tsunami inundation in complex coastal urban cities. During the tsunami analysis hackathon held in September 2020, eight research groups met to have a detailed discussion on the current urban inundation problems. In this study, we conducted an intermodel comparison of the numerical tsunami models, using the data from physical experiments that were performed on a detailed urban model. Our objective was to investigate the necessary conditions of an accurate numerical model based that can ensure high reproducibility and practicality. It was confirmed that the accuracy of topographic data is an important parameter for tsunami inundation simulations in complex urban areas. Based on the computational cost and accuracy, we suggest that a resolution of 1 cm of topographic data is a sufficient condition for tsunami inundation simulations on 1/250 scale model.</p>

DOI： 10.20965/jdr.2021.p0978

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2208/jscejoe.77.2_i_55

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記述言語：日本語   出版者・発行元：公益社団法人 土木学会  

東北地方太平洋沖地震後，防潮堤への信頼や安心感という防災施設に対する住民の認識や過信が，津波からの避難意思決定に影響を与えた可能性についての指摘があった．本研究では，南海トラフ巨大地震に備えた防潮堤整備が進む静岡県浜松市沿岸域における住民を対象として実施したアンケート調査データを用いて，防災教育の受講有無によるクロス集計を行った．さらに，構造方程式モデリング（共分散構造分析）により防潮堤に対する認識を考慮した住民の避難意思決定プロセスを分析した．その結果，防災教育受講の有無による避難決定メカニズムの違いをみることで，防災教育が避難を促すいくつかのルートの中で最も有効的なルートは，防災への関心や理解を直接高めるルートであることが示された．

DOI： 10.2208/jscejipm.76.5_i_141

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その他リンク： https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-18K18563/

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掲載種別：研究論文（学術雑誌）  

DOI： 10.2208/kaigan.77.1_18

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掲載種別：研究論文（学術雑誌）  

DOI： 10.2208/kaigan.77.2_i_1105

J-GLOBAL

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：公益社団法人 土木学会  

本研究では，従来より国内で広く用いられてきたロジックツリーアプローチを用いた確率論的津波ハザード評価手法のうち，主として地震断層の滑り分布の設定手法，および，偶然的不確定性の考え方を刷新することで，より説明力の高い確率論的津波ハザード評価手法であるcoRaL法(a method of incorporating Random phase model into Logic tree approach)を提案することを目的とする．南海トラフ巨大地震による津波襲来のリスクが想定されている太平洋沿岸に位置する都市を対象として提案手法を適用し，確率規模毎（150年，500年，1000年，2500年等）の津波浸水深分布や，同一の確率規模でも，津波ハザード評価の不確定性を考慮したパーセンタイル毎の津波浸水深分布を評価可能であることを示す．

DOI： 10.2208/kaigan.77.2_i_175

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J-GLOBAL

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掲載種別：研究論文（学術雑誌）   出版者・発行元：Coastal Engineering Research Council  

This coastal hazards emphasize the need for engineers to understand the fundamental processes causing damage and the potential of maximum damage in order to design coastal communities with increased resilience to tsunami events. Common methods used to evaluate local conditions caused by tsunamis include post-disaster reconnaissance field surveys, numerical modelling, and laboratory experiments. Behavior of land side tsunami, inundation, is not well known as well as the fluid forcing, fragility characteristics and accuracy of tsunami hazard mapping. This study targets to understand local tsunami behavior in a city scale including complex buildings and improve modelling of tsunami inundation in an urban area. Laboratory experiments are an essential starting point in the investigation of urban roughness effects on wave propagation and maximum pressures in coastal communities. Physical modelling usually uses solitary wave, bore wave, and wave imitating Nankai Trough Earthquake as a tsunami wave.Recorded Presentation from the vICCE (YouTube Link): https://youtu.be/-4niVrzXviE

DOI： 10.9753/icce.v36v.currents.14

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掲載種別：研究論文（学術雑誌）  

DOI： 10.2208/kaigan.76.2_i_313

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掲載種別：研究論文（学術雑誌）  

DOI： 10.2208/kaigan.76.2_i_373

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

J-GLOBAL

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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掲載種別：研究論文（学術雑誌）   出版者・発行元：Elsevier {BV}  

DOI： 10.1016/j.sandf.2019.08.008

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掲載種別：研究論文（学術雑誌）  

© 2019 Japan Society of Civil Engineers. Typhoon Jebi in 2018 caused severe damage along areas of Osaka Bay, Japan. After the storm, a Japan Society of Civil Engineers (JSCE) coastal survey group surveyed the coastal impacts and recorded watermarks inside Osaka Bay and along the Pacific. The maximum storm tide recorded by a tide gauge was 3.29 m at the Osaka Tide Station, which is a historical high for Osaka Bay. Coastal flooding consisted of both storm surge and wave run-up in almost all locations, with flooding exceeding 5 m and 12 m in elevation from mean sea level in the inner parts of Osaka Bay and along the Pacific coast, respectively. Coastal damage was severe in areas located outside of coastal barriers, such as ports and harbors, while residential areas were mainly well protected and spared due to coastal protection systems. In addition, some inland flooding occurred in the Kobe-Ashiya regions due to the storm surge propagating up several small rivers. This survey report summarizes the findings of the post-event survey by JSCE and analyzes the relation between maximum water level and resulting damage.

DOI： 10.1080/21664250.2019.1619253

Scopus

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.3389/fbuil.2019.00046

Web of Science

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掲載種別：研究論文（学術雑誌）   出版者・発行元：Japan Society of Civil Engineers  

DOI： 10.2208/kaigan.75.i_277

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：土木学会  

DOI： 10.2208/kaigan.75.i_283

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.3389/feart.2019.00261

Scopus

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記述言語：日本語   出版者・発行元：一般社団法人 日本風工学会  

DOI： 10.5359/jawe.44.288

CiNii Books

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記述言語：英語   掲載種別：論文集(書籍)内論文   出版者・発行元：Geological Society of London  

In this study, earthquake rupture models for future mega-thrust earthquakes in the Nankai-Tonankai subduction zone are developed by incorporating the main characteristics of inverted source models of the 2011 Tohoku earthquake. These scenario ruptures also account for key features of the national tsunami source model for the Nankai-Tonankai earthquake by the Central Disaster Management Council of the Japanese Government. The source models capture a wide range of realistic slip distributions and kinematic rupture processes, reflecting the current best understanding of what may happen due to a future mega-earthquake in the Nankai-Tonankai Trough, and therefore are useful for conducting probabilistic tsunami hazard and risk analysis. A large suite of scenario rupture models is then used to investigate the variability of tsunami effects in coastal areas, such as offshore tsunami wave heights and onshore inundation depths, due to realistic variations in source characteristics. Such investigations are particularly valuable for tsunami hazard mapping and evacuation planning in municipalities along the Nankai-Tonankai coast.

DOI： 10.1144/SP456.1

Scopus

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記述言語：日本語   出版者・発行元：公益社団法人 土木学会  

複数地点での高潮による同時・集積被害に関する研究事例はまだ数が少ない．本研究では，伊勢湾と三河湾を対象に，複数地点での高潮被災を考慮した集積リスクの評価を行った．確率台風モデルによる1000年分の仮想台風を用いて，台風経路の確認を行った．伊勢湾のみを通る192個の台風については，気象庁の経験式を使用して高潮推算を行う一方で，伊勢湾と三河湾の両地点を通る805個の台風については，高潮解析と氾濫解析を行った．さらに，三河湾の高潮解析結果から，簡易的に高潮偏差を計算する算定式を作成し，その妥当性を検討した．高潮解析結果から被害額を算定し損失関数を作成した．伊勢湾と三河湾の損失関数と各台風の高潮偏差を使用して，すべての台風の被害額を算定した．年超過確率と合計被害額の関係を表すイベントカーブを作成し，集積リスク評価を行い，1つの台風に対する期待被害額を算定した．

DOI： 10.2208/kaigan.73.I_241

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記述言語：日本語   出版者・発行元：公益社団法人 土木学会  

南海トラフ地震による津波災害が想定される太平洋沿岸の自治体では，比較的高頻度（数十年から百数十年）で発生が想定されるL1津波群を対象に，それらの最大値の包絡を採用する決定論的アプローチによって設計津波の水位が設定されている．しかし，現行の設計津波水位の決定プロセスは，L1津波の選択方法や再現期間についての議論が不十分である．本研究では，すべり分布の空間相関性を表すパラメータとすべり量を支配するパラメータに関して，地震の発生頻度や規模とパラメータの関係を表すスケーリング則を求め，確率津波モデルに適用する方法を提案した．静岡県を対象にケーススタディを行い，海岸線における津波水位を確率的に評価した．再現期間に関して，L1津波群の中の最大シナリオを採用する方法は，津波の再現期間が200年を超える可能性があることがわかった．特定の津波断層モデルをL1津波想定のモデルと定義するのではなく，津波水位を確率的に評価することが重要といえる．

DOI： 10.2208/kaigan.73.I_421

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記述言語：日本語   出版者・発行元：公益社団法人 土木学会  

沖縄諸島や太平洋諸島周辺のリーフ地形において，台風の接近・通過に伴う高潮・高波による越波災害を受けることがあり，リーフ海域特有の波浪変形特性が発災要因であることが指摘されている．そのため，リーフ海岸に護岸等の越波対策工を計画・設計する際には，リーフ上での波浪変形特性を十分に把握しておく必要がある．本研究では，リーフ地形を対象に，強非線形ブシネスクモデルを用いて波浪変形計算を行い，従来の波高変化算定式を参照しつつ，新たな算定式を提案するものであり，リーフ地形の特性を考慮した係数の算定方法により，任意の地形でも使用可能な算定式とした．本研究による提案式は，既往研究の算定式に比べて，リーフ岸沖方向の波浪変化をよく再現できた．特に，波高が大きいときの推算精度が高く，設計波高の推算に用いる際の有用性を示すことができた．

DOI： 10.2208/kaigan.73.I_43

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記述言語：日本語   出版者・発行元：公益社団法人 土木学会  

堤防高の決定には津波と高潮・高波を比較する必要があるが，これまでは既往最大値や想定値に基づいて決定論的に外力が設定されてきた．本研究の目的は，確率論的なアプローチを用いて高潮の規模と生起頻度の関係を定量化することである．検討対象地域は，既設堤防の天端高が高潮により決定され，L2津波対策が進められつつある駿河海岸を含む駿河湾とした．全球確率台風モデルを用いて駿河湾を通る5000年分の仮想台風を抽出し，非線形長波モデルを用いて高潮伝播および氾濫シミュレーションを行った．駿河湾では中心気圧と高潮偏差にほぼ比例関係があることが示された．地域海岸ごとの高潮の規模と生起頻度の関係を算定し，駿河海岸における計画高潮偏差の再現期間が約270年であることを示した．

DOI： 10.2208/kaigan.73.I_253

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SPRINGER  

Empirical tsunami fragility curves are developed based on a Bayesian framework by accounting for uncertainty of input tsunami hazard data in a systematic and comprehensive manner. Three fragility modeling approaches, i.e. lognormal method, binomial logistic method, and multinomial logistic method, are considered, and are applied to extensive tsunami damage data for the 2011 Tohoku earthquake. A unique aspect of this study is that uncertainty of tsunami inundation data (i.e. input hazard data in fragility modeling) is quantified by comparing two tsunami inundation/run-up datasets (one by the Ministry of Land, Infrastructure, and Transportation of the Japanese Government and the other by the Tohoku Tsunami Joint Survey group) and is then propagated through Bayesian statistical methods to assess the effects on the tsunami fragility models. The systematic implementation of the data and methods facilitates the quantitative comparison of tsunami fragility models under different assumptions. Such comparison shows that the binomial logistic method with un-binned data is preferred among the considered models; nevertheless, further investigations related to multinomial logistic regression with un-binned data are required. Finally, the developed tsunami fragility functions are integrated with building damage-loss models to investigate the influences of different tsunami fragility curves on tsunami loss estimation. Numerical results indicate that the uncertainty of input tsunami data is not negligible (coefficient of variation of 0.25) and that neglecting the input data uncertainty leads to overestimation of the model uncertainty.

