NEESR-CR - Innovative Seismic Retrofits for Resilient Reinforced Concrete Buildings

该奖项是 NSF 09-524 项目征集“George E. Brown, Jr. 地震工程模拟 (NEES) 研究网络 (NEESR)”竞赛的结果，包括佐治亚理工学院（牵头机构）、霍华德大学（subaward）和莱斯大学（subaward）。该项目将利用加州大学洛杉矶分校运营的 NEES 移动振动台。项目团队将评估具有重心和/或高阻尼功能的新型创新系统的功效，并开发其设计和实施框架，以改造钢筋混凝土 (RC) 建筑，以提高抗震性能。目标是通过创新的大规模现场测试来验证 RC 建筑的新型改造。将研究五种改造措施，包括新型支撑系统、梁柱连接元件或柱包裹。这些系统的共同优势特征包括易于应用（几乎不需要重型机械）、可扩展性和适应性、被动性以及在整个生命周期中几乎不需要维护。此外，与传统的改造方法相比，这些系统的目标是在最小损坏、增强的事后功能和提高成本效益方面提供改进的抗震性能。在创新系统中使用先进材料将改善 RC 建筑的抗震改造，由于其高效的设计、最少的维护或安装中断以及更高的成本效益，这些建筑可能会得到更广泛的采用。 该研究包括一系列独特的多尺度实验，以及详细的有限元模拟、脆弱性分析和成本效益研究。研究、教育和推广计划包括以下关键组成部分：(1) 使用 NEES 移动振动台对创新改造系统（许多基于形状记忆合金）进行首次全尺寸系统级验证； (2) 与经验丰富的设计专业人员合作，基于规范设计改造措施； (3) 使用无线传感器的损坏检测方法，可投射有关创新改造状况和系统响应的详细信息； (4) 经过改造和未经改造的建筑物的详细脆弱性分析或脆弱性模型； (5) 成本效益和生命周期成本分析，为决策者提供最佳建筑改造信息； （6）与加拿大舍布鲁克大学进行缩小规模系统级测试的国际合作，以及与台湾大学和韩国弘益大学进行中等规模测试的国际合作； (7) 影响各个级别（K-12、大学和行业）的综合外展和教育计划； (8) 专注于与行业领导者进行技术转让的研讨会。智力成果：这项研究基于一系列多规模组件和全规模系统级现场测试，首次对高性能系统进行了大规模验证。将进行详细的分析建模和脆弱性分析，以评估各种创新改造对降低 RC 建筑地震脆弱性的影响。将建立一个框架，涵盖智能传感和结构损伤状态估计、脆弱性建模、性能评估和改装钢筋混凝土建筑的成本效益研究。新系统的验证预计将通过创新设计、材料使用和实施来改变当前建筑物抗震改造的方法，从而在性能（抗震和生命周期）方面取得显着进步。 更广泛的影响：拟议的研究、教育和推广计划的更广泛影响有四重。首先，新颖的多尺度测试加上详细的分析，将为此类高性能系统提供第一个已知的系统级验证。其次，所提议的改造所带来的效率、成本效益和最小的干扰可以产生可广泛应用的卓越改造方法，以提高全国范围内的建筑性能。第三，与行业合作伙伴的合作以及在实际结构中进行改造的现场测试将解决实施的现实挑战并简化向实践的转移。一系列研讨会将汇集学者、研究人员和工业界，以推进抗震建筑改造创新系统的转移。 第四，多方面的教育计划解决了改善高中科学和工程课程的需要，同时解决了在 STEM（科学、技术、工程和数学）领域攻读学位的学生人数不足的问题。该项目的数据将被存档并通过 NEES 数据库向公众提供。 该奖项是国家地震减灾计划（NEHRP）的一部分。

This award is an outcome of the NSF 09-524 program solicitation "George E. Brown, Jr. Network for Earthquake Engineering Simulation (NEES) Research (NEESR)" competition and includes the Georgia Institute of Technology (lead institution), Howard University (subaward), and Rice University (subaward). The project will utilize the NEES mobile shakers operated by the University of California, Los Angeles.The project team will evaluate the efficacy of a new class of innovative systems with recentering and/or high damping capabilities, and develop a framework for their design and implementation to retrofit reinforced concrete (RC) buildings to improve seismic performance. The goal is to validate, via innovative large scale field testing, a new class of retrofits for RC buildings. Five retrofit measures will be investigated, consisting of novel bracing systems, beam-column connection elements, or columns wraps. Common advantageous characteristics of the systems include the ease of application (requiring little-to-no heavy machinery), scalability and adaptability, passive nature, and need for little-to-no maintenance through the life-cycle. Furthermore, these systems aim to provide improved seismic performance in terms of minimal damage, enhanced post-event functionality, and improved cost-benefit compared to traditional retrofit approaches. The use of advanced materials in innovative systems will result in improved seismic retrofits for RC buildings that may find more widespread adoption due to their efficient design, minimal maintenance or disruption for installation, and enhanced cost-effectiveness. The research includes a series of unique multi-scale experiments, coupled with detailed finite element simulations, fragility analyses, and cost-benefit studies. Research, education, and outreach plans include the following key components: (1) first of its kind full-scale system-level validation of innovative retrofit systems (many based on shape memory alloys) using the NEES mobile shakers; (2) code-based designs of retrofit measures, in collaboration with experienced design professionals; (3) damage detection approaches using wireless sensors that project detailed information on the condition of the innovative retrofits, and the system response; (4) detailed fragility analyses, or vulnerability models, of buildings with and without retrofit; (5) cost-benefit and life-cycle cost analyses to inform decision-makers on optimal building retrofits; (6) international cooperation on reduced-scale system-level tests with Sherbrooke University in Canada, and medium-scale testing at National Taiwan University, and Hongik University (Korea); (7) a comprehensive outreach and education program impacting all levels (K-12, college, and industry); and (8) workshops focused on technology transfer with industry leaders.Intellectual Merit: This research provides the first large-scale validation of high performance systems based on a series of multi-scale component and full-scale system-level field tests. Detailed analytical modeling and fragility analyses will be performed to assess the impact of various innovative retrofits on reducing the seismic vulnerability of RC buildings. A framework will be established, ranging from smart sensing and structural damage state estimation, to fragility modeling, performance assessment, and cost-benefit studies of retrofitted RC buildings. The validation of the new systems are expected to provide a marked advance in performance (seismic and life-cycle) through innovative design, material usage, and implementation to transform current approaches for seismic retrofit of buildings.Broader Impacts: The broader impacts of the proposed research, education, and outreach program are four-fold. First, the novel multi-scale testing, coupled with detailed analysis, will provide the first known system-level validation of such high performance systems. Second, the efficiency, cost-effectiveness, and minimal disruption caused by retrofits proposed can result in superior retrofit approaches with broad application to improve building performance nationwide. Third, the collaboration with industry partners and field testing of retrofits in real structures will address realistic challenges of implementation and streamline transfer to practice. A series of workshops will bring together academics, researchers, and industry to advance the transfer of innovative systems for seismic building retrofit. Fourth, a multi-faceted education program addresses the need to improve high school science and engineering curriculum, while addressing the lack of underrepresented students pursuing degrees in the STEM (science, technology, engineering, and mathematics) arena.Data from this project will be archived and made available to the public through the NEES data repository. This award is part of the National Earthquake Hazards Reduction Program (NEHRP).