Development of Composite Yielding Dampers

复合材料屈服阻尼器的研制

• 批准号: 0099701
• 负责人: Christopher Higgins
• 金额: $ 10万
• 依托单位: Oregon State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-09-15 至 2005-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0099701&HistoricalAwards=false
• 关键词: Development; Composite; Yielding; Dampers

Passive control of structures is still evolving technologically, with increasing understanding of system behavior, response prediction methodologies, design guidance, and field experiences. Valuable information regarding behavior, design, and implementation of passive control systems is being developed in Japan due to their significant research investment in innovative passive control measures for protection of structures against both seismic and wind forces. One type of innovative passive controlsystem that has been developed recently in Japan is a type of yielding brace damper. The yielding brace contains a single steel plate with large ductility capacity and relatively low yield strength that is encased in a grout filled tube, but is not bonded to the grout. The key concept of the device is that yielding occurs in the encased steel plate equally for both tensile and compressive loading cycles and the system exhibits stable hysteretic energy dissipation capability. A new type of yielding device is proposed which builds on the economic advantages of the yielding brace, but allows tailoring the yielding element materials to achieve specific performance requirements and employs noncohesive media to confine the yielding elements. These two innovations combined provide controlled post-yield slope of the damper that maintains self-centering capability of a structure even during an extreme earthquake when the buildingframe may significantly yield and soften; provide a generally applicable confining technique that does not infringe on existing patents; eliminate high-precision design, detailing, and fabrication of devices at the debonding interface; lower damper cost; ease of repair/replacement of yielding elements after a damaging earthquake; enable inspection; and provide additional friction damping which may be beneficial for wind response mitigation. This new device is defined as a composite yielding damper (CY-damper).The combined attributes of CY-dampers may provide significant technical and economicadvantages over existing devices. A research program, integrating both experimental and analytical components, is proposed to investigate the application of CY-dampers for building structures. The primary objectives of the proposed research project are to: (1) develop prototype CY-dampers, (2) characterize the structural performance of individual CY-dampers and optimize damper properties, (3) determine the behavior ofbuilding frames with CY-dampers under varying magnitude earthquakes, (4) develop analytical models to describe the behavior of CY-dampers and CY-damped systems, and (5) provide guidance for the application of CY-dampers directed toward performance based design. These objectives will be achieved by working in collaboration with a team of Japanese researchers who are the primary developers of this system in Japan. Professional relationships and research collaboration are on-going between the researchers and significant resource and information exchange will take place throughout all phases of the proposed research program. Small and large-scale CY-damper tests under reversed cyclic loading are proposed. Parameters to be studied include: (1) application of different materials including combinations of high and low strength steels or other high-performance materials, (2) investigation of different confining materials and plate slenderness parameters, and (3) long term durability under high-cycle low-amplitude fatigue. A prototype multistory multibay steel frame building will be used to facilitate development of realistic test specimens and permit comparison between different damper designs. In concert with experimental tasks, analytical models will be produced which are compatible with available analysis programs and correlate experimentally observed response. Simplified and practical analysis methods including equivalent linearization techniques will be developed to predict response and develop practical design guidance.

随着对系统行为、响应预测方法、设计指导和现场经验的了解不断增加，结构的被动控制技术仍在不断发展。日本正在开发有关被动控制系统的行为、设计和实施的有价值的信息，因为他们在创新的被动控制措施方面进行了大量的研究投资，以保护结构免受地震和风力的影响。日本最近开发的一种创新的被动控制系统是一种屈服支撑阻尼器。屈服支撑由一块延性大、屈服强度相对较低的钢板包裹在灌浆筒内，但不与灌浆粘结。该装置的关键概念是，在拉伸和压缩加载循环中，包围钢板的屈服相同，并且系统具有稳定的滞回能量耗散能力。提出了一种新型的屈服装置，它在屈服支撑的经济优势的基础上，但允许定制屈服单元材料以达到特定的性能要求，并使用非粘性介质来限制屈服单元。这两项创新结合在一起，提供了可控的阻尼器屈服后斜率，即使在极端地震中，当建筑框架可能显著屈服和软化时，也能保持结构的自定心能力；提供一种普遍适用的限制技术，不侵犯现有专利；消除去粘接界面上设备的高精度设计、细节和制造；降低阻尼器成本；在破坏性地震后，易于修复/更换变形元件；使检验;并提供额外的摩擦阻尼，这可能有利于风响应的缓解。这种新装置被定义为复合屈服阻尼器（cy -阻尼器）。与现有设备相比，cy阻尼器的综合特性可以提供显着的技术和经济优势。提出了一种实验与分析相结合的研究方案，研究cy阻尼器在建筑结构中的应用。提出的研究项目的主要目标是：(1)开发原型cy -阻尼器，(2)表征单个cy -阻尼器的结构性能并优化阻尼器性能，(3)确定具有cy -阻尼器的建筑框架在不同震级地震下的行为，(4)开发描述cy -阻尼器和cy -阻尼系统行为的分析模型，以及(5)为cy -阻尼器在基于性能的设计中的应用提供指导。这些目标将通过与日本研究人员团队合作来实现，他们是该系统在日本的主要开发人员。研究人员之间的专业关系和研究合作正在进行，重要的资源和信息交流将在拟议研究计划的各个阶段进行。提出了反循环载荷下的小型和大型cy -阻尼器试验方案。研究的参数包括：(1)不同材料的应用，包括高低强度钢或其他高性能材料的组合；(2)不同围合材料和板长细比参数的研究；(3)高周低幅疲劳下的长期耐久性。一个多层多湾钢框架建筑的原型将被用来促进真实试验样本的发展，并允许不同阻尼器设计之间的比较。为了配合实验任务，将产生与现有分析程序兼容并与实验观察到的反应相关联的分析模型。简化和实用的分析方法，包括等效线性化技术将开发预测响应和开发实用的设计指导。