DOI： 10.1007/s00477-016-1230-x

Web of Science

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記述言語：日本語   出版者・発行元：公益社団法人 土木学会  

本研究では，2016年に国土技術政策総合研究所から発行された「人工リーフ被覆ブロックの波浪安定性能評価のための水理実験マニュアル」に則り，六角形の孔を有するハニカム構造被覆ブロック（ハニカム型ブロック）を用いて水理模型実験を行い，ハニカム型ブロックの波浪安定性と水深波長比<i>h/L</i>が安定数<i>N_s</i>へ与える影響を評価した．実験の結果，ハニカム型ブロックは既存のブロックと比較して，安定数Nsが高いことが示された．また，<i>h/L</i>が小さくなるほど<i>N_s</i>は小さくなり，<i>h/L</i>が安定性へ影響を及ぼすことがわかった．さらに，天端水深沖波波高比が高いとき，人工リーフ岸側における波高伝達率は，矩形ブロックよりも低い値を示した．変状連鎖を調べた結果，砕波位置を起点に変状連鎖が生じた．砕波帯内においてもハニカム型ブロックは，高い安定性を有していた．

DOI： 10.2208/jscejoe.73.I_60

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：WORLD SCIENTIFIC PUBL CO PTE LTD  

Experiments were conducted at a 1:20 length scale in a large tsunami flume to measure wave evolution and pressures on and around structural elements. The water surface profiles of waves propagating across a bare beach were compared with those recorded in front of an onshore obstacle representing an urban macro-roughness element. The addition of a structure significantly changed the water surface profile for broken waves: the water surface amplification in the presence of a macro-roughness element reached seven times the bareearth water surface elevation. Estimated pressures from design equations were calculated using recommended inputs and compared with pressures recorded by gauges installed on the structural elements. Design equations showed good agreement for non-breaking wave pressures but underestimated peak pressures for breaking waves. Likewise, force integrations of measured pressures on the experimental specimen indicated that design equations may underestimate loads due to waves that break offshore and propagate across a beach as a turbulent bore. The time-integrated pressure impulse was shown to be less sensitive to wave characteristics than the peak recorded pressures. Time-averaged loading curves were also developed for different average periods.

DOI： 10.1142/S0578563417500048

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記述言語：英語   出版者・発行元：ELSEVIER SCIENCE BV  

The influence of flow velocity on structural damage induced by tsunami inundation is investigated to improve empirical fragility models considering flow velocity as explanatory hazard variable in addition to inundation depth. The analysis is based on extensive tsunami damage data for the 2011 Tohoku earthquake collected by the Ministry of Land, Infrastructure, and Transportation of the Japanese Government. Multivariate tsunami fragility curves are developed through multinomial logistic regression of un-binned data. This approach facilitates the flexible development of various nested models considering inundation depth alone or inundation depth and velocity altogether. Statistical diagnostic metrics, such as the Bayesian Information Criterion, the Akaike Information Criterion, and the residual deviance, are used to determine which model improves the predictability of tsunami damage. The significance and importance of including flow velocity in the vulnerability models are assessed quantitatively by examining the influence of different spatial resolutions in elevation model and different source models. Then, the effects of coastal topography have been investigated. Numerical results show that flow velocity generally improves the fragility models, particularly for severer structural damage states, and that it is important for sites along the coast where the inundation depth is not extremely high. Coarse digital elevation model and inaccurate source models have influence on the calculated values of flow velocity and thus they affect the accuracy of fragility modeling. Finally, two different fragility models are calibrated for plain type and ria-type coasts by reflecting differences in hydrodynamic behavior and recorded damage on the structures. (C) 2017 The Authors. Published by Elsevier B.V.

DOI： 10.1016/j.earscirev.2016.12.015

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

This paper presents data and analysis for block and boulder transport during Super Typhoon Haiyan along a 4.5 km long, low (5-12 m) cliffed coastline in Calicoan Island, Eastern Samar, Philippines. Wave runup exceeding 15.2 in elevation above mean sea level drove large limestone clasts, with volumes up to similar to 83 m(3), up to similar to 280 in inland. A few very large clasts with volumes 65-132 m(3) were not transported by the waves. When combined with recent transport reported in May et al. (2015), Cox et al. (2016), and other literature, it is becoming increasingly clear that the largest blocks transported by storms overlie much of the tsunami transport range, increasing the difficulty in attributing the transport source without additional evidence. Comparison of present results with a global database of storm boulder transport shows a mass-elevation envelope outside of which no transport is observed.
Initiation of motion criteria were extended to include non-rectangular cross-sections, which significantly reduces inferred velocities, particularly for overturning motion. These new relations were applied to the largest observed sliding and overturning boulders while considering coefficient uncertainties, and resulting velocity uncertainty was large enough that direct inference of wave heights would be problematic. Estimates of initiation velocities for cliff-edge boulders computed using lifting/joint-bounded relations were unreasonably large when compared to those for sliding and overturning boulders, suggesting that processes other than Bernoulli lift forces dominated at cliff edges. (C) 2016 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.margeo.2016.11.004

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掲載種別：研究論文（学術雑誌）  

DOI： 10.3389/fbuil.2017.00034

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

Wave experiments were conducted on a 1:20 length scale to measure water surface elevations and extreme pressures on and around idealized structural elements and arrays of structures. Experiments varied offshore wave characteristics and onshore structural configurations. Conditions in which waves broke on or just before the specimen caused maximum impulsive pressures. Pressures measured under nonbreaking wave conditions agreed with predicted values using design equations suggested by the Japanese Cabinet Office; however bare-earth water surface elevation inputs produced nonconservative estimates in breaking wave trials. Shielded structures experienced pressure reductions of 40-70% under breaking wave conditions. Results indicate that shielding elements constructed nearshore may reduce wave-induced damage. This dataset may be used to validate numerical models of tsunami propagation through urban environments. (C) 2016 Published by Elsevier B.V.

DOI： 10.1016/j.coastaleng2016.07.003

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記述言語：日本語   出版者・発行元：公益社団法人 土木学会  

海洋を対象とした波浪や流れおよび塩熱環境の再解析には，数値モデルの構築において対象スケールに適した物理素過程を考慮することが重要である．実際の波浪場は風波やうねりの共存する不規則波浪場であるが，沿岸域において，その重要性のわりに不規則波による波・流れ相互作用はあまり考慮されてこなかった．本研究では，砕波帯外の海域で波・流れに及ぼす影響として重要な不規則波浪場のStokes driftについて領域スケールの海洋・波浪結合モデルに考慮した．構築した結合モデルを用いて和歌山県田辺湾を対象とした沿岸流の解析を行い，既存のモデルの計算結果と比較を行った．単一の海洋モデルおよび規則波に対するStokes driftを考慮した結合モデルでは，Stokes driftを全体的に過大評価傾向にあったが，本結合モデルではStokes driftの平均流への30%程度の影響があることを明らかにした．

DOI： 10.2208/kaigan.72.I_511

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記述言語：日本語   出版者・発行元：公益社団法人 土木学会  

津波浸水想定の際，数値シミュレーションは有効な手段となり得るが，陸上における土地利用や市街地の複雑さは粗度として扱われ，局所的な浸水深や浸水範囲の精度と再現性に関して検証が行われていない．本研究では，津波再現水槽と沿岸市街地模型を用いて浸水実験を実施し，浸水深や浸水範囲，波圧を計測し，シミュレーション結果との比較を通して，市街地の複雑な地形が遡上に及ぼす影響について考察した．実験に当たっては，津波再現水槽で対象とする任意の複雑な津波波形を再現し造波する方法を確立した．津波計算を行う際に建物の密集度を考慮することの重要性や，津波の遡上過程において，平均地盤高からの比高が高く幅が広い線的構造物は，粗度ではなく地形として取り扱う必要があること，および，津波波圧算定式は，多方向から浸水する場所では過小評価になる可能性があることを示した．

DOI： 10.2208/kaigan.72.I_385

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記述言語：日本語   出版者・発行元：公益社団法人 土木学会  

JRA-55長期再解析と，これをもとに計算された波浪解析値を基本データとし，大気情報から波高を計算する統計的波高予測モデルを開発した．各計算格子点において，ある時点の場の風と気圧の情報のみから波高計算を行う従来モデルに，気圧の主成分の時係数を説明変数として加えて，うねりを考慮可能とした．気圧の主成分を考えることにより，その場の風や気圧の情報のみから計算を行う従来モデルと比較して，大幅な精度の向上を得た．特に従来モデルで相関の良くなかった海域において，誤差を大きく減少させることができ，中でも夏季の波高減少や冬季の波高増加の季節変動特性の過小評価が改善された．

DOI： 10.2208/kaigan.72.I_139

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記述言語：日本語   出版者・発行元：公益社団法人 土木学会  

複数地域の同時被災を考慮した高潮リスク評価は，これまでほとんど行われていない．本研究では，日本の主要な湾を対象に，複数地域での同時被災を考慮した高潮災害の集積直接経済リスク評価手法の開発を行った．確率台風モデルによる1000年分の仮想台風を用い，複数地域を通る台風の通過確率を求めた．そのすべての台風について簡易式を用いて高潮を算定する一方で，一部の強い台風について高潮氾濫解析を行って被害額を求め，損失関数を求めた．この損失関数を用いてすべての台風の合計被害額を算定し，被害額と再現期間（年超過確率）で表されるイベントカーブをリスク評価に用いた．三大湾の集積リスクを考慮した場合，再現期間の長い台風では，伊勢湾と大阪湾で同時被災するリスクが最も大きく，再現期間の短い台風では，大阪湾1地域のみ被災するリスクが最も大きくなった．最大クラスシナリオを考える際には，本評価手法で複数地域での集積リスクを考慮する必要があることを示した．

DOI： 10.2208/kaigan.72.I_1639

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：WORLD SCIENTIFIC PUBL CO PTE LTD  

New scaling relationships of key earthquake source parameters are developed by uniformly and systematically analyzing 226 finite-fault rupture models from the SRCMOD database (http://equake-rc.info/srcmod/). The source parameters include the fault width, fault length, fault area, mean slip, maximum slip, Box-Cox power, correlation lengths along dip and strike directions, and Hurst number. The scaling relationships are developed by distinguishing tsunamigenic models from non-tsunamigenic models; typically, the former occurs in ocean and has gentler dip angles than the latter. The new models are based on extensive data, including recent mega-thrust events, and thus are more reliable. Moreover, they can be implemented as multivariate probabilistic models that take into account uncertainty and dependency of the multiple source parameters. The comparison between new and existing models indicates that the new relationships are similar to the existing ones for earthquakes with magnitudes up to about 8.0, whereas the relationships for the fault width and related parameters differ significantly for larger mega-thrust events. An application of the developed scaling relationships in tsunami hazard analysis is demonstrated by synthesizing stochastic earthquake source models in the Tohoku region of Japan. The examples are aimed at providing practical guidance as to how the developed scaling relationships can be implemented in stochastic tsunami simulation. The numerical results indicate that the effects of magnitude scaling of the source parameters and their uncertainties have major influence on the tsunami hazard assessment.

DOI： 10.1142/S0578563416500108

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：International Society of Offshore and Polar Engineers  

Tsunamis generated by earthquakes commonly propagate as long waves in the deep ocean and develop into sharp-fronted surges moving rapidly toward the coast in shallow water, which may be effectively simulated by hydrodynamic models solving the nonlinear shallow water equations (SWEs). However, most of the existing tsunami models suffer from long simulation time for large-scale real-world applications. In this work, a graphics processing unit (GPU)-accelerated finite volume shockcapturing hydrodynamic model is presented for computationally efficient tsunami simulations. The improved performance of the GPU-accelerated tsunami model is demonstrated through a laboratory benchmark test and a field-scale simulation.

DOI： 10.17736/ijope.2016.ak10

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：WORLD SCIENTIFIC PUBL CO PTE LTD  

Boulders numbering in the high hundreds/low thousands, and with masses up to similar to 30 tonnes, were transported onshore by Super Typhoon Haiyan in Calicoan Island, Philippines to maximum ground elevations that could exceed 9m and terminal positions up to similar to 180m inland. One-dimensional Boussinesq hindcasts of coastal boulder motion showed intermittent transport initiated at the fronts of infragravity swash bores. Transport distances were found to be highly sensitive to wave-height, enough so that observations of terminal positions may be a viable method of estimating rough paleostorm magnitudes. The large accelerations at bore fronts generated significant inertial forces, particularly for larger boulders, but drag forces had greater root-mean-square magnitudes in all simulations. Widely used relations to infer fluid velocities from boulder properties were tested using modeled boulders - inferred velocities at modeled terminal boulder positions were compared to maximum computed Boussinesq fluid velocities at these locations and found to be significantly lower. This underprediction of inferred velocities was greatest for smaller boulders that were strongly mobile. Inferred drag loads compared to modeled values were somewhat more accurate for large boulders when a Froude number of unity was assumed to estimate flow depths. Although these boulders were unequivocally transported by storm waves, their large sizes and distances traveled venture into what has been considered the tsunami range. Thus, care must be taken to interpret the provenance of coastal boulder fields with unknown origin for lower to mid-latitude regions.

