（罗马第三大学建筑系， 罗马 00146）

［摘要］研究了如何通过被动耗能方式对既有框架进行抗震加固。提出了一个基于能力谱和位移控制的迭代设计流程，并结合既有中心支撑钢框架结构讨论了该设计流程在实际应用中的有效性。该设计流程能够用于基于不同性能目标、采用任何类型的耗能装置进行抗震加固。在加固时采用的屈曲约束支撑用来防止结构构件和非结构构件的破坏。采用了传统的单模态Pushover分析（荷载和第一阶模态成正比）和多模态Pushover分析对既有框架结构的抗震加固进行分析。分析发现，对于中高层框架混凝土结构房屋（30m以上），耗能支撑设计过程中采用多模态Pushover分析比单模态Pushover分析结果更有效；然而采用屈曲约束支撑进行抗震加固后，房屋刚度变得规则，此时单模态Pushover分析和多模态Pushover分析得到的结果差别不大。

［关键词］耗能支撑; 地震工程; 能量耗散; 抗震加固

中图分类号：TU352.1      文献标识码：A      文章编号：1002-848X(2014)07-0015-06

Seismic retrofitting of reinforced concrete frame and concentric braced steel buildings with dissipative bracings

A.V. Bergami,  Xu Liu,  Zhihao Zhou,  C. Nuti

 (Department of Architecture, Roma Tre University, Rome 00146, Italy)

Abstract: Seismic retrofitting of existing frame structures by means of passive energy dissipation was presented. An iterative displacement-based procedure, based on capacity spectrum was described and some applications were discussed. The general procedure had also been discussed referring to the case of existing steel concentric braced frame structures (CBF). The procedure can be used with any typology of dissipative device and for different performance targets. The procedure had been applied, with both traditional Pushover (load profile proportional to first mode) and multimodal Pushover, to an existing RC frame building. In the application presented the buckling restrained braces had been used in order to prevent damages to both the structure and non structural elements. The use of multimodal Pushover proves to be more effective than Pushover based on single mode in case of medium rise RC frame building (higher than 30 metres) but, once this building is retrofitted, and therefore regularized, with a bracing system, the difference between using the monomodal or multimodal Pushover becomes not significant.

Keywords: dissipative brace; earthquake engineering; energy dissipation; seismic retrofitting

作者简介：Bergami A.V.，博士，研究员，Email: alessandro.bergami@uniroma3.it。

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