基于防屈曲SMA自复位阻尼器的功能可恢复钢框架抗震性能研究

Steel frames are widely used in our country, but have a relatively low seismic resilience. Pure frames sustained earthquakes by forming plastic deformation in the main components, but tend to generate excessive residual deformation after earthquakes, lending to significant economic and social loss. Therefore, reducing residual deformation is an effective method to raise seismic resilience. This proposal aims to develop an innovative NiTi-SMA self-centering damper, and to explore the theory of enhancing seismic resilience by selecting steel frames as example. The proposed damper is based on buckling-restrained SMA bars, having the merits of high strength capacity and robust vibration control capability upon strong earthquakes or low temperature. With tests, simulations and analyses on material, components and structures, this research is to study the mechanism and seismic vibration control of the damper, to built the fragility curves at various temperatures, and to develop a general performance based seismic design method. The research will not only enrich the studies on SMA-based vibration control, but also improve the theory and technique of self-centering structures. As well, this research is beneficial to the post-event recovery of earthquake-attacked region, which offers long-term social benefits.

钢框架结构在我国有广泛的应用，但是震后功能可恢复性不高。纯框架结构通过主体构件的塑性变形抵御地震，但是在震后易产生严重的残余变形，导致沉重的经济成本和社会损失。因此，消除残余变形是提升震后功能的有效途径之一。本项目拟以防屈曲镍钛SMA自复位阻尼器为切入点，选取钢框架结构为研究对象，阐明该新型阻尼器提升结构震后功能的机理。拟提出的阻尼器以防屈曲SMA棒材为核心构件，不仅具有较高的双向承载力，而且在强震和低温下都能保持良好的减震鲁棒性。结合材料-构件-结构三个层次的试验、模拟和分析，揭示该阻尼器的工作机理和减震效果，形成温度关联的地震易损性曲线，提出普适性高的抗震性能化设计方法。不仅将丰富SMA消能减震的研究，而且能够提高自复位结构研究的理论水平和技术手段，对整个抗震减震研究领域也将产生积极的学术影响。本项目的研究成果将有助于恢复地震受灾地区人们的生活和生产，具有深远的社会效益。

本项目以抗震结构为研究对象，旨在通过减小震后残余变形来提升抗震韧性。为此，提出了以防屈曲SMA型材为核心构件的新型自复位阻尼器。试验结果表明，该新型阻尼器不仅具有较高的双向承载力，而且在大变形和低温下都能保持良好的减震鲁棒性。在体系层面，选取多层钢框架结构为研究对象，系统阐述了该新型阻尼器提升结构抗震韧性的机理，建立了温度关联的地震易损性曲线，提出了普适性较高的抗震性能化设计方法。本项目丰富了基于SMA的消能减震研究，而且推动了自复位结构的抗震理论水平和技术手段，相关研究成果有助于地震受灾地区的震后恢复。依托该项目发表高水平期刊论文19篇，授权专利10余项，培养硕士研究生4名。