DOI： 10.1142/S0578563416400040

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DOI： 10.17265/1934-8975/2016.03.004

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCI LTD  

The present study investigates how the wind speed limited wave dependent drag coefficient (C-D) influences the surge and wave generation of Super Typhoon Haiyan, which struck the coasts of the Leyte Gulf, in the Philippines (2013), using a coupled surge and wave model. In addition, we examine the effect of changes of the radius (R-max which the maximum wind speed occurs. Accurate determination of this radius is crucial to the Haiyan wind and pressure field when using a parametric wind and pressure model because of lack of observation data. The calculation results show that the radius ranges from 40 km to 50 km: as the radius becomes narrower, the surge and wave heights are reduced. Our calculation of surge and wave levels uses a modified version of Janssen' method (Janssen, 1989, 1991) with a step function applied to level off C-D in the exponential wave growth term. In the present method, the wind speeds are limited to a certain threshold; below this value the effective roughness is estimated with a logarithmic wind profile. With the newly modified method, we investigate the effect of the wind speed-limited wave dependent drag C-D for high winds (&lt;70 m/s) on the Haiyan surge and wave levels. When leveling off C-D at 25 m/s for R-max = 50 km good agreement with survey data is obtained in terms of surge level (6.5 m) and wave heights (7 m and 17 m inside and outside of the gulf). The numerical experiments suggest that leveling off at wind speeds of 25-30 m/s results in the accurate prediction of Haiyan storm surge and wave levels in the coupled surge and wave model. The study demonstrates the applicability of the present method of leveling off at wind speeds of 25-30 m/s in a coupled surge and wave model for super typhoon conditions. (C) 2015 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.ocemod.2015.06.004

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

気候変動予測の（不）確実性は，複数の予測結果間の整合性で評価される．本研究では，複数の予測結果間の（不）確実性を評価するため，単一の気候モデルと波浪モデルを用いた複数の実験条件によるシングルGCMアンサンブル実験，および，CMIP5の8つのGCMを用いたマルチGCMアンサンブル実験にもとづき，温暖化条件下の波候の将来予測を実施し，これらの（不）確実性の評価を行った．その結果，北西太平洋北緯30°付近の冬季における平均波高の減少が予測され，その傾向はアンサンブル間で非常に整合性があること，また，北西太平洋の冬季平均波高の減少は，大気循環場が元来有している変動パターンの1つであるWest Pacific (WP)パターンの正の変化（北西太平洋高緯度における気圧低下）に良く対応していることを明らかにした．

DOI： 10.2208/kaigan.71.I_1525

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その他リンク： https://jlc.jst.go.jp/DN/JLC/20017142661?from=CiNii

記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

気象庁が開発した55年間の大気再解析値JRA-55をもとに，波浪の長期推算を行った．波浪推算は，スペクトル型波浪モデルWAVEWATCHIIIの2種類のソース項の組み合わせを用いて行った．得られた波浪推算結果をブイおよび衛星高度計の観測値と比較検証し，ERA-40/Interrim に比べて平均波高および極大波高について良い精度を持つことを明らかにした．また年最大有義波高等の極大波浪についても，JRA-55の推算精度は高く，熱帯低気圧の発生域を除くとJRA-55にもとづく極値分布は，観測値にかなり近い分布形状を示すことを明らかにした．

DOI： 10.2208/kaigan.71.I_103

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その他リンク： https://jlc.jst.go.jp/DN/JLC/20017144269?from=CiNii

記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

気候変動に伴い熱帯低気圧の強度は増大する可能性が高く，沿岸部においては高潮による浸水被害リスクの高まりが懸念される．気象研究所の水平解像度60kmの全球気候モデルGCMでは，複数の海面水温SSTパターンや排出シナリオについて気候変動のアンサンブル将来予測実験が行われているが，高潮の直接計算に駆動力として用いるのは精度的に不十分である．本研究では，領域気候モデルRCMを最も精度の高い出力値と見なして，RCMとGCMとの間に生じるモデル間の出力値の差を補正するバイアス補正手法を開発した．バイアス補正した気圧・風速データを駆動力として，SSTの違いによる高潮の将来変化のアンサンブル予測をした．その結果，異なるSSTクラスターで高潮の将来変化の分布は台風経路に依存して異なったが，全クラスターに共通して高潮の再現確率値が増大する湾があることが示された．

DOI： 10.2208/kaigan.71.I_1507

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その他リンク： https://jlc.jst.go.jp/DN/JLC/20017142609?from=CiNii

記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

現行の設計基準では，越波流量あるいは打上げ高に基づいて海岸護岸の天端高を決定するが，それぞれの安全性水準が異なる可能性が指摘されてきた．Mase et al.¹⁾は汀線近傍に設置された傾斜護岸を対象に，打上げ・越波統合算定モデル(IFORM)を提案したが，堤脚水深の大きい場合の推定精度は明記されておらず，また直立護岸は対象外であった．本研究は，IFORMについて，堤脚水深の大きな箇所に設置された傾斜護岸への適用性を検討するとともに，直立護岸にも適用できるよう拡張したものである．CLASHプロジェクトによるデータセット2)で検証した結果，IFORMは堤脚水深が大きい傾斜護岸にも適用でき，2割勾配護岸の越波流量に対する補正係数を適用することで，直立護岸にも拡張できることが確認された．

DOI： 10.2208/kaigan.71.I_847

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その他リンク： https://jlc.jst.go.jp/DN/JLC/20017143774?from=CiNii

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

近年，地球温暖化に伴う気候変動による自然災害の脅威が増している．このような状況下において，海岸堤防の整備に関しては，海面上昇や台風の大型化に伴う波の増大に適応していくことが喫緊の課題となっている．そこで本研究は，信頼性解析（レベル3）を用いた海岸堤防天端高の算定方法の気候変動への適応について，現在および将来気候条件を対象に従来法におけるそれとの比較を通して考察した．その結果，従来法により設定される想定の海岸堤防の必要天端高は，安全性が過剰となる可能性が示唆された．本研究で提案する現在気候と同一安全水準を有するための将来の嵩上げ高算定値は，許容越波流量や高潮偏差の影響をあまり受けず，従来法よりも小さく算定されることが示された．

DOI： 10.2208/kaigan.71.I_1183

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その他リンク： https://jlc.jst.go.jp/DN/JLC/20017144450?from=CiNii

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

日本海沖では，稀に冬季を中心に急速に発達し台風並みの暴風雨をもたらす温帯低気圧が発生する．一方，太平洋沖では，夏季に台風が接近または上陸し，両者は沿岸部に大きな被害をもたらす．近年の研究により，波浪のスペクトル形状から最高波高<i>H</i>_maxの頻度や期待値を求めるという方法が提案されている．しかし，実際の気象条件下で，どの程度の精度で推定可能かは不明である．そこで本研究では，ここ数年で特徴的な気象擾乱である，2012年4月に発生した日本海低気圧と同年9月に発生した台風1216号，および2014年10月に発生した台風1418号を対象に，スペクトル型波浪モデルを用いて有義波高<i>H</i>_1/3および最高波高<i>H</i>_maxの推計を行った．

DOI： 10.2208/kaigan.71.I_457

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その他リンク： https://jlc.jst.go.jp/DN/JLC/20017138978?from=CiNii

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

Most of breakwaters which were damaged by the 2011 Tohoku tsunami have been reconstructed to withstand the same <i>M_w</i> 9.0 earthquake or smaller intensity. However, as the same tsunami is unlikely to occur, future tsunami defense strategy should consider the variability of tsunami sources. This study investigates breakwater stability against uncertain tsunamis using a stochastic tsunami source model for the 2011 Tohoku earthquake. The analysis of the tsunami profiles in five Tohoku ports demonstrated that the locations and topography of these ports strongly influence the variability of the maximum tsunami wave height. The results of the stability analysis confirm that the breakwater stability in the ports depends on tsunami wave profiles affected by regional features. The key findings from this paper suggest that future tsunami defense policy should take into account uncertainty and variability in tsunami wave profiles and regional features of tsunami amplification.

DOI： 10.2208/kaigan.71.I_895

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その他リンク： https://jlc.jst.go.jp/DN/JLC/20017143842?from=CiNii

J-GLOBAL

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：WORLD SCIENTIFIC PUBL CO PTE LTD  

Crown heights of seawalls should be designed to suppress overtopping discharge to a permissible level. The permissible level is determined from viewpoints of the structure types of coastal seawalls and hinterland use. It is usually difficult to design the crown heights of seawalls, especially in the present time where climate change due to global warming is expected. This study analyzes climate change effects such as sea level rise (SLR) and increase of waves and surges on the failure probability of seawalls under various conditions of crown height, toe depth and slope by using a Level III reliability analysis. It was found that the difference of SLR trends (fast, medium or low) has less impact on overtopping rates than the differences in wave height change for a seawall at a target location.

DOI： 10.1142/S0578563415500102

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：WORLD SCIENTIFIC PUBL CO PTE LTD  

A computational framework for probabilistic tsunami risk assessment due to a mega-thrust subduction earthquake is developed and is applied to the 2011 Tohoku Tsunami from retrospective viewpoints. The uncertain tsunami source characteristics are represented by multiple source inversion models and their stochastic variations that are generated using the spectral analysis and synthesis method. By conducting Monte Carlo tsunami simulation, stochastic inundation depth maps can be developed, which are subsequently integrated with tsunami fragility curves to develop stochastic tsunami risk maps. The stochastic tsunami risk maps display spatial variability of tsunami damage probabilities for a building portfolio, reflecting not only possible tsunami scenarios but also uncertain tsunami resistance of buildings. The numerical results indicate that both stochastic tsunami risk maps and risk curves are affected by the local terrain features, proximity to major tsunami sources, and building characteristics (material type and story number). Consideration of different reference tsunami source models in probabilistic tsunami risk assessment are identified as one of the critical contributors to the overall uncertainty of the tsunami risk predictions. Therefore, in determining critical scenarios for tsunami evacuation and risk mitigation, a wide range of possible tsunami scenarios should be considered in light of the current limited seismological knowledge for the mega-thrust subduction earthquake.

DOI： 10.1142/S0578563415500151

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

本研究は，流体解析ツールOpenFOAM (Open source Field Operation And Manipulation)を用いて，リーフ上の浅瀬を伝播する津波の変形過程，特にソリトン分裂に注目して，その再現性を検討した．同時に，オープンソースのCOULWAVEおよびFUNWAVEによる計算結果との比較を行った．OpenFOAMは，入射津波の第1波のソリトン分裂とソリトン波列の伝播，岸側固定壁でのソリトン波列の反射等，実験結果ををかなり良く再現できた．COULWAVEおよびFUNWAVEは，第1波目のソリトン分裂を再現できず，第2波目の入射波ではソリトン分裂が現れるが，位相，波の数，振幅が実験結果と一致しないこと等，全般的に実験結果との対応が良くないことがわかった．

DOI： 10.2208/kaigan.71.52

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER GEOPHYSICAL UNION  

The sensitivity and variability of spatial tsunami inundation footprints in coastal cities and towns due to a megathrust subduction earthquake in the Tohoku region of Japan are investigated by considering different fault geometry and slip distributions. Stochastic tsunami scenarios are generated based on the spectral analysis and synthesis method with regards to an inverted source model. To assess spatial inundation processes accurately, tsunami modeling is conducted using bathymetry and elevation data with 50 m grid resolutions. Using the developed methodology for assessing variability of tsunami hazard estimates, stochastic inundation depth maps can be generated for local coastal communities. These maps are important for improving disaster preparedness by understanding the consequences of different situations/conditions, and by communicating uncertainty associated with hazard predictions. The analysis indicates that the sensitivity of inundation areas to the geometrical parameters (i.e., top-edge depth, strike, and dip) depends on the tsunami source characteristics and the site location, and is therefore complex and highly nonlinear. The variability assessment of inundation footprints indicates significant influence of slip distributions. In particular, topographical features of the region, such as ria coast and near-shore plain, have major influence on the tsunami inundation footprints.

DOI： 10.1002/2014JC010626

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Springer International Publishing  

The effects of wave steepness and wave breaking on the stability of wave-dissipating blocks placed on caisson breakwaters are examined by hydraulic experiments under conditions with and without wave breaking. It is confirmed that there is a clear dependence of the block stability on the wave steepness through the wave-breaking type, such as plunging and spilling breakers. The stability parameter in the spilling breaker case is larger than that in the plunging breaker case. For non-breaking wave conditions, there is no effect of the wave steepness. An empirical stability formula is proposed taking into account the effects of the wave steepness and the wave-breaking type. Finally, by using the stability formula, failure probabilities of the wave-dissipating blocks having a nominal diameter are evaluated by the first-order reliability method of the Level II reliability analysis.

