CAREER: Mitigation of Seismic Risk to Critical Building Contents via Optimum Nonlinear 3D Isolation

该学院早期职业发展（CAREER）补助金将推进建筑物抗震隔离解决方案的设计，分析和实施，克服现有的限制，以确保必要设施中关键任务设备的震后功能。为了公众的福利和安全，紧急反应中心和医院等基本设施必须在地震期间和地震后保持运转。地震隔离系统，如滚动隔离平台，是保护这些设施内的单个部件或设备组的可行手段。然而，这些系统，目前遭受有限的位移能力和垂直激励没有保护，降低其性能下强烈的三向地震引起的地板运动。该研究项目将开发一个多目标，风险知情的框架来优化三维隔震系统，推进使用该框架设计的被动三维隔震系统的数学建模，并在三向地震荷载下实验验证预测的性能。这些新的知识，加上改进的设计工具，将使执业工程师更好地了解这些系统的行为，并寻求创新的战略，以减轻对重要设备的损害，从而减少国家的基本设施的脆弱性。该研究计划将被编织到旨在促进工程多样性的教育活动中，并通过低成本的教育摇表模块为K-12，本科生和研究生创造实践教育机会。 项目数据将在自然灾害工程研究基础设施数据库（https：//www.example.com）存档并公开提供。www.DesignSafe-ci.org 该项目有助于国家科学基金会在国家地震灾害减少计划中的作用。 这项研究的总体目标是通过更深入地了解其基础物理来推进3D隔震策略，并优化，评估和验证其性能。本研究将回答以下基本问题：（a）如何在从频繁到罕见的各种强度的三向地震激励下可靠地确保基本设施及其内容的不间断运行;以及（B）如何通过创新材料和优化方法增强设备隔震系统固有的性能。该项目的具体任务是：（1）表征关键建筑物内容的三维地震危害，并为这些组件定义基于风险的性能目标;（2）发现并实现由滚动摆轴承和准零刚度隔震器组成的被动三维隔震系统的最佳非线性恢复力和阻尼力，该系统表现出基于响应的适应性;（3）实验性地验证这些保护系统的基于物理的数学模型，用于设计中以捕获在地震载荷下发生的复杂行为;以及（4）建立一个设计框架，以促进这一概念直接转化为工程实践。该奖项反映了NSF的法定使命，并被认为是值得的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，

This Faculty Early Career Development (CAREER) grant will advance the design, analysis, and implementation of seismic isolation solutions for buildings, overcoming existing limitations to ensure post-earthquake functionality of mission-critical equipment in essential facilities. Essential facilities, such as emergency response centers and hospitals, must remain operational during and after an earthquake for the public welfare and safety. Seismic isolation systems, such as rolling isolation platforms, are a viable means of protecting individual components or groups of equipment within such facilities. These systems, however, presently suffer from limited displacement capacity and no protection from vertical excitations, diminishing their performance under strong tri-directional earthquake-induced floor motions. This research project will develop a multi-objective, risk-informed framework to optimize 3D isolation systems, advance the mathematical modeling of passive 3D isolation systems designed using the framework, and experimentally verify the predicted performance under tri-directional seismic loading. This new knowledge, coupled with improved design tools, will allow practicing engineers to better understand the behavior of these systems and to pursue innovative strategies to mitigate damage to vital equipment, thus reducing the vulnerability of the nation's essential facilities. The research plan will be woven into educational activities aimed at promoting diversity in engineering and creating hands-on educational opportunities for K-12, undergraduate, and graduate students through a low-cost, educational shake table module. Project data will be archived and made publicly available in the Natural Hazards Engineering Research Infrastructure Data Depot (https://www.DesignSafe-ci.org). This project contributes to the National Science Foundation role the National Earthquake Hazards Reduction Program. The overarching objective of this research is to advance 3D seismic isolation strategies through a deeper understanding of their underlying physics and to optimize, evaluate, and validate their performance. This research will answer fundamental questions related to (a) how the uninterrupted operation of essential facilities and their contents can be reliably ensured under tri-directional earthquake excitations of various intensities from frequent to rare events, and (b) how the performance capacity inherent to equipment isolation systems can be augmented with innovative materials and optimization approaches. The specific tasks of the project are aimed at: (1) characterizing 3D seismic hazards to critical building contents and defining risk-based performance objectives for these components; (2) discovering and realizing optimum nonlinear restoring and damping forces for passive 3D isolation systems composed of rolling pendulum bearings and quasi-zero stiffness isolators that exhibit response-based adaptation; (3) experimentally validating physics-based mathematical models of these protective systems for use in design to capture the complex behavior that occurs under seismic loading; and (4) establishing a design framework to facilitate the direct transfer of this concept to engineering practice.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.