NEESR-SG: Development of Next Generation Adaptive Seismic Protection Systems

NEESR-SG：下一代自适应地震防护系统的开发

• 批准号: 0830391
• 负责人: Satish Nagarajaiah
• 金额: $ 159.11万
• 依托单位: William Marsh Rice University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-09-01 至 2013-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0830391&HistoricalAwards=false
• 关键词: NEESR; SG; Development; Next; Generation

This award is an outcome of the NSF 08-519 program solicitation George E. Brown, Jr. Network for Earthquake Engineering Simulation (NEES) Research (NEESR) competition and includes Rice University as the lead institution with subawards to the University at Buffalo, Rensselaer Polytechnic Institute, University of California-Los Angeles, and California State University-Fresno. Conventionally designed structural frame systems develop significant inelastic deformations under strong earthquakes, leading to inelastic hysteretic behavior, stiffness and strength degradation, increased interstory drifts, and damage with residual drift. Passive seismic protection systems in the form of supplemental damping devices have emerged as an effective approach for reducing response and limiting damage by shifting the inelastic energy dissipation from the framing system to the dampers. However, such dampers do not generally provide self-centering stiffness capability or counter stiffness degradation. Recent investigations have shown that a combination of adaptive stiffness and damping (ASD) devices can provide substantial response modification, particularly during near-fault pulse-type earthquakes. ASD devices offer structural response modification capability by optimally varying the restoring forces (stiffness) linked to the frequencies of vibration and dissipative forces (damping) that govern the behavior of a structural dynamic system. To date, adaptive stiffness systems have received relatively little attention as compared to supplemental damping systems and thus represent a significant gap in earthquake engineering. Hence, development of new ASD devices is necessary to shift the energy dissipation and associated stiffness variations from the structural system to the ASD devices to reduce damage in frames, eliminate residual interstory drift, and provide self-centering capability. The research vision of this project is to develop the next generation of seismic protection systems by combining a new class of self-centering adaptive stiffness systems with highly efficient energy dissipation. The goal is to mimic the behavior of actively controlled devices by developing self-contained semi-active ASD devices with feedback and passive ASD devices with internal hydraulic feedback. The core strategy involves a comprehensive analytical and experimental investigation of potential active, semiactive, and passive systems followed by the synthesis and development of practical adjustable passive systems and self-contained semi-active systems for implementation in practical structures. Such an approach is consistent with that adopted in the defense industry and is expected to result in widespread application of ASD systems in civil structures. The project is expected to advance the state-of-the-art of increased resilience through structural response modification, contributing to earthquake hazard mitigation and expedient post earthquake recovery (due to easy replacement of ASD systems). The project will broadly impact earthquake engineering practice through educational outreach and wide dissemination of research findings through the project web site. Additionally, the project will have a significant impact on students from underrepresented groups through active involvement of a Hispanic Serving Institution. This project will utilize the NEES equipment site and experimental facilities at the University at Buffalo to achieve its goals. Following the experiments, all data from this project will be made available through the NEES data repository (http://www.nees.org).

这个奖项是一个结果的NSF 08-519计划征求乔治E。小布朗地震工程模拟网络（NEES）研究（NEESR）竞赛，包括莱斯大学作为牵头机构，子奖项授予布法罗大学、伦斯勒理工学院、加州大学洛杉矶分校和加州州立大学弗雷斯诺分校。常规设计的结构框架体系在强震作用下会产生显著的非弹性变形，导致非弹性滞回行为、刚度和强度退化、层间位移增加以及残余位移破坏。以附加阻尼装置形式出现的被动地震保护系统已经成为通过将非弹性能量耗散从框架系统转移到阻尼器来减少响应和限制损害的有效方法。然而，这种阻尼器通常不提供自定心刚度能力或对抗刚度退化。最近的调查表明，自适应刚度和阻尼（ASD）装置的组合可以提供实质性的响应修改，特别是在近断层脉冲型地震期间。ASD装置通过最佳地改变与控制结构动态系统行为的振动频率和耗散力（阻尼）相关的恢复力（刚度）来提供结构响应修改能力。到目前为止，自适应刚度系统已收到相对较少的关注相比，补充阻尼系统，因此代表了一个显着的差距，在地震工程。因此，有必要开发新的ASD装置，以将能量耗散和相关刚度变化从结构系统转移到ASD装置，以减少框架中的损坏，消除残余层间漂移，并提供自定心能力。 该项目的研究愿景是通过将新型自定心自适应刚度系统与高效耗能相结合，开发下一代地震保护系统。我们的目标是通过开发具有反馈的自包含半主动ASD装置和具有内部液压反馈的被动ASD装置来模仿主动控制装置的行为。核心策略包括对潜在的主动、半主动和被动系统进行全面的分析和实验研究，然后综合和开发实用的可调被动系统和自给式半主动系统，以在实际结构中实施。这种方法与国防工业中采用的方法是一致的，预计将导致ASD系统在民用结构中的广泛应用。该项目预计将通过结构反应修改来提高最新的恢复能力，有助于减轻地震灾害和快速的地震后恢复（由于易于更换ASD系统）。该项目将通过教育推广和通过项目网站广泛传播研究成果，对地震工程实践产生广泛影响。此外，该项目将通过西班牙裔服务机构的积极参与，对代表性不足的群体的学生产生重大影响。该项目将利用布法罗大学的NEES设备场地和实验设施来实现其目标。在实验之后，将通过NEES数据储存库（http：//www.example.com）提供该项目的所有数据。www.nees.org