CAREER: Determination of Performance-Based Earthquake Engineering Parameters using Paleoseismic Techniques

该项目的目标是开发和验证一个框架，用于评估中到大地震是高后果，低概率事件的地区的地震危险性参数，以便能够正确实施基于性能的地震工程（PBEE）。PBEE的实施需要结构系统的脆弱性和概率量化的地震危险是已知的，以建立由于地震事件的具体损失的年度概率。然而，在中到大地震的重现期明显长于历史地震记录的地区，如太平洋西北部（PNW）和美国中部/东部（CEUS），地震危险性的概率量化是高度不确定的-我们知道中到大地震发生在这些地区，我们只是不知道事件有多大或它们发生的频率。古地震技术，特别是古液化调查（即，研究仪器前地震的液化特征），是将地震记录延伸到史前时期的最合理的方法。这些技术允许建立中大型地震的复发时间和特征，从而消除了在这些地区实施PBEE的主要障碍。该项目的影响将是大大降低新设计和建造的标准和危险设施的地震风险。该项目是特别及时的，因为国家（以及世界）重新对核电厂的建设感兴趣，如果要安全地实现，需要适当量化地震危险。对于新工厂可能位于的美国地区（例如，可靠的古地震资料对地震危险性评估是绝对必要的。除了来自密歇根大学（UM）的研究生外，来自UM和瓦尔帕莱索大学的本科生将参加一个示范演习，在演习中将对瓦巴什山谷地震带进行古地震调查。此外，作为该项目的一部分，PI正在为退伍军人启动一个外联方案。建立这种外联的原因是，退伍军人往往拥有许多生活技能，使他们能够在学术上取得成功。绝大多数入伍的退伍军人来自美国较低的社会经济阶层，与一般人口相比，很大一部分退伍军人是代表性不足的少数民族。

The objective of this project is to develop and validate a framework for assessing seismic hazard parameters for regions where moderate-to-large earthquakes are high-consequence, low-probability events so that performance-based earthquake engineering (PBEE) can be properly implemented. The implementation of PBEE requires both the fragility of structural systems and the probabilistically quantified seismic hazard to be known in order to establish the annual probability of specific losses due to seismic events. However, the probabilistic quantification of the seismic hazard is highly uncertain in regions where the return period of moderate-to-large earthquakes is significantly longer than the historic earthquake record, such as in the Pacific Northwest (PNW) and the central/eastern United States (CEUS) -- we know moderate-to-large earthquakes occurred in these regions, we just do not know how large the events were or how often they occur. Paleoseismic techniques, particularly paleoliquefaction investigations (i.e., the study of liquefaction features from pre-instrumental earthquakes), are the most plausible way to extend the earthquake record into prehistoric times. Such techniques allow both the recurrence time and characteristics of moderate-to-large earthquakes to be established and, thus, remove a major impediment to implementing PBEE in these regions. The impact of the project will be the significant reduction of the seismic risk of newly designed and constructed standard and hazardous facilities. The project is particularly timely as the nation (as well as the world) renews their interest in the construction of nuclear power plants, which if to be realized safely requires proper quantification of seismic hazard. For regions of the US where the new plants are likely to be located (e.g., CEUS), reliable paleoseismic data are absolutely essential for assessing seismic hazard. In addition to graduate students from the University of Michigan (UM), undergraduate students from both UM and Valparaiso University will participate in a demonstration exercise in which a paleoseismic investigation of the Wabash Valley Seismic Zone will be performed. Also, as part of this project, the PI is initiating an outreach program for military veterans. The reason for establishing this outreach is that veterans tend to possess many of life's skills that will enable them to succeed in academics. The vast majority of enlisted veterans come from the lower socio-economic echelons in the US, and a large percentage of veterans are underrepresented minorities, as compared to the general population.