NEESR: Interaction of Tsunamis with Short Waves and Bottom Sediment - Numerical and Physical Modeling

结合沉积物输运过程，研究了短海浪与长瞬态海啸的相互作用。这符合研究与自然海洋学过程相协调的海啸产生过程的主题，并将从两个角度进行：海啸对搬运和重新加工的沉积物床的影响；以及泥沙负荷对海啸输送力的影响。数值模拟将成为这项工作的支柱，物理建模为过程研究、参数化和验证提供数据。一个基于光滑粒子流体动力学的复杂模型将被紧密地整合到实验计划中。实验计划在前两年为俄勒冈州立大学的乔治·e·布朗地震工程模拟网络（NEES）大波水槽设施进行。第一组实验将侧重于评估海啸的传输能力，以便为传输模型开发拾取功能和其他参数化。第二组实验将研究全床演化。在所有的实验中，强迫将包括海啸和海啸-膨胀的组合条件。测量将包括：自由地表高程；近底速度（来自声波多普勒测速仪）；沉积物浓度（来自光学和声学后向散射装置的垂直堆叠）；和垂直速度剖面（通过一对向上/向下看脉冲相干声学多普勒剖面仪）。这些测量还将以几种不同的方式用于评估海啸的消散。为了测量海啸下沉积物的改造和再分配程度，沉积物样本将使用数字光学粒度分析仪进行分析。该项目的数据将存档，并通过NEES项目仓库/数据存储库（http://www.nees.org）向公众提供。拟议工作的更广泛影响涉及目前关于海啸破坏性性质的知识状况以及在实验室研究中如何有效地反映海啸的破坏性。预计这项工作的结果将影响到有关可能遭受海啸的沿海地区基础设施卫生、应急程序和公共安全的现行政策。还概述了与NEES大浪水槽设施的教育和外展人员合作的计划，以帮助他们制定有关海啸及相关危害的公众参与和教育的既定计划，以及他们鼓励科学和工程职业的计划。这将包括在大浪水槽设施中进行海啸与沉积物相互作用的现场演示，在此期间，公众将能够目睹汹涌的海啸的力量。该奖项是国家减少地震灾害计划（NEHRP）的一部分。

The interaction between short ocean waves and long transient tsunamis is studied in conjunction with sediment transport process. This is in keeping with the theme of the study of tsunami-generated processes in concert with natural oceanographic processes, and will be done from two viewpoints: that of the tsunami's effect on the transported and reworked sediment bed; and that of the effect of the sediment load on the transporting power of the tsunami. Numerical modeling will form the backbone of this work, with physical modeling providing data for process study, parameterization and validation. A sophisticated model based on smoothed particle hydrodynamics will be tightly integrated into the experimental plan. Experiments are planned for the George E. Brown, Jr. Network for Earthquake Engineering Simulation (NEES) Large Wave Flume Facility at Oregon State University during the first two years. The first set of experiments will focus on evaluating the transport power of the tsunami in order to develop the pickup function and other parameterizations for the transport model. The second set of experiments will investigate full bed evolution. In all experiments, forcing will consist of tsunamis and combined tsunami-swell conditions. Measurements will be comprised of: free surface elevations; near-bottom velocities (from acoustic Doppler velocimeters); sediment concentration (from vertical stacks of optical and acoustic backscatter devices); and vertical velocity profiles (via pairs of upward/downward looking pulse-coherent acoustic Doppler profilers). These measurements will also be used to evaluate the dissipation of the tsunami in several different ways. To gage the degree of sediment reworking and redistribution under a tsunami, sediment samples will be analyzed using a digital-optical grain size analyzer. Data from this project will be archived and made available to the public through the NEES Project Warehouse/data repository (http://www.nees.org). The broader impacts of the proposed work address the present state of knowledge concerning the destructive nature of the tsunami and how effectively it is represented in laboratory studies. It is anticipated that the results of this work will affect present policies governing infrastructural health, emergency procedures and public safety in coastal areas potentially subject to tsunamis. A plan is also outlined concerning work with the NEES Large Wave Flume Facility's education and outreach personnel in aiding their established plans concerning public engagement and education regarding tsunamis and associated hazards, as well as their plans for encouraging careers in science and engineering. This will include live demonstrations of tsunami-sediment interaction in the Large Wave Flume Facility, during which the public will be able to witness the power of an onrushing tsunami. This award is part of the National Earthquake Hazards Reduction Program (NEHRP).