DOI： 10.1007/s40722-014-0004-0

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Japan Society of Civil Engineers  

東日本大震災においては，津波の越流が生じて多くの海岸堤防が破壊された．特に，コンクリートブロックで被覆した三面張りの堤防は，裏法面のブロックや内部の地盤が流されて特異な形態で破壊した．三面張り堤防の破壊メカニズムは水理実験や流体解析などによって検討されているが，地盤の挙動を含めた検討は進んでいない．そこで本研究では，地盤を含んだ模型実験を実施して地盤挙動を含めた越流による三面張り堤防の破壊特性を観察した．実物スケールの地盤の応力状態や水圧状態を再現できる遠心模型実験を津波越流問題に適用したことを特徴としている．模型実験によって，裏法面を流れる越流水の影響に，堤防内部の地盤での浸透現象が複合することで堤防が破壊に至る過程を観察した．

DOI： 10.2208/kaigan.71.42

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

東日本大震災における教訓を今後の地震・津波防災対策にいかに反映すべきか，多くの課題が議論されている．とりわけ災害時におけるマクロな視点での水循環の確保とそのための施設整備のあり方を，地域要件，時間軸，その他，上下水道サービスを受益するエンドユーザーの視点も踏まえた現実的な方針決定を施策として実行することが不可欠となる．そのため，上下水道等のライフラインを管理する自治体においては，災害時における適正な水循環（質，量）の確保の視点から，当該地域における想定地震・津波規模に相応した現実的な対応力（人，物）や財政力（金）等を踏まえた地震・津波防災対策の基軸となる方針決定を早期に策定することが重要な課題と考える．本研究では，そのための施策について「戦略的な水循環ネットワーク確保」をテーマに今後の研究を進める上での懸案事項の整理や検討すべき具体的な着目点を基礎研究としてとりまとめ，さらに高知市をフィールドにした具体的なケーススタディ事例を示す．

DOI： 10.2208/jscejseee.71.I_915

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

これまでは，長ストロークのピストンタイプ造波機を用いて，造波板を最後部に引いて，前に押しだして孤立波を作成することで疑似的に津波を造波することが多かった．しかし，そのあとに続く強い流れは再現できず，臨時で，水流ポンプを設置したものが一部で使用されていた．また津波には，地震だけでなく局所地滑りや氷塊の落下によるダムブレイク的な発生メカニズムも存在しており，それらに対する考慮も必要である．そこで，複雑で多様な津波波形をできるだけ再現し現地の破壊メカニズムを検証するために，3つの造波機能を有する津波再現装置を開発した．3つの機能は，1）ピストンタイプ造波機による孤立波の造波，2）流れ発生装置による水流の発生，3）水塊落下装置によるダムブレイクの再現，である．本研究ではこれらの手法を単一および複数組み合わせた場合の再現津波の特性を検討した．

DOI： 10.2208/kaigan.71.I_349

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その他リンク： https://jlc.jst.go.jp/DN/JLC/20017141923?from=CiNii

記述言語：日本語  

J-GLOBAL

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

静水圧近似した平面2次元（2D）と準3次元（Q3D）モデルを用いて，市街地を対象とした津波遡上実験の再現計算を行った．Q3Dモデルの計算は，遡上波に平行な構造物列間では良好な結果を示すが，構造物背後での計算精度は不十分であった．また，水平渦粘性係数を変化させて行った解析結果より，市街地のように波の進行幅が変わりやすい地形では，渦粘性係数の値が波の進行する速度に大きく影響することが確認された．さらにQ3Dモデルと2Dモデルの解析結果の比較により，浸水深が減少する内陸部においては，同じ計算条件でも2つのモデル間の浸水範囲等の差異が大きくなり，特に2Dモデルでは底面摩擦係数の影響が大きくなることを確認した．

DOI： 10.2208/kaigan.71.I_169

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その他リンク： https://jlc.jst.go.jp/DN/JLC/20017141459?from=CiNii

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：American Society of Civil Engineers (ASCE)  

The present study aims at the development of after-runner storm surge (ARS) forecast model using an artificial neural network in Sakai Minato and Hamada on the Tottori Coast, Japan, that is made in 30 hours in advance. To develop an artificial neural network-based ARS forecast model, local meteorological and hydrodynamic parameters (surge level, sea-level pressure, depression rate of sea-level pressure and typhoon location of longitude and latitude) on the Tottori Coast are collected. A series of experiments is carried out to improve the ARS forecast model as varying the unit number from 13 to 130. As a result, it was found that the accuracy of ARS forecast model is improved as increasing the unit number. Then, we can obtain the best performance of the ARS forecast model with the given lead time. In addition, the optimal unit number for the given lead time can be determined.

DOI： 10.1061/9780784480304.024

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Elsevier Ltd  

In the present study, the after-runner surge that maximum surge height appears 15-18 h later along the Tottori coasts facing the Sea of Japan/East Sea (SJES) after typhoons undergo a change in shape and intensity as extratropical cyclones is investigated using asymmetric and symmetric wind and pressure fields of Typhoon Songda (2004). For the asymmetric wind and pressure field, the Weather Research and Forecasting (WRF) model is used, while for the symmetric wind and pressure field, a parametric wind and pressure model is used. The results indicate that both models simulate fairly well the 10 m level wind and the sea level pressure along the Pacific Ocean, while the WRF model shows better agreement with the observations over the SJES. Subsequently, from storm surge simulations for Typhoon Songda, it is found that using the deformed and asymmetric meteorological field of typhoon structures agrees well with observations. The study shows that the after-runner surge's characteristic comes from the Ekman setup in the presence of the Coriolis force over the Tottori coasts. It is critical that its behavior should be taken into account for the safety design of coastal defense structures around the Tottori coastal region.

DOI： 10.1016/j.oceaneng.2014.09.005

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SPRINGER HEIDELBERG  

In this study, we develop stochastic random-field slip models for the 2011 Tohoku earthquake and conduct a rigorous sensitivity analysis of tsunami hazards with respect to the uncertainty of earthquake slip and fault geometry. Synthetic earthquake slip distributions generated from the modified Mai-Beroza method captured key features of inversion-based source representations of the mega-thrust event, which were calibrated against rich geophysical observations of this event. Using original and synthesised earthquake source models (varied for strike, dip, and slip distributions), tsunami simulations were carried out and the resulting variability in tsunami hazard estimates was investigated. The results highlight significant sensitivity of the tsunami wave profiles and inundation heights to the coastal location and the slip characteristics, and indicate that earthquake slip characteristics are a major source of uncertainty in predicting tsunami risks due to future mega-thrust events.

DOI： 10.1186/1880-5981-66-105

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER GEOPHYSICAL UNION  

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 the western North Pacific Ocean. The characteristics of Typhoon Haiyan and its related storm surge are estimated by numerical experiments using numerical weather prediction models and a storm surge model. Based on the analysis of best hindcast results, the storm surge level was 5-6m 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 to the specific bathymetry of Leyte Gulf and the Philippines Trench as a major contributor to the disaster in Tacloban. The numerical results also indicated the sensitivity of storm surge forecast.

DOI： 10.1002/2014GL060689

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER METEOROLOGICAL SOC  

A global stochastic tropical cyclone model was developed as a means for preparing a large number of artificial tropical cyclone (TC) samples with different values for parameters such as track, minimum sea level pressure, and translation speed. In this paper, the model and the results of its verification are presented in detail. The proposed stochastic model is sensitive to approximations of the joint probability distribution functions (PDFs) of TC parameters and temporal correlations. A newly introduced accurate method for approximating joint PDFs by using principal component analysis and cluster analysis resulted in improved reproducibility of TC parameters. The simulation results were compared with historical observational data from the northwestern Pacific, southwestern Pacific, and North Atlantic Oceans. The grid-averaged mean values and distribution patterns of PDFs of TC parameters were in agreement with observational data.

DOI： 10.1175/JAMC-D-13-08.1

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：WORLD SCIENTIFIC PUBL CO PTE LTD  

Japan Society of Civil Engineers (JSCE) and Philippine Institute of Civil Engineers (PICE) jointly collaborated to carry out the field survey on severe storm surge disasters caused by Typhoon Haiyan/Yolanda from 12 December to 16 December, 2013 in Leyte and Samar. Based on interviews with local residents, the joint survey team obtained measured inundation and run-up heights at almost 80 different locations along the coast and also at more than 70 locations inside the cities of Tacloban and Palo. Clear contrast of inundation characteristics was observed especially among east coast of Eastern Samar, inner and southern parts of San Pedro Bay. While inner part of San Pedro bay, as was expected, showed relatively high inundation heights, east coast of Leyte also had comparably high inundation heights even outside the San Pedro Bay. It should also be highlighted that surprisingly high inundation heights were observed along the east coast of Eastern Samar, which faces to the Pacific Ocean with deep Philippine Trench. This paper aims to report primary results obtained through the first joint field survey of JSCE and PICE.

DOI： 10.1142/S0578563414500065

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掲載種別：研究論文（学術雑誌）  

At 14:46 local time on March 11, 2011, a magnitude 9.0 earthquake occurred off the coast of northeast Japan. This earthquake generated a tsunami that struck Japan as well as various locations around the Pacific Ocean. With the participation of about 300 researchers from throughout Japan, joint research groups conducted a tsunami survey along a 2,000 km stretch of the Japanese coast. More than 5,200 locations have been surveyed to date, generating the largest tsunami survey dataset in the world. The inundation height and run-up height were surveyed by laser, GPS, and other instruments, and the tidal correction has been accurately adjusted using a tidal database and a numerical simulation for Tohoku, an area where tide gauges were destroyed by the tsunami. Based on the survey dataset, the regional and local scale analyses were conducted to understand the basic characteristics of this event. Maximum run-up heights greater than 10 m are distributed along 500 km of coast in direct distance. The affected area of this event was several times larger than historically recorded in Tohoku. The mean inundation height in the southern Sanriku region is 1015 m and there are several peaks of inundation along the coast from the northern to middle part of Sanriku. © 2012 World Scientific Publishing Company and Japan Society of Civil Engineers.

DOI： 10.1142/S0578563412500015

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

The present study evaluates future storm surge risk due to tropical cyclones (typhoons) in East Asia. A state-of-the-art atmospheric general circulation model (GCM) outputs are employed as the driving force for simulating storm surges associated with the projected changes in climate. The reproducibility of tropical cyclone (TC) characteristics from the GCM in the Northwest Pacific (NWP) is confirmed by comparing with the observed best track data, and future typhoon changes were presented. Storm surge simulation is carried out for East Asia, with the finest nested domain on the Japanese coast. The probability of maximum storm surge heights with specified return periods is determined using extreme value statistics. We show a strong regional dependency on future changes of severe storm surges. (C) 2013 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.coastaleng.2013.10.003

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

The strong typhoon Sanba crossed the east side of Japan in September, 2012. The minimum central pressure of the Sanba reached 900 hPa. The typhoon generated wind waves more than 15 m in the significant wave height and gave severe damages to coastal structures. This study analyzed observed wave records at 10 stations along the typhoon track. A series of numerical analysis was performed to understand the characteristics of extreme sea condition by the typhoon. The maximum wave heights were estimated based on the spectral wave model and the nonlinear short wave statistical theory. The observed data shows the nonlinear enhancement of maximum wave height slightly. The estimated maximum wave height by the nonlinear theory shows better agreement with the observed peak of maximum wave height than that by the linear theory.

DOI： 10.2208/kaigan.70.I_121

CiNii Books

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その他リンク： https://jlc.jst.go.jp/DN/JALC/10041328353?from=CiNii

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：ICE Publishing  

Recently, caisson sliding failures affected by large waves have occurred. The damage of the breakwaters in Susami port due to Typhoon Tokage on October 2004 is a typical sliding failure and the caissons were tilted down in the rear of rubble mound. The damage at Fushiki-Toyama port on February 2008 is also another typical sliding failure and concrete blocks were settled down. The present paper describes the factors of their caisson sliding failures affected by damage of armor concrete blocks. It concludes that the caisson sliding failure at Susami port was caused by insufficient weight of the caisson. Even if heavier concrete blocks are placed as armors, the caisson would be slid. The numerical simulation suggests that the caisson sliding failure at Fushiki-Toyama port was caused by the combination of three factors of large wave height, long wave period and duration time.

DOI： 10.1680/fsts.59757.0262

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：ICE Publishing  

Understanding future changes of storm waves are important for assessing and mitigating the impact of climate on coastal, marine and ocean environments and on engineering problems. Focusing on extreme wave conditions, tropical cyclone activity plays a major coastal force in the tropical to middle latitudes in the summer. Global wave climate projections were performed by the spectral wave model using sea surface winds at 10 m height Uia of the general circulation model (GCM). Extreme values of significant wave height Hs were analyzed by the extreme value analysis for present and future climates respectively. There are clear increases in 50-year return values of Hs in the tropical cyclone dominant regions around the middle latitudes of the Northwest Pacific, the Northeast Pacific and other regions. The influences of future climate change on caisson breakwater are discussed considering sea level rise, extreme wave conditions and storm surges targeted the Pacific side of Japan. The influence of tropical cyclone generated extreme waves is major factor of long-term use of coastal structures in the target area.

