消能摇摆钢框架结构抗震性能的影响因素与设计方法

消能摇摆钢框架结构包含主体钢框架结构、摇摆结构和耗能阻尼器三部分。刚度较大的摇摆结构可以使主体钢框架在地震作用下发生均匀的层间变形，抑制薄弱层产生。布设于摇摆结构底部的阻尼器，能够耗散地震动能量，减小整体结构的地震反应，提高结构的抗震性能。文中对消能摇摆钢框架结构抗震性能的影响因素进行参数分析，并基于我国建筑抗震设计规范的原则提出了抗震设计方法。根据消能摇摆钢框架结构的受力机理，提出简化分析模型，通过弹塑性地震反应分析，验证简化模型的有效性。基于简化分析模型对无量纲参数进行参数分析，根据各参数的影响规律得到无量纲参数的建议范围。结合我国“三阶段”抗震设防要求，提出消能摇摆钢框架结构的设计方法，并结合算例进行验证。研究表明，消能摇摆钢框架结构抗震性能良好，设计合理的摇摆结构与阻尼器能够抑制钢框架的薄弱层、减小结构的地震反应。

Influencing factors of seismic behavior and design procedure on steel frames coupled with rocking structure and dampers

Steel frames coupled with rocking structure and dampers consist of steel frame, rocking structure and energy-dissipative dampers. Rocking structures with significant flexural stiffness can ensure inter-story drift of steel frames to distribute uniformly and prevent weak stories. The dampers at bottom of the rocking structure can dissipate earthquake energy, decrease seismic response and improve the seismic performance of the whole structure. Parametric study of steel frames coupled with rocking structure and dampers was conducted and seismic design procedure was proposed based on basic principles of Chinese seismic design codes of building structures. A simplified analytical model was proposed based on the force transfer mechanism of steel frames coupled with rocking structure and dampers. Based on seismic analysis with elastoplastic model, the proposed analytical model was proved to be applicable. The dimensionless design parameters were summarized and the reasonable range of value was recommended based on the parametric study of simplified models. Considering the requirements of Chinese design codes of ‘three-stage’ seismic design, the practical design method of steel frames coupled with rocking structure and dampers was proposed and verified by a study case. It is concluded that the steel frames coupled with rocking structure and dampers have favorable seismic performance to prevent weak story failure mode and can mitigate seismic response when the rocking structure and dampers are designed reasonably.