Full-Waveform Inversion of Seismic Input Motions in a Truncated Domain

截断域中地震输入运动的全波形反演

基本信息

批准号：
2044887
负责人：
Chanseok Jeong
金额：
$ 4.88万
依托单位：
Central Michigan University
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2020
资助国家：
美国
起止时间：
2020-09-01 至 2022-03-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=2044887&HistoricalAwards=false
关键词：
Full Waveform Inversion Seismic Input

项目摘要

Under this award a new full-waveform inversion method will be developed for the identification of the seismic input motion on the truncation surface of a computational domain, using existing sparse seismic records. This new method will allow engineers to reconstruct the spatial and temporal distribution of the seismic input motion, without the need to resort to the reconstruction of the seismic event at the hypocenter, as is typically the case. Then, by using the reconstructed seismic motion, it will be possible to study the effect of an earthquake on the built environment, including subsurface systems (soil, foundations, and underground structures). Therefore, the method will serve as a tool to assess holistically the impact of earthquakes on the built environment during seismic events. The proposed research will present the mathematical and computational modeling of the new seismic-input identification method, as well as numerical results showing the accuracy, scalability, and efficiency of the method. The computer code, input data, and tutorials, necessary for using the new seismic-input identification method, will be disseminated through the DesignSafe Cyberinfrastructure. These materials will help informed users to easily follow the research and extend it. Participating graduate students will gain broad knowledge and experience on wave propagation analyses and inverse problems. Moreover, hands-on projects will be used to motivate high school students, from underrepresented groups, to pursue STEM careers during the planned outreach program ``How do waves work?: watch, feel, and analyze waves??.To date, there has been no robust numerical method that can identify complex, incoherent seismic input motions in a solid, truncated by a wave-absorbing boundary. Existing methods are limited to either simplified deconvolution techniques or large-scale seismic-source inversion approaches that can identify the seismic source parameters (however simple or complicated the adopted seismic source model may be) at the hypocenter. However, there are many complexities, inaccuracies, and uncertainties associated with the large-scale inversion approach that render it impractical for near-surface simulations. It is the aim of this research to bypass the complexities associated with the large-scale seismic source inversion by targeting the seismic-motion reconstruction near the surface. Specifically, this research will focus on the reconstruction of effective seismic input motion at the Domain Reduction Method (DRM) boundary, using a partial differential equation-constrained optimization method. The semi-infinite extent of the computational domain will be truncated by using Perfectly-Matched-Layers, and state and adjoint wave equations will be solved using the finite element method. The new seismic-input identification method will be the most accurate and efficient method for inferring seismic input motions in soil-structure systems. This method can accommodate arbitrary soil heterogeneity.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

在此奖项下，将使用现有的稀疏地震记录来开发一种新的全波反转方法，以识别计算域截断表面上的地震输入运动。这种新方法将使工程师能够重建地震输入运动的空间和时间分布，而无需像通常情况下在低温下重建地震事件的重建。然后，通过使用重建的地震运动，可以研究地震对建筑环境的影响，包括地下系统（土壤，基础和地下结构）。因此，该方法将作为在地震事件中整体评估地震对建筑环境的影响的工具。拟议的研究将介绍新的地震输入识别方法的数学和计算建模，以及显示该方法的准确性，可扩展性和效率的数值结果。使用新的地震输入标识方法所需的计算机代码，输入数据和教程将通过DesignSafe Cyberinfrastructure传播。这些材料将帮助用户轻松地进行研究并扩展研究。参与的研究生将在波浪传播分析和反问题上获得广泛的知识和经验。 Moreover, hands-on projects will be used to motivate high school students, from underrepresented groups, to pursue STEM careers during the planned outreach program ``How do waves work?: watch, feel, and analyze waves??.To date, there has been no robust numerical method that can identify complex, incoherent seismic input motions in a solid, truncated by a wave-absorbing boundary.现有方法仅限于简化的反卷积技术或大规模地震源代码反演方法，这些方法可以识别高分子的地震源参数（无论多么简单或复杂的地震源模型）。但是，与大规模倒置方法相关的复杂性，不准确性和不确定性使其对于近距离模拟而变得不切实际。这项研究的目的是绕过与大规模地震源倒置相关的复杂性，通过靶向地下震动运动重建。具体而言，这项研究将使用部分微分方程约束的优化方法重建有效的地震输入运动（DRM）边界的有效地震输入运动。计算域的半无限程度将通过使用完美匹配的层截断，并且将使用有限元方法求解状态和伴随波程。新的地震输入识别方法将是推断土壤结构系统中的地震输入运动的最准确和有效的方法。该方法可以适应任意的土壤异质性。该奖项反映了NSF的法定任务，并且使用基金会的知识分子优点和更广泛的影响标准，被认为值得通过评估来支持。