DOI： 10.1680/fsts.59757.0204

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DOI： 10.9753/icce.v34.currents.23

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

The Coast Act was amended, and in addition to "protection", elements of "environment" and "use" were added. The method of evaluating these three elements objectively and determining a priority to perform suitable coastal preservation in a limited source of revenue has not been developed yet. Thus, this research develops a systematized method using the Analytic Hierarchy Process for the priority assessment of coastal preservation. Five criterions, which are "importance of hinterland", "aging of structures", "use", "economy", and "environment", are employed for the assessment. As a result of using the method, it turned out that evaluation of the priority of coastal preservation in Osaka Bay is possible. Furthermore, it is expectable that more accurate assessment can be performed by using more additional evaluation criteria and detailed data.

DOI： 10.2208/kaigan.70.I_1391

CiNii Books

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その他リンク： https://jlc.jst.go.jp/DN/JALC/10041328759?from=CiNii

記述言語：日本語   出版者・発行元：地盤工学会  

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

Crown height of a seawall should be designed to suppress overtopping discharge into an allowable level. The allowable level is determined from the viewpoints of the structure type of coastal seawalls and the hinterland use. Since environmental coastal forces, such as sea levels, waves and storm surges, have probabilistic nature, it is usually difficult to design the crown height, especially under the present condition where climate change due to global warming is expected in the future. This study analyzes climate change effects on failure probability of seawalls by using a reliability analysis method of level III and proposes a method to keep the present safety level in the future climate.

DOI： 10.2208/kaigan.70.I_1281

CiNii Books

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その他リンク： https://jlc.jst.go.jp/DN/JALC/10041328513?from=CiNii

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

In local disaster prevention plan, few local municipalities consider unexpected tsunamis, and most of them make a tsunami inundation hazard map following a scenario which is provided by the central government. Hazard map which shows ranges and uncertainties of the assumption can be more reasonable to understand the tsunami risks in the local scale. Local municipalities also should know the disaster resistance capacity of the region in advance to adjust occurrence of unexpected event. This study assesses the resistance capacity of local communities against tsunami inundation by continuous increase in tsunami intensity. The analysis shows the tsunami magnitude which changes the stage of disaster response referring to loss of shelter capacities in the administrative side and the potentially vulnerable and high risk areas against tsunami inundations in the residence side.

DOI： 10.2208/kaigan.70.I_1326

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

There are a lot of researches about momentum exchanges at sea surface which focus on the relationship between wind speed and roughness. Although such researches continue, none of them has explained the roughness under all sea condition. This study evaluates the impact of bulk formulas including wave information on the typhoon simulation using observed results in ITOP. Air side roughness including wave information makes the heat flux from sea to strengthen and influences the wind profile even in the upper air. Typhoon is not affected the air side roughness. The bulk formulas of sea side roughness and TKE flux which is based on wave information estimate smaller current speed and TKE than the formulas based on wind.

DOI： 10.2208/kaigan.70.I_461

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

Although a real-time tsunami prediction method which uses observed tsunami waveform as input data for an inversion analysis is effective for non-structural measures, the method needs to wait several-ten-minutes for observed data acquirement. To solve this disadvantage, authors propose the hybrid method which uses not only observed tsunami waveforms but also source rupture process estimated from strong motion seismogram. Unit tsunami source grids for inputs of inversion analysis are selected considering source rupture information. Restraint condition between neighbor unit source grids is employed to estimate the initial tsunami displacement smooth. Effectiveness of additional observation points are discussed to improve the accuracy and reduce the length of input data. The appropriate combination of source rupture process, restraint condition, and additional observation points are effective to improve the accuracy of the real-time tsunami prediction in Tohoku coasts.

DOI： 10.2208/kaigan.70.I_396

CiNii Books

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その他リンク： https://jlc.jst.go.jp/DN/JALC/10041329527?from=CiNii

記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

Future projection of ocean wave climate was conducted by a spectral wave model using winds from multi-SST and multi-model ensemble experiments of global climate model (MRI-AGCM3.2H). Future changes of extreme waves were investiged under conditions of tropical cyclone (TC) and Non-TC separately. The spatial distribution of future changes in Non-TC extreme waves in global scale were similar to that of mean waves shown in IPCC-AR5. The 10-yr return wave heights under TC condition in the Western North Pacific showed increase or decrease by 4m for different regions. The spatial distribution can be explained by eastward shift of TC.

DOI： 10.2208/kaigan.70.I_1266

CiNii Books

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その他リンク： https://jlc.jst.go.jp/DN/JALC/10041328483?from=CiNii

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：ICE Publishing  

The present study first proposes a random wave runup formula for seawalls installed near shoreline with complex cross section. Then a prediction formula of wave overtopping is developed from the original model of Hedges and Reis (1998) to the case of seawalls near the shoreline including on land. The present formula is used to estimate wave overtopping discharge seen at Ashizaki Nyuzen-machi coastal disaster in 2008 of Toyama Prefecture, Japan, and compared with other existing formulae.

DOI： 10.1680/fsts.59757.0432

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ASCE-AMER SOC CIVIL ENGINEERS  

The current study proposes prediction formulas both for random wave runup and mean overtopping discharge at seawalls constructed on land or in very shallow water. Although several existing formulas for runup and overtopping use the incident wave characteristics at the toes of seawalls, this study adopts the equivalent deepwater wave characteristics and an imaginary seawall slope for easy application of the formulas, especially in relation to seawalls constructed on land. The prediction formulas for overtopping use the predicted runup values. For the wave runup prediction formulas two sets of experimental data are used; i.e., a new set of data and the data obtained in a previous study. For the wave overtopping prediction formulas, the experimental data measured in a previous study are used. Comparisons with measurements show good performances of both new prediction methods. (C) 2013 American Society of Civil Engineers.

DOI： 10.1061/(ASCE)WW.1943-5460.0000199

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ASCE-AMER SOC CIVIL ENGINEERS  

In Japan, the probability of a Tokai, Tonankai, and Nankai earthquake occurring in the early 21st century is high. Given this likelihood, estimating the resulting tsunami in real time is desirable. This study details an inversion method for real-time tsunami predictions using only observed offshore tsunami data. Numerical experiments demonstrate that (1) the tsunami wave source is estimated fairly well using the inversion method compared with the initial sea surface displacement calculated from the earthquake fault model; (2) the tsunami profiles are predicted with great accuracy at coastal locations of interest; and (3) the profiles are accurately and easily updated using a longer duration of observed tsunami data after an earthquake. This study also investigates techniques to improve the accuracy of the forecasts: screening optimal locations for offshore global positioning system (GPS) buoys, using a longer period of observation data, and decreasing the duration of the tsunami prediction. These techniques illustrate the practical application of this method for tsunami forecasting. DOI: 10.1061/(ASCE)WW.1943-5460.0000159. (C) 2013 American Society of Civil Engineers.

DOI： 10.1061/(ASCE)WW.1943-5460.0000159

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1193/1.4000122

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：EARTHQUAKE ENGINEERING RESEARCH INST  

At 14:46 local time on 11 March 2011, a magnitude 9.0 earthquake occurred off the coast of northeast Japan. The very large local tsunami heights and damage to coastal structures and other civil infrastructure were strongly dependent on the location. To verify the effectiveness of several types of tsunami protection strategies, we analyzed three typical areas from the Sanriku ria coast. Detailed survey data are shown with photographs and are discussed with regard to severity of damage and tsunami event. The roles of offshore tsunami breakwaters and coastal forests are discussed for severe tsunami, which exceeds 10 m near the coast. The survey observations and results from numerical calculations clearly indicate the reduction of tsunami damage due to an offshore barrier in Kamaishi Bay.

DOI： 10.1193/1.4000118

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Japan Society of Civil Engineers  

DOI： 10.2208/kaigan.69.i_126

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：WORLD SCIENTIFIC PUBL CO PTE LTD  

The shape of blocks favorable for their stability against wave action was analyzed from the viewpoint of "space occupancy ratio in a cuboid" for existing blocks. A new high stability block was proposed in this study, which has the shape with three legs at both ends of the axis. Hydraulic experiments were conducted to examine the block stability. A stability number formula was determined from the experimental results. Required weight of the proposed high stability block against design waves is almost the same as a typical high stability block due to the effective interlocking between the blocks. Proposed high stability block is able to decrease the required number and contribute to the cost reduction since the porosity among the blocks becomes large.

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：日本語   出版者・発行元：土木学会  

CiNii Books

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

本研究は，粘り強い防波堤の設計法の確立に向けた基礎的な検討として，ケーソン式混成堤を対象に水理模型実験を実施し，現状断面と補強対策断面の比較を通じて補強効果を調べることを目的とした．実験では，津波（半周期の正弦波で模擬）を作用させて，水位や作用波圧，ケーソンの変形量を計測した．実験結果の検討から，腹付マウンド補強を実施した場合，補強幅を広げると補強効果が上がるが，その場合高さも確保する必要があることがわかった．また，堤体の滑動・転倒に対する安全率が同じであっても，作用津波と堤体諸元の関係によって移動量として現れる防波堤の粘り強さは異なることがわかった．補強の有無や補強材の違いによって安全率と移動量は異なるが，堤体の滑動安全率によって移動量を推定できる近似曲線を提案した．

DOI： 10.2208/jscejoe.69.I_473

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

本研究は，消波ブロック被覆堤を対象として，モンテカルロシミュレーションによる消波工のライフサイクルコスト(LCC)の算定において，高波発生回数が及ぼす影響を検討したものである．LCCとして初期建設費と供用期間の補修費を計上し，高波発生回数を年1回とする場合と，波浪観測資料にもとづく統計的特性を考慮して与える場合の2通りの計算を行った．日本沿岸の4地点での高波資料を解析した結果，年間の高波発生回数はポアソン分布で近似できることが示され，LCCの算定においてポアソン乱数で高波発生回数を与えた．結果として，LCCを最小とする消波ブロック径が高波発生回数の与え方によって異なったのは1地点のみであったが，補修費の変動性については差異が生じ，高波発生回数の及ぼす影響を考慮する必要性が示された．

DOI： 10.2208/jscejoe.69.I_173

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J-GLOBAL

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掲載種別：研究論文（学術雑誌）  

DOI： 10.2208/kaigan.69.i_511

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Elsevier Ltd  

Settlement of wave-dissipating blocks in front of caisson is caused by displacement and breakage of blocks directly by wave action and also by sliding of the caisson by wave force. The settlement of blocks, caisson sliding and wave pressure are mutually correlated. The present study has developed a stability analysis method for a composite breakwater with wave-dissipating blocks under the circumstances of climate change effect as seen in sea level rise and increase in storm surges and waves. It is found that the changes of expected caisson sliding distance and necessary caisson width, determined from the allowable excess probabilities for three prescribed sliding distances, against the weight of wave-dissipating block have a tendency to be maximum at certain block weight when repairing of damaged blocks is not done
on the other hand, if repairing is done every time after reaching 5% damage level of the total section, the changes of caisson sliding distance and necessary caisson width against the block weight show monotonous decrease. The effects of climate change on the sliding distance and necessary width are found to make those values larger by 10-60% than those calculated by constant external forces given from the present climate conditions. © 2012 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.oceaneng.2012.12.037

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Elsevier Ltd  

This study analyzes future changes in average upper ocean physics such as sea level rise, sea surface winds and ocean wave heights by using a climate data set combining IPCC (2007) results and the latest high-resolution atmospheric general circulation model results from the Meteorological Research Institute, Japan. Ocean wave height Hs is statistically projected by using multi-model ensemble method based on an empirical formula as a function of sea surface winds. The ensemble means and the standard deviations of upper ocean physics, which can be used in coastal and ocean engineering, are projected for the period between 2000 and 2100. The magnitude of the ratio of future changes in Hs to the value in the present climate is at most ±15%, which exceeds the projected changes in sea surface pressure and surface wind speed, U10. A large uncertainty in the projected Hs can be observed around the Equator and in the Antarctic Ocean. The synoptic scale of atmospheric pressure distribution is found to be important for estimating and understanding the future changes in sea level rise, U10 and H s. © 2013 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.oceaneng.2013.02.016

Scopus

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：WORLD SCIENTIFIC PUBL CO PTE LTD  

The field survey results obtained by the team of authors in the north of Miyagi Prefecture between April 1 and 6, 2011 are summarized referring to a part of the survey results by other teams of the 2011 Tohoku Earthquake Tsunami Joint Survey Group. The inundation height above sea level was measured using a laser range finder with a reflection prism. The inundation height was generally larger at bay heads, as well as promontory tips, except several points, which were sheltered by a peninsula or had a tapering area. The tsunamis reached inland far away from the sea along valleys and rivers. Not only steel frame buildings but also many reinforced concrete buildings were collapsed in Onagawa Town. According to the numerical results, the first of tsunamis from the west coast and the second of tsunamis from the east coast should come together in Utatsusaki Peninsula, which is consistent with the interviews to survivors.

