CAREER: Multiscale Probabilistic Characterization of Seismic Site Response in Highly Uncertain Environments

该学院早期职业发展（Career）奖将在多个尺度上推进土壤对地震地面震动反应的科学知识，并将其纳入供水系统的系统级概率地震危害评估。地表附近空间变化的地质构造对地震动强度有显著影响（称为场地效应），并可能加剧对建筑环境的破坏。饮用水和污水处理设施是至关重要的生命线，因为地震破坏对灭火能力、公共卫生和经济产生了重大的负面影响。这项CAREER拨款将促进供水系统系统级地震危害评估的范式转变，以克服目前过度简化近地表地质条件影响的做法。考虑场地影响和不确定性可以减少损害和服务损失，并改进事后快速损害评估。教育方面的影响包括重塑学生在数据分析和不确定性量化方面的培训，而主要的外联影响是在拉丁美洲启动了第一个地震工程和地震学社区联盟（E2SCALA）。该职业基金的目标是：(1)推进现场反应多尺度评估的基础科学知识，并将其纳入配水系统的系统级概率地震危害分析；(2)改进保留策略，扩大妇女和拉丁美洲学生在STEM领域的参与。数值模拟，地理空间分析和不确定性量化将被使用。将制定一个新的条件场地响应模型，该模型能够适应并整合所有可用的地下数据和相关的不确定性。空间可变的场地效应对地震动强度测量之间的空间相关性的影响将被量化，以及场地响应的方位角依赖性。将创建一种改进的系统级概率方法，该方法仅在系统的关键位置合并局部站点效应，并且为了计算效率，将在其他地方假设遍历性。改进的概率方法将在供水系统的三个案例研究中实施。“Escala”在西班牙语中的意思是“攀登”和“扩展”，这是这个CAREER项目的关键驱动因素。E2SCALA将为合作学术机构的拉丁美洲学生提供开放的教育资源（英语和西班牙语）、多层虚拟指导和合作机会；帮助学生发挥他们最大的潜力（攀登），同时建立一个与他们的社区目标一起成长的网络（扩大规模）。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 Faculty Early Career Development (CAREER) award will advance scientific knowledge on the response of soils to earthquake ground shaking at multiple scales and enable its incorporation into system-level probabilistic seismic hazard assessments for water distribution systems. The spatially variable geologic structure near the ground surface exerts a significant influence on the intensity of ground shaking (known as site effects) and can exacerbate damage to the built environment. Drinking water and wastewater utilities are critical lifelines because of the significant negative effects of earthquake damage on the ability to fight fires, on public health, and the economy. This CAREER grant will foster a paradigm shift in system-level seismic hazard assessments for water distribution systems to overcome current practices that oversimplify the effects of near-surface geologic conditions. Accounting for site effects and uncertainty can reduce damage and service losses and improve post-event rapid damage assessments. The educational impacts include reshaping students’ training in data analytics and uncertainty quantification, while the main outreach impact is the launch of the first Earthquake Engineering and Seismology Community Alliance in Latin America (E2SCALA).The goals of this CAREER grant are to (1) advance scientific knowledge underlying multiscale assessments of site response and incorporate it into system-level probabilistic seismic hazard analysis for water distribution systems, and (2) improve retention strategies for and broaden participation of women and Latin American students in STEM fields. Numerical modeling, geospatial analytics and uncertainty quantification will be used. A new conditional site response model capable of adapting to and integrating all available subsurface data and the associated uncertainties will be formulated. The influence of spatially variable site effects on spatial correlations among ground motion intensity measures will be quantified, as well as azimuth-dependencies in site response. An improved system-level probabilistic approach that incorporates local site effects only at critical locations of the system will be created, and ergodicity will be assumed elsewhere for computational efficiency. The improved probabilistic approach will be implemented in three case studies of water distribution systems. "Escala" means "to climb" and also "to scale" in Spanish and those are key drivers of this CAREER project. E2SCALA will provide open access to educational resources (in English and Spanish), multi-tiered virtual mentorship, and collaboration opportunities to Latin American students at partner academic institutions; helping students reach their highest potential (to climb), while building a network that grows with their community goals (to scale up).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.