RAPID/Collaborative Research: Subsurface Characterization of Liquefaction Case Histories from the 2023 Kahramanmaras Earthquake Sequence

该快速反应研究（Rapid）奖将提供有关地震期间建筑物和地面性能的详细记录案例。美国已经有近30年没有经历过破坏性大的地震了。然而，通过了解具有类似地震风险和基础设施的国家（如土耳其）的地震破坏情况，可以取得进展。2023年土耳其Kahramanmaras地震序列提供了一个独特的机会来评估地震对不同地质环境下不同基础设施的影响，这些环境受到各种地震强度的影响。震后观测可以研究近断层地面运动的影响、液化引起的基础设施破坏以及粉土和粘土的循环行为。对关键地点的地面特征进行描述可以开发直接适用于旧金山、西雅图和孟菲斯等美国城市的见解。这项工作将与土耳其研究人员合作进行，尽可能多地从这些地震中学习。该项目的目标是在考虑到地震影响的情况下，通过提高民用基础设施的弹性、可持续性和可负担性来造福社会。该奖项将通过支持一名高级研究员与来自美国四家机构的三名早期职业研究人员的互动，以及一名研究生的指导，帮助培养下一代美国地震工程领导者。该项目的重点是获取关键地点的地下数据，这对于开发地震期间建筑和地面性能的良好记录的历史案例至关重要。地下信息将主要通过地震压锥穿透试验收集，以表征地面条件，包括剪切波速，并探测关键土层。此外，将进行探索性土壤钻孔，以获取土壤指数测试的样本。本项目收集的地下数据将提供关键信息，以显著扩大液化-基础设施相互作用的综合历史案例的数量，重点关注(1)近断层地区受地面震动和地面破坏影响的基础设施，(2)液化引起的建筑破坏，以及(3)粉土和粘土的液化。这三个主题代表了由于缺乏案例历史而存在知识空白的地震工程领域。此外，地下数据将有助于评估Iskenderun频繁发生的沿海洪水（可能是由于液化引起的地面运动），从而提供有关气候变化和地震多重灾害的见解。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This Grants for Rapid Response Research (RAPID) award will provide well-documented case histories on building and ground performance during earthquakes. The US has not experienced a large, widely-damaging earthquake for nearly 30 years. However, advancements can be made by understanding earthquake damage in countries with similar seismic risks and infrastructure, such as Turkey. The 2023 Kahramanmaras, Turkey earthquake sequence provides a unique opportunity to evaluate the effects of earthquake shaking on diverse infrastructure in varied geologic environments subjected to a wide range of shaking intensities. The post-earthquake observations enable the study of the effects of near-fault ground motions, liquefaction-induced infrastructure damage, and the cyclic behavior of silt and clay soils. Characterization of the ground at key sites allows to develop insights that are directly applicable to US cities such as San Francisco, Seattle, and Memphis. The work will proceed collaboratively with Turkish researchers to learn as much as possible from these earthquakes. The goal of the project is to benefit society through increased resiliency, sustainability, and affordability of civil infrastructure considering seismic impacts. The award will help train the next generation of US earthquake engineering leaders by supporting the interaction of a senior researcher with three early-career researchers from four institutions across the US, as well as the mentorship of a graduate student. This project focuses on obtaining subsurface data at key sites, which is essential to developing well-documented case histories of building and ground performance during earthquakes. The subsurface information will be collected primarily through seismic piezocone penetration tests to characterize the ground conditions, including shear wave velocity, and to detect critical soil layers. Additionally, exploratory soil borings will be performed to obtain samples for soil index testing. The subsurface data collected in this project will provide critical information to significantly expand the number of comprehensive case histories of liquefaction-infrastructure interactions, focusing on (1) infrastructure affected by ground shaking and ground failure in the near-fault region, (2) liquefaction-induced building damage, and (3) liquefaction of silts and clays. These three topics represent areas of earthquake engineering with knowledge gaps due to a dearth of case histories. Additionally, the subsurface data will provide insights regarding climate change and earthquake multi-hazards by contributing to evaluations of the frequent coastal flooding of Iskenderun, presumably due to liquefaction-induced ground movements.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.