DOI： 10.1142/S0578563412500076

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

洋上風力発電施設のオペレーション，タンカーの港への入港判断，フェリーの運航判断，マリンレジャーの計画等に利用可能な風と波浪の予測情報の予測・表示システムを開発した．予測情報は，リードタイム，予測期間，利用目的によって予測値の利用価値が決まる．洋上風力発電施設のオペレーション・アンド・メンテナンスの工程計画には1週間先，ケーソン据付等の港湾・海洋工事に対しては3～4日先，海水浴，サーフィン，ヨット等の海浜・海域利用では2～3日先の情報が必要であるので，それらに応じた予測情報を得られるようにしたシステム開発を行った．

DOI： 10.2208/jscejoe.68.I_1204

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

本研究は，地球温暖化に伴って変化すると予測される，設計供用期間内の外力変化を考慮した防波堤の滑動量解析を行い，沿岸外力特性の変化が消波ブロック被覆堤の滑動安定性に及ぼす影響を検討したものである．地球温暖化に伴う海面上昇や高潮偏差の増大，来襲波浪の増大を考慮した消波ブロック被覆堤の滑動量解析を実施した結果，本研究で想定した将来条件では，地球温暖化を考慮すると期待滑動量が100～350%増加した．また，地球温暖化による期待滑動量と必要堤体幅への影響は，想定される波高変化だけでなく，水深波高比に大きく依存することがわかった．特に大水深域に防波堤を設置する場合，設計供用期間中の沿岸外力変化の影響が大きく表れることがわかった．

DOI： 10.2208/jscejoe.68.I_276

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

地震調査研究推進本部によると，東海・東南海・南海地震が同時発生した場合には，マグニチュード<i>M_w</i>は8.7になると推定されている．本研究では，中央防災会議(2003)の想定津波波源域を用い，三連動地震の影響地域のうち，和歌山県を対象地域として，すべり量を変化させて想定を超えた場合に浸水深や浸水範囲がどのように変化するかを，数値シミュレーションによって調べた．その結果，最大浸水面積の変化は場所に大きく依存し，県中部と南部では，<i>M_w</i>の変化にほぼ比例して増大するが，北部の和歌山市周辺では，標高の低い場所が多いために，<i>M_w</i>が大きくなると浸水範囲が急拡することがわかった．<i>M_w</i>9.0の場合の和歌山市周辺を除いて，浸水深と標高にはおおよそ反比例の関係がみられた．

DOI： 10.2208/jscejoe.68.I_156

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記述言語：日本語   出版者・発行元：土木学会  

CiNii Books

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記述言語：日本語   出版者・発行元：土木学会  

CiNii Books

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記述言語：英語  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER GEOPHYSICAL UNION  

At 14: 46 local time on March 11, 2011, a magnitude 9.0 earthquake occurred off the coast of northeast Japan. This earthquake generated a tsunami that struck Japan as well as various locations around the Pacific Ocean. With the participation of researchers from throughout Japan, joint research groups conducted a tsunami survey along a 2000 km stretch of the Japanese coast. More than 5300 locations have been surveyed to date, generating the largest tsunami survey dataset in the world. On the Sendai Plain, the maximum inundation height was 19.5 m, and the tsunami bore propagated more than 5 km inland. Along the ria coast from about 50 to 200 km north of Sendai, the narrow bays focused the tsunami waves, generating the largest inundation heights and run-ups. The survey data clearly show a regional dependence of tsunami characteristics. Citation: Mori, N., T. Takahashi, T. Yasuda, and H. Yanagisawa (2011), Survey of 2011 Tohoku earthquake tsunami inundation and run-up, Geophys. Res. Lett., 38, L00G14, doi:10.1029/2011GL049210.

DOI： 10.1029/2011GL049210

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ASCE-AMER SOC CIVIL ENGINEERS  

This study examined the validity of using an artificial neural network (ANN) to predict tsunami water levels at several locations in Osaka Bay. The metropolitan areas of Osaka Bay have short warning times for tsunamis; a real-time tsunami forecast will allow for improved evacuation plans and will reduce the effect of these coastal disasters. Different tsunami conditions changing the relative strength of the asperities and background sources, such as fault displacement, fault length, fault width, fault slope, depth from sea bottom, and strike, were used for training the ANN; the data sets were generated by applying the nonlinear shallow water wave equations assuming different earthquake fault models. The linear activation function produced optimal results for the ANN output units, and the tangent-sigmoid function yielded good results for the ANN hidden layer units. The Levenberg-Marquardt method with Bayesian regulation was employed for the training of the ANN. Output from the trained ANN was the preliminary and secondary tsunami waves; these ANN output data agreed well with numerically obtained tsunami simulation results. DOI: 10.1061/(ASCE)WW.1943-5460.0000092. (C) 2011 American Society of Civil Engineers.

DOI： 10.1061/(ASCE)WW.1943-5460.0000092

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記述言語：日本語   出版者・発行元：土木学会  

CiNii Books

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記述言語：日本語   出版者・発行元：土木学会  

CiNii Books

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：土木学会  

CiNii Books

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掲載種別：研究論文（学術雑誌）   出版者・発行元：Japan Society of Civil Engineers  

DOI： 10.2208/kaigan.67.i_1181

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

Wave set-up in storm surges is studied using a numerical model for coasts in Tosa Bay, Japan, open to the Pacific Ocean. Simulation models employing only atmospheric pressures and winds as external forces are unable to properly simulate open coast storm surge heights, such as those due to Typhoon Anita (1970). However, the present study shows that a numerical model incorporating wave-induced radiation stresses, as well as wind stresses and pressure gradients, is able to account for the open coast surge heights. There is a maximum contribution of 40% by the radiation stresses to the peak sea level rises. This study also evaluates the effects of the tides; including the tides improves the agreement between the predicted water surface elevations and the observations. The difference in predictions between one-way coupling from wave to surge models and two-way coupling of the surge and wave models is found to be small. (C) 2010 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.coastaleng.2010.02.004

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記述言語：英語  

DOI： 10.1061/(ASCE)0733-950X(2008)134:3(187)

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記述言語：英語   出版者・発行元：Japan Society of Civil Engineers  

A model of predicting coastal currents under non-stationary meteorological and wave conditions is eveloped. The current prediction model is composed of meteorological reanalysis data, a meso-scale weather prediction model and a coupling wave and surge model. The model is applied to the Joetsu Coast for predicting coastal currents and the predictions are compared with observations. The prediction model is also extended to statistically modeled time series of winds and waves. It has been found that coastal currents calculated by the prediction model depend strongly on ocean wind.

DOI： 10.2208/kaigan.66.321

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その他リンク： https://jlc.jst.go.jp/DN/JALC/00358854027?from=CiNii

記述言語：英語   出版者・発行元：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

This study presents a stochastic typhoon model (STM) for estimating the characteristics of typhoons in the present and future climate conditions. Differences between statistical characteristics of present and future typhoons were estimated from projections by an Atmospheric General Circulation Model (AGCM) under a climate change scenario and are taken into account in the stochastic modeling of future typhoons as a climate change signal. From the STM results which utilize the Monte Carlo simulation, it was found that the frequency of typhoon landfall in Japan, especially in three major bay areas, will decrease and the mean value of typhoon central atmospheric pressure will not change significantly. An important point is that the arrival probability of stronger typhoons will increase in the future climate scenario.<br>

DOI： 10.3178/HRL.4.65

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記述言語：英語   出版者・発行元：水文・水資源学会  

The influence of global climate change due to greenhouse effects on the earth&rsquo;s environment will require impact assessment, mitigation and adaptation strategies for the future of our society. This study predicts future ocean wave climate in comparison with present wave climate based on the atmospheric general circulation model and global wave model. The annual averaged and extreme sea surface winds and waves are analyzed in detail. There are clear regional dependences of both annual average and also extreme wave height changes from present to future climates. The wave heights of future climate will increase at both middle latitudes and also in the Antarctic Ocean, with a decrease at the equator.<br>

DOI： 10.3178/HRL.4.15

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記述言語：英語   出版者・発行元：Japan Society of Civil Engineers  

The present study validates real-time wave prediction by using wind forcing from hourly analysis GPV during the typhoon season of Japan. Large variations in weather fields occurring in typhoon events provide an opportunity to assess the quality of forecasts. Observed data at 16 NOWPHAS wave gauge stations were used to evaluate predictions during the typhoon season. Deterministic statistic error indices showed that real-time predictions give good results. In addition, probabilistic statistic error indices that can evaluate errors in detail also showed that the correspondence between predictions and observations is good.

DOI： 10.2208/kaigan.66.161

CiNii Books

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その他リンク： https://jlc.jst.go.jp/DN/JALC/00358853679?from=CiNii

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：WORLD SCIENTIFIC PUBL CO PTE LTD  

The study investigates abnormal surges occurred with time lags to typhoon's peak at west coasts along the Sea of Japan To examine the abnormal Surge due to Typhoon Songda in 2004 the Surge simulations are carried out using different input forces of winds and atmospheric pressures The response of abnormal surges to the effects of terrain and meteorological fields is also examined The results indicate that using output from meso-scale weather prediction model successfully reproduces the abnormal surges occurred with time lags of 15 hours.

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掲載種別：研究論文（学術雑誌）   出版者・発行元：Japan Society of Civil Engineers  

DOI： 10.2208/kaigan.66.1231

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記述言語：英語   出版者・発行元：Japan Society of Civil Engineers  

Since major driving forces of storm surge are pressure depressions and wind stresses, a set of depth integrated equations is widely used for storm surge simulations. However, there are several phenomena which should be take into consideration additionally. This study estimates effects of wave radiation stress, vertical mixing and turbulent flux for 3D storm surge model. The effects of revised radiation stresses in the sigma coordinate and wave directional spread are evaluated into the numerical model. The numerical results give significant influences of the wave radiation stress and the turbulent flux on the surface elevation and the current in the stormy condition.

DOI： 10.2208/kaigan.66.306

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記述言語：英語   出版者・発行元：Japan Society of Civil Engineers  

The height of seawall is determined based on allowable wave overtopping rate or wave runup height for the design of surge and wave prevention facilities. Although a design method based on wave overtopping rate takes into account of wave randomness, a design method based on wave runup height does not consider the wave randomness but uses equations and figures obtained from regular waves. Therefore, a unified prediction formula for random wave overtopping and runup is required for establishing the design scheme of seawalls. This study proposes prediction formula for random wave overtopping discharge including wave runup for seawalls with composite cross section installed near shoreline.

DOI： 10.2208/kaigan.66.926

CiNii Books

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その他リンク： https://jlc.jst.go.jp/DN/JALC/00358855369?from=CiNii

記述言語：日本語   出版者・発行元：日本沿岸域学会  

CiNii Books

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記述言語：英語   出版者・発行元：Japan Society of Civil Engineers  

A flapgate breakwater is a new type structure that usually lies down on the seabed and rises up as a seawall with its buoyancy when tsunami or storm surge occurs. In our previous studies, the characteristics of the flapgate motion and wave pressure were clarified through a series of hydraulic model experiments, and a numerical model that can deal with fluid-structure interactions for the flapgate employing the overset grid method and the level set method was developed for a solitary wave representing a tsunami. In this study, the numerical model was extended to the cases of flapgate motion analysis against periodic waves, and simulation results were compared with experimental ones. It is shown that the numerical model gives accurate predictions of flapgate motions and provides useful information for the design of different size flapgates and wave conditions.

DOI： 10.2208/kaigan.66.811

CiNii Books

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その他リンク： https://jlc.jst.go.jp/DN/JALC/00358855116?from=CiNii

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記述言語：英語   出版者・発行元：公益社団法人 土木学会  

The present study examines the prediction accuracy effects of 4-dimensional data assimilation (nudging) and nesting schemes of the Weather Research and Forecasting model (WRF) on the storm surges. Applying both nudging and nesting in the WRF simulation enabled us to predict successfully not only the barometric depression and increase of wind speed around a typhoon route, but also the meteorological field of surrounded area. It has been found that the use of WRF outputs applying both with nudging and nesting would give accurate predicting power for both maximum level and phase of tidal elevation in the storm surge simulations.

