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

项目概述：拟议的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设计基础地震（DBE）而不会损坏。该项目的目标是：发展SC钢框架体系抗震性能的基本知识；利用George E. Brown, Jr.地震工程模拟网络（NEES）的支持设施，对SC钢框架系统进行综合设计、分析和实验研究；制定基于性能和可靠性的SC钢框架体系抗震设计程序和规范；并向学生和从业人员传授SC钢框架系统的基础和实践知识。与传统的抗震钢框架系统不同，传统的抗震钢框架系统在DBE作用下会产生显著的非弹性变形，导致严重的破坏和残余的漂移，该项目开发的创新的vesc钢框架系统有可能避免dbea作用下的结构破坏，因为它具有以下几个特点：侧向力-漂移行为在没有结构构件非弹性变形的情况下软化，因此没有导致结构损伤和残余漂移；通过在选定的后张连接处打开间隙（例如，框架的梁柱界面处的分离）创建软化行为；侧向力-漂移行为的延性能力相当大，不受材料延性能力的控制；地震荷载作用下的耗能不是主要结构构件的损坏，而是设计过程中指定的耗能单元损坏后可以更换的耗能单元。项目范围包括九项研究任务和一些以SC钢框架系统为重点的教育、推广和传播活动。研究小组将开发基于可靠性的抗震设计程序，系统概念和细节，以及SC钢框架系统的耗能元件；将开发传感器网络，以监测和评估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。该项目需要使用位于Lehigh的大型结构系统地震性能模拟实时多向测试设施（RTMD） NEES设备进行大规模地震模拟，以实现其目标。将采用混合（伪动态）测试方法，并在需要时利用实时混合测试方法和RTMD的实时能力。项目团队是多组织的，包括里海大学、普林斯顿大学和普渡大学，多学科和多样化。​知识价值. .先前对SC钢体系的研究已经证明了它们的潜力，然而，缺乏对其抗震行为和性能的全面了解。先前nsf资助的SC预制混凝土系统的研究已经产生了知识，使这些创新的系统进入实践；SC钢系统也需要类似的知识。拟议的项目将提供SC钢系统的行为和性能所需的基本知识，以及在设计、制造和施工实践中实施所需的实用知识。scl钢结构体系的主要创新是：初始刚度与常规体系相似，在地震荷载作用下软化，但没有主要结构构件损伤、残余漂移和相关的震后修复费用；且能量耗散由设计决定，不受主要结构构件破坏影响。此外，创新项目的特点包括在开发SC钢系统的同时，开发基于可靠性的综合设计程序和标准，以及开发用于损伤监测和评估的传感器网络，以避免昂贵的地震后检查过程。更广泛的影响。新的SC钢框架系统具有承受DBE而不损坏的潜力，并且在初始成本上是经济的。因此，通过提高对SC钢框架系统的了解，该项目预计将通过减少传统抗震系统通常巨大的震后破坏成本而产生显著的社会效益。此外，该项目将通过教育参与拟议项目的研究生和本科生、参加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，对地震工程劳动力产生影响。通过传播计划和项目网站对从业人员进行教育。

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.