Numerical modelling of coastal inundation from Cascadia Subduction Zone tsunamis and implications for coastal communities on western Vancouver Island, Canada
Numerical modelling of coastal inundation from Cascadia Subduction Zone tsunamis and implications for coastal communities on western Vancouver Island, Canada
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卡斯卡迪亚俯冲带海啸造成的沿海洪水的数值模拟及其对加拿大温哥华岛西部沿海社区的影响
DOI：
10.1007/s11069-019-03614-3
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发表时间：
2019
期刊：
影响因子：
3.7
通讯作者：
T. Shibayama
中科院分区：
文献类型：
--
作者：
T. Takabatake;Philippe St;I. Nistor;Jacob Stolle;T. Shibayama
在本研究中，进行了数值模拟，以估计的时空特征的海啸淹没城市的温哥华岛，加拿大，作为一个结果，各种潜在的卡斯卡迪亚俯冲带地震的确定性方案。通过改变地震震级和相关的滑动距离，这些参数对海啸波的传播，淹没，以及对基础设施和建筑物的可能损害的影响进行了研究。一个数值海啸淹没模型的基础上，非线性浅水方程组的构造，利用可利用的水深和地形数据，并应用到三个研究领域：城市的港口阿尔贝尔尼，区的Ucluelet，区的Tofino。数值结果表明，海啸最大淹没深度和淹没空间范围对地震震级敏感，而海啸到达时间对地震震级不敏感。对于最坏情况下的地震情景调查（MW9.3），所有三个研究领域广泛淹没。详细分析了海啸波振幅和陆地淹没深度、流速、水动力和深度-速度积的结果，以评估海啸对内陆建筑物的影响。潜在的损害估计与以前提出的脆弱性曲线的木材，钢筋混凝土，钢框架建筑物。结合作者为更好地了解这些地区的一般特征而进行的现场勘察访问，模型结果表明，建筑物，特别是木制建筑物将受到重大损害，有相当大的生命损失风险。
In the present study, numerical simulations were conducted to estimate the spatio-temporal characteristics of tsunami inundation for municipalities on Vancouver Island, Canada, as a result of various potential Cascadia Subduction Zone earthquake deterministic scenarios. By varying the earthquake magnitude and associated slip distance, the influence of these parameters on the tsunami wave propagation, inundation, and the possible damage on infrastructure and buildings was investigated. A numerical tsunami inundation model based on nonlinear shallow water equations was constructed using publically available bathymetric and topographic data and applied to three study areas: the City of Port Alberni, the District of Ucluelet, and the District of Tofino. The numerical results obtained in this study show that the maximum tsunami inundation depth and spatial extent of inundation are sensitive to the earthquake magnitude, whereas the tsunami arrival time is not. For the worst-case earthquake scenario investigated (MW9.3), all of the three study areas were extensively inundated. Results of tsunami wave amplitude and overland inundation depth, flow velocity, hydrodynamic force, and depth–velocity product are analysed in detail to assess the impacts of the tsunami on inland buildings. The potential damage was estimated with previously proposed fragility curves for wood, reinforced concrete, and steel frame buildings. In conjunction with a site reconnaissance visit by the authors for better understanding the general characteristics of these areas, model results suggest that significant damage to buildings would occur, especially to wooden constructions, with considerable risk of loss of human life.