DOI： 10.2208/kaigan.65.381

CiNii Books

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その他リンク： https://jlc.jst.go.jp/DN/JALC/00347681924?from=CiNii

記述言語：英語   出版者・発行元：公益社団法人 土木学会  

At Sakai-Minato port around west coast of the Sea of Japan, abnormal storm surges have been measured with timing lags of 15 hours after landfall of typhoons. The present study examines the abnormal storm surges due to Typhoon 0314 and 0418 using the SuWAT (Surge-Wave-Tide coupled model) in different meteorological conditions by the WRF (Weather Research and Forecasting model) and an empirical typhoon model proposed by Fujii and Mitsuta. The results of simulations indicate that the abnormal surges forced by the WRF outputs show good agreement with the measurements. Also, this study describes mechanism why the abnormal surges with time lag are generated due to typhoons at the Sakai-Minato Port.

DOI： 10.2208/kaigan.65.376

CiNii Books

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その他リンク： https://jlc.jst.go.jp/DN/JALC/00347681917?from=CiNii

記述言語：日本語   出版者・発行元：土木学会  

CiNii Books

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記述言語：英語   出版者・発行元：公益社団法人 土木学会  

A flap gate breakwater is a new type structure for coastal disaster reduction; the breakwater usually lies down on a seabed and rises up through sea surface with buoyancy when tsunami or storm surge occurs. In past studies, it has been confirmed that the flap gate breakwater has capabilities against tsunamis. The characteristics of wave pressure acting on flap gate are different from those on a fixed gate and a breakwater since the flap gate moves according to acting waves or tsunamis. The present study examined the characteristics of wave pressure acting on the flap gate by hydraulic experiments using monochromatic waves and tsunamis. It was confirmed that the gate motion and wave pressure were closely related, and wave pressure was reduced by employing fluid resistance plates.

DOI： 10.2208/kaigan.65.806

CiNii Books

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その他リンク： https://jlc.jst.go.jp/DN/JALC/00347682778?from=CiNii

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：WORLD SCIENTIFIC PUBL CO PTE LTD  

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記述言語：英語   出版者・発行元：公益社団法人 土木学会  

Stochastic typhoon simulation, that is the combination of the Monte Carlo simulation on typhoon parameters, the storm surge simulation with the parameters, and the extreme-value analysis on the storm surges, is one of useful tools in the probabilistic discussion on the current design storm water level for coastal defense. This paper compares the extreme storm surges on the Pacific coast from Kyushu to Kanto District, Japan, with two empirical parametric typhoon wind field models, two sea surface drag coefficients for high wind speed, and two assumptions of future typhoon change. The result shows that the extreme storm surge is very sensitive to the sea surface drag coefficient for high wind speed and that one of the assumptions gives larger extreme storm surges in some of the coast and smaller in others.

DOI： 10.2208/kaigan.65.1256

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記述言語：英語   出版者・発行元：Japan Society of Civil Engineers  

A series of data set of ocean wave records from the Pacific Ocean and the Sea of Japan is analyzed for understanding freak wave characteristics in lights of wave height statistics, frequency and directional spectrum parameters, and nonlinear statistical parameters. In addition, measured maximum wave heights are compared with predicted ones by a nonlinear wave theory, and the relation of freak wave occurrence with weather condition is made. It was found that observed data shows a weak correlation between maximum wave heights and kurtosis of free surface elevation and that freak waves at peak of storm are observed under migratory low atmospheric pressures.

DOI： 10.2208/kaigan.65.141

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：WORLD SCIENTIFIC PUBL CO PTE LTD  

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記述言語：英語   出版者・発行元：公益社団法人 土木学会  

Wave climate was investigated for impact assessment and adaptation strategy for coastal hazard area. Related studies show regional dependence; in some regions wave heights increase these 30 years and in some areas decrease. This study examined a long-term variability of annual large waves, such as maximum, top three averaged and top five averaged waves, along coasts of the Sea of Japan using observed wave data. When waves generated by winter monsoon pattern were considered, the wave heights increased in northern area of Japan. The relation between the variations of maximum wave heights and three meteorological indeces was examined; however, there was no clear correspondence between them.

DOI： 10.2208/kaigan.65.1251

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：WORLD SCIENTIFIC PUBL CO PTE LTD  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：WORLD SCIENTIFIC PUBL CO PTE LTD  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCI LTD  

This study examines the effects of tides on surges, wave setups and waves, in terms of tidal amplitudes and phases, by using a coupled numerical model of Surge, WAve and Tide (called as SuWAT). The SuWAT model, composed of depth integrated nonlinear shallow water equations and Simulating WAves Nearshore (SWAN) model, is able to simultaneously run with an arbitrary number of nested domains by using the Message Passing Interface. The results for an idealized case indicate that surge and wave setup are increased in the phase of low water and decreased in the high water phase; on the other hand, waves change in a reverse manner. Such changes are enhanced by large tidal variations. The conventional method (e.g., surge plus tide independently) has the possibility of overestimation for the total water level. The hindcast results for Typhoon Ewiniar in 2006 show that the run with tides is more accurate 10% than that without tides in coastal areas of Korea. The nested scheme improves the accuracy up to 40% for the prediction of water levels in the simulations. It is shown that the present coupled model, SuWAT, is capable of predicting both water levels and waves under storm events with reasonable accuracy against the observations. (C) 2009 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.apor.2009.02.003

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出版者・発行元：Japan Society of Civil Engineers  

This study developed a real-time wave prediction system by using SWAN (Simulating WAves Nearshore) with the data of hourly analyzed atmospheric GPV (Grid Point Value). The validity of this system was carried out by comparing the predictions with observations from NOWPHAS (Nationwide Ocean Wave information network for Ports and HArbourS) during one month of December, 2007. The predicted wave heights and periods well corresponded to the observed ones. By using this system, wave situations at present and short-term future can be estimated for locations where there are no wave observation equipments.

DOI： 10.2208/proce1989.55.186

CiNii Books

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その他リンク： https://jlc.jst.go.jp/DN/JALC/00368614666?from=CiNii

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

A set of experiments was conducted to examine the stability of new type of wave dissipating blocks. It was confirmed from the experimental results that offshore wave steepness influences the stability of blocks. The parameters of stability number formula were derived with classification of wave steepness. Required weight of new block against a design wave can be reduced to 90 percent compared to a typical standard block because the stability is being improved. The wave steepness relates deeply to the breaker type, and wave steepness' effect should not be neglected in the stability estimation of blocks. In order to separate the effects of wave steepness and wave breaking, it had better to conduct the experiments with flat bottom condition for further investigation of blocks' stability.

DOI： 10.2208/prooe.24.519

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

Geometrical coastal line in big maritime cities is usually complex, since there are many reclaimed lands, many rivers and canals flowing into the sea. For such complex sea area, fine mesh scale is required for the estimation of tsunami propagation and deformation, resulting in increase in the computational time and cost. In this study, a new calculation method, called the Cartesian cutcell method, is used for predicting tsunami propagations and the numerical results are compared with the experimental observations. In the Cartesian cutcell method, the finer mesh is not required even for the complex geometrical coastal shape.

DOI： 10.2208/prooe.24.81

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記述言語：日本語   出版者・発行元：土木学会  

CiNii Books

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出版者・発行元：Japan Society of Civil Engineers  

A modeling method of long-term time series of waves and winds for evaluation of beach profile change was proposed. Statistical properties of parameters, representing storm waves, were analyzed and theoretical distributions were obtained together with correlations between those parameters. To check the uniformity of waves, meteorological and wave simulations were carried out. Those predictions were compared with the observations at the Naoetsu Port, and found to be well agreed each other. It was concluded that since spatial distribution of waves is uniform along the Joetsu Coast, the statistical variables can be given as input parameters for the concerned area.

DOI： 10.2208/proce1989.55.426

CiNii Books

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その他リンク： https://jlc.jst.go.jp/DN/JALC/00368615199?from=CiNii

記述言語：日本語   出版者・発行元：土木学会  

DOI： 10.2208/proce1989.55.156

CiNii Books

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出版者・発行元：Japan Society of Civil Engineers  

High wave with long wave period, which is known by local residents as "Yorimawari-Nami", hit the east coast of Toyama Prefecture on February 24, 2008. The high wave, in particular, caused huge human and property damages in Ashisaki district of Nyuzen town. The purpose of this study is, at first, to examine coastal damages induced by the swelllike wave throughout filed surveys. The characteristics of high wave deformation, wave overtopping of a gentle-slop type revetment and inundation flow in the residential area are, furthermore, discussed by performing wave hindcasting with a GFS-WRF-SWAN coupled model and numerical simulation on wave overtopping of the revetment in Ashisaki district using a two-dimensional numerical wave flume "CADMAS-SURF".

DOI： 10.2208/proce1989.55.151

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出版者・発行元：Japan Society of Civil Engineers  

This paper uses reliability analysis to estimate the failure probabilities associated with wave overtopping of both sloping and vertical seawalls. Failure probabilities are obtained for different freeboards and permissible overtopping rates, using Monte Carlo simulation for calculations at Level III and the First Order Reliability Method for Level II calculations. The sensitivity of the performance function to the various external random variables is also investigated inorder to establish the relative importance of these variables in influencing the failure probabilities.

DOI： 10.2208/proce1989.54.891

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出版者・発行元：Japan Society of Civil Engineers  

This study examines the validity to use an artificial neural network (ANN) for the prediction of tsunami magnitudes at several locations in the Osaka Bay by using observed water surface elavations of 20 minumites, at the tower of Shirahama Oceanographic Observatory. The tsunami data used as training and test data for ANN were simulated for different fault models considering tsunami source non-uniformity. The linear activation function was found to be a good choice for output units and the tangent sigmoid function for hidden layer's units. For the training of ANN the Levenberg-Marquardt method with Bayesian regulation were employed. Outputs from the trained network such as the first and the second sea surface falls and rises agreed well with the results of tsunami simulations at each location and all five locations.

DOI： 10.2208/proce1989.54.201

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出版者・発行元：Japan Society of Civil Engineers  

The present paper has discussed how to improve our real-time tsunami prediction method by the inverse analysis of tsunami profile observed at offshore points. The inverse analysis of the offshore tsunami data estimates the initial displacements of water surface in the segmented tsunami sources. The estimated initial displacements predict tsunami profiles at inshore points of interests. Our prediction method is tried to improve by the introduction of correlation factors with surrounding segmented sources, the supplement of another observation point, or the employment of wider segmented source area. The paper also confirms that the real-time prediction can be applied to predict the tsunami at Shimotsu Port in Wakayama Prefecture as well as in Osaka Bay.

DOI： 10.2208/proce1989.54.196

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

Tokai, Tonankai and Nankai earthquakes are predicted to generate great tsunamis which will attack the Pacific Coasts. The tsunami will arrive at the coasts within ten minutes after the shaking, and its height reaches 5m or more. To save lives of residents in these affected areas from the tsunami, a shelter tower is newly designed, and it begins to be constructed by the local governments. A hydraulic experiment is performed to check the stability of the shelter tower at exertion of the tsunami. It is confirmed that if there are no debris, the tower is enough stable because tsunami force is smaller than shear strength of the column connections. On the other hand, if the force is increased by debris, overturning moment becomes much larger than the resistant moment by the tower weight without considering the pullout resistance force of the columns. Presuming of tsunami force which acted on land structures such as the tsunami shelter was proposed by using newly derived tsunami velocity equation and the drag coefficient of the structures.

DOI： 10.2208/prooe.23.99

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

The present study examines the soliton fission process of tsunami propagating over reef shallow water coast by hydraulic experiments. The effects of water depth above the reef, tsunami amplitude and period are investigated. In addition to the experiments, two different kinds of numerical models are employed in order to know how accurately the models can reproduce the process of tsunami transformation such as the occurrence of fission, amplitude, number of soliton waves and phase celerity propagating over the reef. It was found that even if the tsunami amplitude and period are the same, the transformation process of first water-level-rising tsunami is different from that of first-falling tsunami and that there are differences between experimental transformations and numerically obtained transformations generally.

DOI： 10.2208/prooe.23.165

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出版者・発行元：Japan Society of Civil Engineers  

A tide-surge-wave coupling model has been developed by employing a nesting scheme to be simultaneously parallelized by MPI. By using this model, effectso flarge tidal variation on storm surges and wave set-up were assessed for the case of simplified bathymetry and the western coastal sea of Korea. The effect of large tidal variation is confirmed to reduce the magnitudes of the storm surges and set-ups. Especiallyt, he effect is a predominant factor for the occurrence of severe disaster due to typhoons in the sea where the large tidal variation takes place such as the western coastal sea of Korea.

