NEESR-SG: Self-Centering Damage-Free Seismic-Resistant Steel Frame Systems

项目摘要拟议项目将研究一系列创新的自定心（SC）钢框架系统，这些系统有可能承受目前公认的建筑物设计基准地震（DBE）而不会造成损坏。项目目标是： 发展 SC 钢框架系统抗震性能的基础知识；利用 George E. Brown, Jr. 地震工程模拟网络 (NEES) 的支持设施，对 SC 钢框架系统进行集成设计、分析和实验研究；为 SC 钢框架系统开发基于性能、可靠性的抗震设计程序和标准；与传统的抗震钢框架系统不同，传统的抗震钢框架系统会在 DBE 下产生显着的非弹性变形，从而导致严重的损坏和残余位移，而该项目开发的创新 SC 钢框架系统有可能避免 DBE 下的结构损坏，因为它具有以下几个特点：侧向力-漂移行为软化，而结构构件没有非弹性变形，因此不会造成结构损坏和残余位移；软化行为是通过在选定的后张连接处打开间隙而产生的（例如，框架的梁柱界面处的分离）；侧向力-漂移行为的延展能力可能相当大，并且不受材料延展能力的控制；地震荷载下的能量耗散不是来自主要结构构件的损坏，而是来自设计过程中指定的耗能元件，如果损坏可以更换。该项目范围包括九项研究任务和一些针对 SC 钢框架系统的教育、外展和传播活动。研究团队将为SC钢框架系统开发基于可靠性的抗震设计程序、系统概念和细节以及耗能元件；将开发传感器网络来监测和评估 SC 钢框架系统；并将使用 SC 钢框架系统设计原型建筑，对这些原型建筑进行非线性分析，并对原型建筑的样本进行大规模实验室模拟。该项目需要利用位于Lehigh的大型结构系统抗震性能模拟实时多向测试设施（RTMD）NEES设备场进行大规模地震模拟来实现其目标。将采用混合（伪动力）测试方法，必要时也会使用RTMD的实时混合测试方法和实时能力。项目团队是多组织的，包括Lehigh、普林斯顿和普渡大学大学，多学科且多样化。该团队包括来自台湾国家地震工程研究中心 (NCREE) 的国际参与人员，并将由来自美国和国际地震和结构工程界知名工程公司的人员组成的委员会提供建议。智力价值.. 先前对 SC 钢系统的研究已经证明了它们的潜力，但是，缺乏对其抗震行为和性能的全面了解。之前 NSF 资助的 SC 预制混凝土系统研究已经产生了知识，使这些创新系统能够付诸实践； SC 钢系统也需要类似的知识。拟议项目将提供有关 SC 钢系统行为和性能所需的基础知识，以及实施设计、制造和施工实践所需的实用知识。 SCsteel系统的主要创新点是：初始刚度与常规系统相似，在地震荷载作用下会发生软化，但不会产生主要结构构件的损坏、残余漂移以及相关的震后修复费用；通过设计耗能，而不是通过主要结构构件损坏。此外，创新项目的特点包括在开发系统本身的同时，为SC钢系统开发基于可靠性的综合设计程序和标准，以及开发用于损坏监测和评估的传感器网络，以避免昂贵的震后检查过程。更广泛的影响。新的SC钢框架系统有潜力承受DBE而不损坏，并且初始成本经济。因此，通过提高有关 SC 钢框架系统的知识，该项目预计将通过减少传统抗震系统通常巨大的震后损坏成本来产生显着的社会效益。此外，该项目还将通过教育参与拟议项目的研究生和本科生、注册该项目开发的课程的学生以及通过该项目网站接触到的学生来影响地震工程人员。从业者将通过传播计划和项目网站接受教育。

PROJECT SUMMARYThe proposed project will investigate a family of innovative self-centering (SC) steel frame systems withthe potential to withstand the currently accepted design basis earthquake (DBE) for buildings without damage.The project goals are: to develop fundamental knowledge of the seismic behavior of SC steel frame systems; toconduct integrated design, analysis, and experimental research on SC steel frame systems, using the enablingfacilities of the George E. Brown, Jr. Network for Earthquake Engineering Simulation (NEES); to developperformance-based, reliability-based seismic design procedures and criteria for SC steel frame systems; and to educate students and practitioners with fundamental and practical knowledge about SC steel frame systems.Unlike conventional earthquake-resistant steel frame systems that are designed to develop significantinelastic deformations under the DBE, resulting in significant damage as well as residual drift, the innovativeSC steel frame systems developed by the project have the potential to avoid structural damage under the DBEas a result of several features: the lateral force-drift behavior softens without inelastic deformation of thestructural members, and, therefore, without the resulting structural damage and residual drift; the softeningbehavior is created by gap opening at selected post-tensioned connections (e.g., a separation at the beamcolumn interfaces of the frame); the ductility capacity of the lateral force-drift behavior can be quite large and is not controlled by material ductility capacity; and energy dissipation under seismic loading is not from damage to main structural members, but from energy dissipation elements that are specified in the design process and can be replaced if damaged.The project scope includes nine research tasks and a number of educational, outreach, and disseminationactivities focused on SC steel frame systems. The research team will develop reliability-based seismic designprocedures, system concepts and details, and energy dissipation elements for SC steel frame systems; willdevelop sensor networks to monitor and assess SC steel frame systems; and will design prototype buildingsusing SC steel frame systems, perform nonlinear analyses of these prototype buildings, and conduct large-scale laboratory simulations on specimens derived from the prototype buildings. The project requires the use of the Real-Time Multidirectional Testing Facility for Seismic Performance Simulation of Large-Scale Structural Systems (RTMD) NEES equipment site at Lehigh for large-scale earthquake simulations to achieve its goals.The hybrid (pseudo-dynamic) testing method will be utilized, and when needed, the real-time hybrid testing method and real-time capabilities of the RTMD will be used as well.The project team is multi-organizational, involving Lehigh, Princeton, and Purdue Universities, multidisciplinary and diverse. The team includes international participation from the National Center for Research on Earthquake Engineering (NCREE) in Taiwan, and will be advised by a board of individuals fromengineering firms well known in the US and international earthquake and structural engineering communities. Intellectual Merit.. Prior research on SC steel systems has demonstrated their potential, however,comprehensive knowledge of their seismic behavior and performance is lacking. Prior NSF-funded researchon SC precast concrete systems has produced knowledge that is enabling these innovative systems to moveinto practice; similar knowledge is needed for SC steel systems. The proposed project will provide the neededfundamental knowledge on the behavior and performance of SC steel systems, as well as practical knowledgeneeded for implementation into design, fabrication, and construction practice. The main innovations of SCsteel systems are: initial stiffness similar to conventional systems, with softening under earthquake loading, but without main structural member damage, residual drift, and the related post-earthquake repair costs; and energy dissipation by design, not by main structural member damage. In addition, innovative project features include the development of reliability-based, comprehensive design procedures and criteria for SC steel systems in parallel with the development of the systems themselves, and the development of sensor networks for damage monitoring and assessment to avoid costly post-earthquake inspection processes.Broader Impacts.. The new SC steel frame systems have the potential to withstand the DBE without damage,as well as to be economical in initial cost. Thus, by advancing knowledge about SC steel frame systems, theproject is anticipated to have significant societal benefits by reducing the often-enormous post-earthquakedamage costs of conventional earthquake-resistant systems. In addition, the project will impact the earthquake engineering workforce by educating graduate and undergraduate students participating in the proposed project, students enrolled in the course developed by the project, and students reached by the project web site. Practitioners will be educated through the dissemination plan and project web site.