RAPID/Collaborative Research: Investigating Unanticipated Geotechnical Phenomena in Kumamoto, Japan, Observed from the April 2016 Earthquake Sequence

快速/协作研究：调查从 2016 年 4 月地震序列中观察到的日本熊本意外岩土现象

• 批准号: 1727594
• 负责人: Kevin Franke
• 金额: $ 15.65万
• 依托单位: Brigham Young University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-04-01 至 2018-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1727594&HistoricalAwards=false
• 关键词: RAPID; Collaborative; Research; Investigating; Unanticipated

This collaborative U.S.-Japan Grant for Rapid Response Research (RAPID) award will investigate unanticipated and poorly understood geotechnical phenomena observed following the April 2016 Kumamoto earthquake sequence (KES) in Japan. The Geotechnical Extreme Events Reconnaissance (GEER) organization mobilized a U.S. reconnaissance team to explore the affected area immediately following the KES. The U.S. team in collaboration with Japanese investigators identified significant case histories that warrant further investigation due to their unique, unanticipated, and poorly understood nature, as well as their important potential implications for seismic design and safety in the U.S. and around the world. These case histories include, among other things: an unexplained 10km-long depression zone within the Mount Aso volcano caldera that caused significant damage to structures and transmission lines; a fault rupture through the spillway of a large dam impounding a full reservoir; and surprisingly limited observations of soil liquefaction and its effects for an earthquake of this size and apparent site conditions. This RAPID award supports a detailed study of the underlying causes behind these observations through: (1) the use of state-of-the-art remote sensing techniques to collect perishable surface topology, soil deformation, and structure settlement or tilt information from known liquefaction and major landslide sites; (2) the collection of preliminary geotechnical, seismic, geologic, and topographic information from potential case history sites of interest; and (3) the performance of a comprehensive set of laboratory tests on retrieved samples followed by preliminary simulations to evaluate the soil's resistance to liquefaction and response under cyclic loading. In doing so, this award contributes to the state of knowledge and practice in critical areas of geotechnical earthquake engineering and hence, the resilience of geotechnical structures and infrastructure globally. Collaboration with Japanese researchers through this study will improve the relationship and cooperation between the two countries, and will provide valuable international research experience for the PIs and the graduate students involved in this project. This grant will advance the science and practice of geotechnical earthquake engineering by enhancing the fundamental understanding of seismic-induced ground deformations and liquefaction triggering. This RAPID project will enable the collection of valuable and perishable information related to landslides, liquefaction triggering and effects, and earthquake-induced ground deformations from the 2016 KES in Japan. There are a number of phenomena observed after the KES that cannot be explained by the existing state of knowledge or current analytical and/or empirical prediction models. These phenomena could have important implications for seismic design in locations with similar geology and geomorphology in the U.S. Information collected from the affected sites followed by laboratory testing and analysis will increase our understanding of the underlying causes of the geotechnical phenomena observed following the KES, which will ultimately impact the state of geotechnical earthquake engineering practice. The engineering community will benefit from learning why soil liquefaction did not occur to the extent that it was predicted in this region. Joint application of 3D digital surface modeling using UAV-based aerial photography and terrestrial LiDAR techniques will advance the science and art of remote sensing in geotechnical engineering and will improve the way surficial evidence of geotechnical earthquake phenomena is collected. Further, preliminary field and laboratory data collected from this RAPID will guide and inspire a larger international collaborative research effort to more thoroughly investigate the observed unique geotechnical phenomena and damage from this series of earthquakes.

这项合作的美国快速响应研究授予（Rapid）奖项将调查日本2016年4月Kumamoto地震序列（KES）之后观察到的意外且知之甚少的岩土现象。岩土技术极端事件侦察组织（GEER）组织动员了一个美国侦察小组，在KES之后立即探索受影响的地区。美国团队与日本调查人员合作确定了重要的案例历史，由于其独特，意外且知识不足的性质以及其对美国和世界各地的地震设计和安全性的重要影响，因此需要进一步调查。这些案例历史包括：在ASO火山火山口山内无法解释的10公里长的凹陷区，对结构和传输线造成了重大破坏；大坝的溢洪道破裂的断层破裂，蓄水库；令人惊讶的是，对土壤液化的观察及其对这种大小和明显地点条件的地震的影响。这项快速奖项支持了对这些观察结果背后的根本原因的详细研究：（1）使用最先进的遥感技术来收集可腐烂的表面拓扑，土壤变形，结构和结构沉降或从已知的液化和主要滑坡地点的倾斜信息； （2）从潜在的病史现场收集了初步的岩土，地震，地质和地形信息； （3）对检索样品进行了全面的实验室测试的性能，然后进行初步模拟，以评估土壤在循环载荷下对液化和反应的抗性。在这样做的过程中，该奖项有助于岩土技术地震工程的关键领域的知识和实践状态，因此，全球岩土结构和基础设施的弹性。通过这项研究与日本研究人员的合作将改善两国之间的关系和合作，并将为PIS和参与该项目的研究生提供宝贵的国际研究经验。这笔赠款将通过增强对地震诱导的地面变形和液化触发的基本理解来提高岩土技术工程的科学和实践。这个快速的项目将使与滑坡，液化触发和效果有关的有价值和易腐的信息以及地震引起的地震诱导的地面变形。在KES之后观察到了许多现象，这些现象无法用现有的知识状态或当前的分析和/或经验预测模型来解释。这些现象可能对从受影响的地点收集的地质和地质学相似的地点的地震设计具有重要意义，然后进行实验室测试和分析，将增加我们对岩土技术现象的基本原因的理解，最终会影响地球地球地震工具练习的状态。工程界将受益于了解为什么没有在该地区预测的土壤液化的范围内。使用基于无人机的航空摄影和陆地激光雷达技术的3D数字表面建模的联合应用将推动岩土工程中遥感的科学和艺术，并将改善收集岩土技术地震现象的表面表面证据的方式。此外，从这种快速收集的初步领域和实验室数据将指导和激发更大的国际协作研究工作，以更彻底地研究观察到的独特的岩土现象和这一系列地震的损害。