DOI： 10.2208/proce1989.54.276

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：WORLD SCIENTIFIC PUBL CO PTE LTD  

The Indian Ocean Tsunami on 26 December 2004 affected Sri Lanka, which is located 1,700 km from the epicenter. A field investigation was conducted along the southwest coast of Sri Lanka to measure tsunami trace heights, investigate the damage, and obtain correct information on the tsunami. The results of the field survey showed that the tsunami arrived on the Southwest coasts two and a half hours or more after the earthquake. The average tsunami height was 5 m along the southwest coast and tsunami trace heights of 10 in were found call v. The tsunami destroyed a number of wooden and brick houses, damaged port and harbor facilities and coastal railways, washed away many vessels, and scoured the foundations of coastal structures. The port and harbor facilities such as the breakwaters, and rigid coastal houses continuing along the coast reduced the tsunami and lessened the damage that it caused.

DOI： 10.1142/S0578563406001362

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DOI： 10.20965/jdr.2006.p0148

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記述言語：日本語   出版者・発行元：日本沿岸域学会  

CiNii Books

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

本研究は, コスト削減の観点から, 護岸被覆材 (特に消波ブロック) のライフサイクルコスト (以下, LCCと略す) を最小化する最適設計手法を提案するものである. 本手法では, LCCとして初期建設費用および耐用年数間の補修費用のみを対象とし, 補修費用については高橋ら (1998) が提案した被災度の経験式を用いて算出している. 本手法による検討結果では, 要修復基準である要補修被災度を大きくとると最適重量は軽くなった. また, 水深が浅い場合には, ハドソン公式で求めた重量よりも重いブロックが最適重量となるが, 水深が深い場合には, ハドソン公式で求めた重量とほぼ同程度のものが最適重量となった.

DOI： 10.2208/proce1989.53.856

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

A big difference between the Andaman Sea coast and the coasts in the western countries of the Indian Ocean was found in damage state caused by the Indian Ocean Tsunami. It is thought that geographical features of the coastal cross-shore section affect the characteristics of the tsunami deformation and the damage situation of the coastal structures. In this paper, the model experiments were conducted to clarify the difference of deformation, breaking, runup or pressure of tsunami by the characteristic of the coastal cross section. The wave steepness and water depth on the reef are closely related to generation and development of dispersive solitons, and it is clarified that the impulsive breaking wave force takes place at the breaking of individual soliton. Tanimoto's empirical formula can be applied to estimate the wave force of tsunami on coastal structures when the dispersive solitons almost disappear due to these breaking or no dispersive solitons occur.

DOI： 10.2208/prooe.22.529

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

The present design procedures for the breakwater with footing ignore a wave pressure acting on the footing under the assumption that the compressive force on the upper face of the footing can be cancelled by the uplift force on the bottom face of the footing. This assumption is acceptable, but the experiments have confirmed that the compressive force becomes much lager for the case of long footing than the uplift force and works to stabilize the breakwater. We have proposed two empirical formulas for the distributions of uplift and compressive pressures. However, the validity of the formulas was not confirmed for random wave experiments. The present paper describes the confirmation of their validity thorough the experiments in random wave and numerical simulations. The empirical formulas are slightly improved.

DOI： 10.2208/prooe.22.319

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

3種類の気象データ (NARR, GFS, FNL), 3種類の風から波へのエネルギー伝達モデル (Komenら, Janssen, Lalbeharryら) および計算対象周波数領域を2種類としてハリケーン・カトリーナによる高波追算を行い, 観測結果と比較して, 1) 空間・時間分解能がよいNARRを用いても推算結果は観測結果をうまく再現できない, 2) GFSとFNLは同程度の結果が得られる, 3) エネルギー伝達モデルはKomenらが全般的に良く, Janssenでは観測結果に比べて小さくなる, 4) 最も大きな有義波高が観測された地点で再現性が良かったのは, Lalbeharryらのモデルを用いた場合であることを示した.

DOI： 10.2208/proce1989.53.421

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

Hurricane Katrinaによる高潮, 高波被害の実態を調査し, 日本の高潮, 高波被害対策に資する教訓を得た. 被災の全体的な特徴としては広域性 (延長300km以上に渡る被災, 州を越えての長距離避難), 甚大性 (死者1, 300人余り, 膨大な数の避難者, 都市機能の停止), 長期性 (今も避難を余儀なくされている多数の人々, 都市の衰退への動き) が挙げられる. 自治体ごとに被災時の対応が異なったため, 住民が避難していなかった所と前夜に住民が避難していた所では被害の出現, 復興のプロセスも異なっていた. このような被害の多様性を分析した上で, 防災計画を地域の多様性を前提にして練り上げていく必要がある.

DOI： 10.2208/proce1989.53.401

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

地震発生時の津波を推定する際, 断層情報をいち早く知ることによって津波予測精度の向上を図るために, 観測データを用いたリアルタイム津波予測手法を検討した. 津波シミュレーションによって求めた室戸沖および潮岬沖 (想定設置点) のGPS波浪計における津波水位の時系列変動から, ガウス・ザイデル法を用いて逆解析を実施し, 波源域と到達波高の推定を試みた. 大阪湾外の観測波形と逆解析によって求めた到達波高の時系列を比較したところ, 精度の良い結果が得られた. 波源域の推定および大阪湾内の津波高の予測には, 観測時間による影響が大きく, 観測時間が長くなれば, 津波波形の再現精度が上がることがわかった.

DOI： 10.2208/proce1989.53.311

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

2003年9月に韓国南部を縦断した台風14号によって慶南道馬山市では, 高潮による未曾有の災害が発生し, 地下施設への浸水により十数名の死者が出た. 本研究では, 地下施設内での海水の流動を3次元流体解析モデルで解析し, 地下室の浸水に要する時間, 流入する海水の流速等を明らかにし, 被災に至ったメカニズムを解明した. 次に, 今後の浸水対策として臨港部に高さ1mの防潮壁を建設する方法ならびに被害を受けた地下施設の入り口に高さ50cmの止水壁を設ける手法を提案し, その効果を数値計算で検討した. 計算の結果, 防潮壁や止水壁により地下施設への浸水開始時刻が遅くなり, 地下室内の浸水深も大幅に低下されることが明らかになった.

DOI： 10.2208/proce1989.52.206

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

A new observation system for wave overtopping at sea walls (On-site Wave Overtopping Sensor) has been developed. The system is composed of several step type wave gages installed at the edge of sea wall. The variation of water surface elevation above the crown level of sea wall is obtained during a storm employing the system. A field test using the system was carried out in the Port and Airport research Institute facing to the mouth of Tokyo bay when a typhoon passed in the bay. The measured data was applied to study on the time-dependent variation of wave overtopping rate at the observation point. The analyzed data demonstrated the applicability in field. The prototype system was installed in the Shimizu Port and it worked without any trouble for the target hours.

DOI： 10.1142/9789812701916-0350

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

実海域における海底地盤表層の動態については, 未だ不明な点が多い. 著者らは, 水深15mの観測サイトにおいて, 2003年と2004年に防波堤基礎地盤内における間隙水圧の応答観測を実施してきたが, 構造物下地盤において鉛直方向の観測深度の違いによって間隙水圧に位相差が生じるといったような原因の不明な特性を確認した. 本研究は, VOF-FEM法による間隙水圧の数値計算によって, 観測結果で得られた特性を明らかにし, 高波浪時の地盤内間隙水圧の波浪応答を解明するものである.

DOI： 10.2208/proce1989.52.851

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

本研究では, 防波堤直下の基礎地盤における水圧と間隙水圧の系統的な現地観測を実施し, そのデータに基づき, 高波浪が作用したときの海底砂質地盤の応答を明らかにすることを目的としている. 観測は, 2003年から2004年にかけて3つの台風 (T0310, T0416, T0423) を対象とし, 高知港の東第一防波堤サイトにおいて実施した. 現地観測の結果から, 残留間隙水圧の長周期変動成分は, 来襲波浪の波群特性と密接な関係があることがわかった. また, 液状化については, 構造物による上載圧の増加を考慮すると, 法先自由地盤を除いて, 発生する可能性は極めて低いという結論に達した.

DOI： 10.2208/proce1989.52.846

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

There is a little time to react until the tsunami arrival in each port in Osaka Bay in case of Nankai Earthquake occurrence. Therefore, it is possible to take precautions against the tsunami if appropriate tsunami information can be obtained. In this study, the real-time tsunami forecast system which can complement the forecast of the Meteorological Agency is examined. The real-time tsunami forecast method which is proposed in this research forecasts the tsunami that reaches in Osaka Bay 1 to 1.5 hours later by using the observed data outside the bay. The Shirahama Observation Tower in Tanabe Bay, Wakayama is considered as one of the offshore tsunami observation facilities. As a result of the examination, the accuracy of this method using the observed data was well and usefulness was confirmed.

DOI： 10.2208/prooe.21.145

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記述言語：日本語   出版者・発行元：土木学会  

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

台風0423号によって日本各地で起こった高波災害のうち, 和歌山県すさみ町周参見漁港西防波堤の被災を調査した. 沖波波浪の追算, 浅海波浪の推算計算による防波堤前面での波高分布, 防波堤の滑動量を解析した. Kim・Takayama (2004) の滑動量算定手法を用いて滑動量を求め, 実測値と比較してその有用性を検討した. ケーソンの傾き (tilting) によってケーソン後趾に生じる滑動抵抗力を考慮することにより, 周参見漁港で生じた防波堤の被災状況を再現し, 本解析手法の有用性を確認した.

DOI： 10.2208/proce1989.52.791

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

台風0314号によって葦山市の西側に位置する馬山市においては, 高潮による未曾有の災害が発生し, 地下施設への浸水により十数名の死者が出た.本研究では, 浸水被害の規模や地下への浸水状況を調べるために現地に赴き, 最高水位の痕跡値を調査し, 街路の地盤高や代表的な地下施設の寸法などを測量した.流入口が広い地下駐車場よりも下層に店舗が設定されるという, 建築構造上の欠陥が被害を大きくした一因であることが明らかになった.MARS法を用いた3次元流体解析モデルによって, 地下施設を含む浸水解析を実施した.解析結果を痕跡値の測量結果と比較したところ, 浸水状況をほぼ正確に再現することができた.

DOI： 10.2208/proce1989.51.1366

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

Knowledge on the flood risk due to tsunami and storm surge is slight in the persons living in coastal urban areas. The information of the size of anticipated damage and influence to evacuation routes is not enough for them to minimize the hazard risk by inundation.<BR>In this research, the inundation in the coastal urban area caused by tsunami attack is analytically estimated, and the display system on the website was developed. The site is capable for sending the understandable information on the risk through the internet.<BR>The inundation calculation was conducted according to the characteristics of the land use of coastal area, and the relational expression was derived between the distance from the seawalls line and the arrival time, the maximum depth, the maximum celerity. It is possible to display the inundation risk of the maximum design tsunami on the target coastal regions.

DOI： 10.2208/prooe.20.27

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

遊歩道付き護岸等の親水性施設での安全管理に役立てることを目的として, 護岸での越波や越流をリアルタイムで計測するためにオンサイト越波計が開発された.オンサイト越波計は, ステップ式波高計を改良して, 5cm間隔で電極を張り付けた長さ1mの測定桿を護岸上に設置したものである.オンサイト越波計の現地適用性を調べるために, 神奈川県久里浜湾の護岸で現地観測が実施された.2002年10月1日の台風0221号来襲時の観測において, 越流高から計算された10分間平均越波流量は, 同時に観測された集水升による越波流量に一致し, オンサイト越波計の現地適用性が検証された.

DOI： 10.2208/proce1989.50.626

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

都市臨海部は高度に開発されており地下施設が存在する場合もあるため, 構造物による影響を粗度として取り扱うだけでは不充分であり, 3次元的な浸水リスクの解析が必要と考えられる.本研究では, MARS法を応用した高精度な浸水リスク解析手法を提案し, 臨海都市部を対象にその有用性を検討した.解析の結果, 地上と地下の浸水状況を同時に再現できることを確認した.また, 浸水状況の解析結果をCGによって人の視点で可視化することもでき, 危険度の理解が容易になる.さらに, 地図データベースと土地利用状況情報を入手できれば, 各都市の臨海部において, 家のサイズまで認識可能な精度での浸水リスク予測が可能である.

DOI： 10.2208/proce1989.50.301

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

都市臨海部においては, 土地利用の高度化や地下空間の利用拡大といった高度利用が促進される反面, 伊勢湾台風を契機に整備されてきた海岸保全施設の老朽化, 異常潮位や温暖化による海面上昇など外力条件が厳しくなり, 大きなリスクが生じつつある. 沿岸津波についてはその危険度が広く認知されているのに対し, 津波による臨海部市街地の氾濫災害については, あまり想定されていない.本研究では, 建物と地下施設が混在した首都圏の複合市街地を対象に, 氾濫水の挙動特性や地下での浸水深, 流速などを測定し, 津波による浸水危険度の高さを模型実験で調べた.その結果, 地下空間の危険度は特に高く, 避難が非常に困難な状態になることがわかった.

DOI： 10.2208/proce1989.50.271