NEESR: Next Generation Dissipation Guidelines for New and Existing Structures using the NEES Database

该奖项的研究目标是表征与地震中建筑物的损坏无关的能量耗散能力。该项目采取多管齐下的方法来实现这一目标。在分析方面，研究了激励频率对识别的等效阻尼的影响(因为实际的机理不太可能是粘性的)，以及各种识别算法的采样率和自由参数如何影响极点的计算虚部，从而确定等效阻尼值。由于这项工作是在确定与非破坏性机制相关的耗散，该项目着眼于数据驱动的方法，将观察到的反应归类为准线性或显著的非线性。该项目包括开发一个程序，基于控制理论中的经典跟踪问题，将非破坏性耗散与总耗散分开。来自小乔治·E·布朗的数据库。地震工程模拟网络(NEES)项目仓库用于验证分析研究，并辅之以现场建筑物测量的数据，用于制定新结构和现有结构的阻尼比规定准则。该项目的数据将被存档，并通过位于http://www.nees.org.的NEES项目仓库数据库向公众提供该项目是设计有效手段提供结构设计的努力的一部分，这些结构设计不仅为大地震提供生命保护，而且将暴露在各种规模的地震事件中的经济损失降至最低。尽管在过去的几十年里，包括循环响应在内的弹性和非弹性行为的计算能力和建模能力有了显著的提高，但自1960年S关于非破坏性相关耗散的规范标准以来，几乎没有变化，该标准在预测中小地震的反应方面发挥了重要作用。该项目利用NEES项目仓库数据库中目前可用的数据来限制对地震工程中与非损害相关的耗散问题的分析研究。该奖项包括一项教育推广倡议，将研究与本科生和高中生的教育相结合。该奖项是国家减少地震灾害计划(NEHRP)的一部分。

The research objective of this award is to characterize energy dissipation capacity not associated with damage in buildings subjected to earthquakes. The project takes a multi-prong approach to attain this objective. On the analytical side, it examines how identified equivalent damping is affected by excitation frequency content (since the actual mechanism is unlikely viscous) and how sampling rate and the free parameters of various identification algorithms affect the computed imaginary part of the poles, which determines the equivalent damping. Because the effort is on identifying dissipation associated with non-damaging mechanisms, the project looks at data-driven means to classify observed responses as being quasi-linear or notably non-linear. The project includes development of a procedure, based on the classical tracking problem from control theory, to separate the non-damaging dissipation from the total dissipation. The database from the George E. Brown, Jr. Network for Earthquake Engineering Simulation (NEES) Project Warehouse is used to validate the analytical studies and, complemented with data measured in buildings in the field, is used to formulate guidelines for specifying damping ratios for new and existing structures. Data from this project will be archived and made available to the public through the NEES Project Warehouse data repository at http://www.nees.org. The project is part of efforts to devise efficient means to provide structural designs that not only provide life protection for large earthquakes but also minimize economic losses associated with exposure to seismic events of all sizes. Although computational capability and modeling of elastic and inelastic behavior, including cyclic response, has improved notably in the past few decades, little change has taken place since the 1960's on criteria for the specification of non-damaging related dissipation, which plays an important role for predicting response for small and moderate events. This project leverages data that is currently available in the NEES Project Warehouse data repository to constrain analytical research on the question of non-damage related dissipation in seismic engineering. This award includes an educational outreach initiative that integrates the research with education for undergraduate and high school students. This award is part of the National Earthquake Hazards Reduction Program (NEHRP).