RAPID/Collaborative Research: Advanced Site Characterization of Key Ground Motion and Ground Failure Case Histories Resulting from the Mw7.8 Kaikoura, New Zealand, Earthquake

RAPID/协作研究：新西兰凯库拉 Mw7.8 地震造成的关键地震动和地面故障案例历史的高级现场表征

基本信息

批准号：
1724575
负责人：
Russell Green
金额：
$ 3.7万
依托单位：
Virginia Polytechnic Institute and State 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：
2017-02-01 至 2019-01-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1724575&HistoricalAwards=false
关键词：
RAPID Collaborative Research Advanced Site

项目摘要

A large and widely-damaging earthquake has not occurred in the U.S. for over 20 years. However, advancements have continued to be made in earthquake engineering by observing the effects of large earthquakes in countries that have similar seismic design standards and well-constructed infrastructure. Documenting the effects of earthquakes in a country like New Zealand, which has rigorous building codes and similar infrastructure to the U.S., provides the greatest opportunities for learning lessons that will be directly transferable to our country. The Mw7.8 Kaikoura earthquake provides a unique opportunity to evaluate in considerable depth the effects of earthquake shaking on diverse types of infrastructure, in cities of different population densities, underlain by various types of soil profiles, subjected to a wide range of shaking intensities. These circumstances provide an invaluable opportunity to study ground shaking amplification caused by site, basin and topographic effects, and cases of liquefaction-induced ground failure, that will be directly applicable to U.S. cities such as Los Angeles, San Francisco, Seattle and Salt Lake City. Urgency is required because the PIs currently have access to some key facilities, such as the CentrePort of Wellington. After they have rebuilt the port, for example, there will no longer be access and the opportunity to characterize the ground as it was immediately after the earthquake will be lost . Moreover, New Zealand researchers are rapidly mobilizing to carry out initial studies at key sites. In order to combine resources and expertise, the project will need to also mobilize quickly. The end-goal of this project is to benefit society at-large through increased resiliency, sustainability and affordability of civil infrastructure via improved seismic design. This work will also serve to strengthen international research collaborations between the U.S. and New Zealand, and will provide U.S. graduate students with rewarding international travel experiences that will serve to balance their technical education and expose them to the globally-connected problems that still exist in earthquake engineering. In short, the broader impacts of this work stretch far beyond the borders of New Zealand and will positively impact seismic hazard practices in the U.S. and abroad.The intellectual merits of the research plan include an improved understanding of: (1) ground motion stratigraphy, basin and topographic effects in complex geotechnical settings; (2) liquefaction response of gravelly soils; (3) the influence of non-liquefiable capping layers on liquefaction damage potential; and (4) the response of buildings and critical port infrastructure on liquefiable soil. Of particular interest are the much-higher-than-expected long period ground motions recorded on natural and reclaimed soil sites 60 km from the fault rupture in the capital city of Wellington. It is hypothesized that highly variable topography, both above and below the valley floor, resulted in complex interactions between stratigraphy, basin and topographic effects, amplifying ground motions. Advanced site characterization is needed in the form of deep shear wave velocity (Vs) profiling and topographic array studies to investigate these phenomena. Without this information, it will be impossible to place observations of structural damage and ground failure caused by the Kaikoura earthquake in context. Wellington is the perfect test bed for this study, because abruptly changing topography allows all of these ground motion effects to be studied on a remarkably small scale of several kilometers. Advanced site characterization is also needed at Wellington's port facility, where surprisingly severe liquefaction damage occurred under moderate shaking (PGA values of 0.13 - 0.24g) from this relatively distant earthquake In addition to documenting the damage to wharves and shipping cranes due to liquefaction-induced lateral spread movements, there are rare incidents of gravel liquefaction to document at CentrePort Other important ground failure sites on the South Island should also be characterized rapidly to add valuable, perishable data to the U.S. soil liquefaction triggering and lateral spreading empirical databases. Advanced site characterization studies are planned at key case history sites in Wellington and the South Island using a combination of: (1) Single-station horizontal-to-vertical spectral ratio noise measurements for investigating fundamental site periods, (2) Combined active-source and ambient-wavefield surface wave testing for developing deep Vs profiles; (3) Cone penetration tests for revealing detailed site stratigraphy; and (4) Direct-push crosshole tests for high-resolution Vs and Vp profiles. Collecting and analyzing these data will help to better understand valuable lessons-learned that are directly transferrable to improved seismic design practices in the U.S.

