Efficiency improvement and validation of probabilistic tsunami inundation hazard assessment

2022 Fiscal Year Final Research Report

• Project/Area Number: 21K14391
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 25030:Disaster prevention engineering-related
• Research Institution: Kanto Gakuin University
• Principal Investigator: Fukutani Yo 関東学院大学, 理工学部, 准教授 (10785322)
• Project Period (FY): 2021-04-01 – 2023-03-31
• Keywords: 津波 / 確率論的津波ハザード評価 / 固有直交分解 / ガウス過程回帰 / 津波数値計算 / BPT分布 / 防潮堤 / 破堤確率

Outline of Final Research Achievements

We have proposed a method for efficiently and accurately analyzing computationally demanding probabilistic inundation evaluations by mode decomposing a large number of inundation depth distributions considering multiple uncertainties in the process from tsunami generation to inundation. We also incorporate statistical analysis to examine the outcomes. Our analysis not only considers conventional parameters related to earthquake faults, which have been traditionally used in probabilistic tsunami inundation assessment, but also factors in uncertainties that significantly influence the extent of inundated land, such as the probability of seawall rupture. The results obtained from our study include the spatial distribution of the probability of inundation depths reaching 1 meter or more within the next 50 years or 10 years in the specified area.

Free Research Field

海岸工学、津波工学

Academic Significance and Societal Importance of the Research Achievements

本研究では、各地域での津波浸水深の発生確率を効率的に評価する手法を提案した。固有直交分解を用いて、地震断層の不確定性に加えて、防潮堤の破堤確率も考慮した手法を構築したことは、学術的な意義が高い。提案手法を用いることで、沿岸部に防潮堤のある地域での陸域の津波浸水深の発生確率を、短期間で精度良く評価可能となるため、津波浸水確率を考慮した防災まちづくり計画や確率論的津波リスク評価等に利用されることが期待できる。