Innovative Self-Centering Braces for Advanced Seismic Performance

屈曲约束支撑目前被用作高地震区建筑物的主要抗侧力构件。在强烈地震动后，含有屈曲约束支撑的建筑物可能会永久变形，因此它们的修复可能不可行。由于需要开发具有自我中心且无永久变形的结构体系，本项目将研究创新的自中心屈曲约束支撑在建筑物中作为抗震装置的使用。提出的自定心防屈曲支撑由新型的钢管和安装超弹性形状记忆合金杆的锚固板组成，提供了一种具有可预测和稳定耗能的自定心机构。拟议研究的主要目标是进行实验和数值研究，为在实践中应用拟议的保护制度奠定坚实的基础。将对大型原型自心屈曲约束支撑进行试验，以验证预期的支撑性能，并检验关键支撑参数的影响。将开发数值模型并验证其在参数组件研究和支撑框架地震模拟中的使用。试验和数值研究的结果将被用于制定抗震结构体系中实际应用自中心屈曲约束支撑的设计和制造指南。所提出的自中心屈曲约束支撑体系的使用具有显著限制建筑结构的地震破坏和经济损失的潜力。建议的保护系统可以很容易地取代传统的钢支撑或屈曲约束支撑，这种易用性将使其对执业工程师和承包商特别有吸引力。自中心屈曲约束支撑框架系统的设计可以承受大地震，几乎没有破坏，通过为建筑物提供即时的入住率，有可能对受地震影响的社区产生重大的更广泛的影响。该项目还将为本科生和研究生提供独特的学习机会和培训，因为他们积极参与这一先进保护系统的开发。

Buckling-restrained braces are currently being used as primary lateral-force resisting elements for buildings in high seismic regions. After strong ground shaking buildings containing buckling-restrained braces are likely to be permanently deformed and thus their repairs may not be feasible. Since it is desirable to develop structural systems that self-center and have no permanent deformation, this project will investigate the use of innovative self-centering buckling-restrained braces as seismic protective devices in buildings. The proposed self-centering buckling-restrained brace consists of a novel configuration of steel tubes and anchorage plates installed with super-elastic shape-memory alloy rods to provide a self-centering mechanism with predictable and stable energy dissipation. The primary objective of the proposed research is to conduct experimental and numerical studies that establish a sound basis for application of the proposed protective system in practice. Large-scale prototype self-centering buckling-restrained braces will be tested to verify the anticipated brace behavior and to examine the effect of critical brace parameters. Numerical models will be developed and validated for use in parametric component studies and braced frame earthquake simulations. The results from the experimental and numerical studies will be used to develop design and fabrication guidelines for practical implementation of self-centering buckling-restrained braces in earthquake-resistant structural systems.The use of the proposed self-centering buckling-restrained brace system has the potential to significantly limit earthquake damage and economic loss in building structures. The proposed protective system can be easily substituted for conventional steel braces or buckling-restrained braces, and this ease of use will make it especially attractive to practicing engineers and contractors. The use of self-centering buckling-restrained braced frame systems, which can be designed to withstand large earthquakes with little to no damage, has the potential for significant broader impact on earthquake affected communities by providing buildings with immediate occupancy performance. This project will also provide unique learning opportunities and training to undergraduate and graduate students as they actively participate in the development of this advanced protective system.