在20多年来，美国没有发生大型且受到广泛破坏的地震。但是，通过观察具有类似地震设计标准和良好结构良好基础设施的国家的大地震的影响，在地震工程中的进步继续取得进步。记录了像新西兰这样一个国家的地震的影响，该国家具有严格的建筑法规和类似的基础设施，为学习提供了最大的学习机会，可以直接转移到我们的国家。 MW7.8 Kaikoura地震提供了一个独特的机会，可以在不同种群密度的城市中摇晃地震摇动对各种类型的基础设施的影响，以各种类型的土壤剖面为基础，受到各种类型的土壤特征的支持，并受到了广泛的摇动强度。这些情况提供了一个宝贵的机会，可以研究由现场，盆地和地形效应以及液化引起的地面故障引起的地面震动放大的机会，这些障碍将直接适用于洛杉矶，旧金山，西雅图，西雅图和盐湖城等美国城市。需要紧急情况，因为PIS目前可以访问某些关键设施，例如惠灵顿的中央区。例如，在他们重建港口之后，将不再有访问权限，并且有机会将地面进行表征，因为地震会丢失之后。此外，新西兰研究人员正在迅速动员在关键站点进行初步研究。为了结合资源和专业知识，该项目还需要快速动员。该项目的最终目标是通过改进的地震设计通过提高弹性，可持续性和可负担性的能力来使社会上的社会受益。这项工作还将有助于加强美国和新西兰之间的国际研究合作，并将为美国研究生提供有意义的国际旅行经验，以平衡其技术教育并使他们面临地震工程中仍然存在的全球联系问题。简而言之，这项工作的更广泛影响远远超出了新西兰的边界，将对美国和国外的地震危害实践产生积极影响。研究计划的智力优点包括对：（1）地面运动地层，盆地和地形在复杂的岩土技术环境中的地面运动地层，盆地和地形效应；（2）砾石土壤的液化反应；（3）不可利用的上限层对液化损伤潜力的影响；（4）建筑物和关键的港口基础设施对液化土壤的响应。特别令人感兴趣的是距首都惠灵顿断层破裂60公里的自然和再生土壤地点上的长期地面动作高。假设高度可变的地形在山谷地板上方和下方，导致地层，盆地和地形效应之间的复杂相互作用，从而扩大了地面运动。需要先进的位点表征，以深层剪切波速度（VS）分析和地形阵列研究的形式进行研究。没有这些信息，就无法在上下文中观察到由Kaikoura地震造成的结构损害和地面故障。惠灵顿是这项研究的理想测试床，因为突然变化的地形允许所有这些地面运动效应都可以在几公里的小规模上进行研究。惠灵顿港口设施还需要进行先进的现场表征，在此相对较远的地震中，在中等震动（PGA值为0.13-0.24g）下发生了令人惊讶的严重液化损害，此外，除了记录了对鲸鱼的损害和运输的造成的危险造成的危险造成的危险造成的千里联元素，还可以在液体上造成的其他杂物，这是较罕见的杂物，这也是千里联运的杂物。迅速的特征是在美国土壤液化触发和横向扩散的经验数据库中添加有价值的易腐数据。先进的现场表征研究是在惠灵顿和南岛的关键病史现场使用：（1）以下组合：（1）单站水平与垂直频谱比率测量噪声测量值，用于研究基本场地周期，（2）组合活性源和环境 - 环境和环境波域的表面波测试，用于开发深度VS vs vs vs vs vs vs vs vs vs vs vs；（3）用于揭示详细位点地层学的锥体穿透测试；（4）高分辨率与VP配置文件的直接孔孔测试。收集和分析这些数据将有助于更好地理解有价值的课程，这些课程可直接转移到美国改进的地震设计实践中