尽管采用耗能支撑简行抗震加固比采用基简隔震 等方法的概念更清晰和简简，但是耗能构件本身以及 加固后简构的简简非简性特性简致采用耗能支撑简行 抗震加固需要更简简的简简简简。迄今简止，有简多 的简简方法被提出来，基于能力简的简简方法[1]是简 些方法里最有简用价简的,其他采用非简性简力分析的 方法由于简于简简而不适合工程简用。事简上，既有 建筑的简多特点（比如简量和简度的不简简，薄弱简 的存在等）会简致采用简定简荷简模式的方法简行 pushover 分析的简简方法的精确度下降。Bergami 和 Nuti[2,3]指出，耗能构件的简简有两个主要目简：增加 简构的耗能能力以及简简化简构的简度和简度分布 （简些可以通简定简一个合适的准简来保简支撑在立 面和平面内得到合理的布置）。本文中的两个工程加 固简例（在意大利普遍存在的中高简建筑）表明，高 简模简不简跟建筑平面不简简有简，而且和建筑简数 有简系。Goel 和Chopra[4]通简在既有建筑上采用多模 简pushover 分析和非简性简力分析，简简采用多模简 pushover 分析代替简模简pushover 分析简行加固简算 是必要的。
The research presented in this paper deals with the seismic retrofitting of existing frame structures by means of passive energy dissipation. An iterative displacement-based procedure, based on capacity spectrum is described and some applications are discussed. The general procedure has 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. In this work the procedure has been applied, with both traditional pushover (load profile proportional to first mode) and multimodal pushover, to an existing r.c. frame building. In the application presented the buckling restrained braces have 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 r.c. frame building (higher than 30 metres) but, once this building is retrofitted, and therefore regularized, with a bracing system, the difference between using monomodal or multimodal pushover becomes not significant.
Bergami, A.V., Liu, X., Nuti, C., Zhou, Z. (2014). Seismic retrofitting of reinforced concrete frame and concentric braced steel buildings with dissipative bracings. In Proceedings of: The 2nd International Conference on Steel and Composite Structures for Large-scale Buildings Shanghai, China, 17-19 April, 2014.
Seismic retrofitting of reinforced concrete frame and concentric braced steel buildings with dissipative bracings
BERGAMI, ALESSANDRO VITTORIO;NUTI, CAMILLO;
2014-01-01
Abstract
The research presented in this paper deals with the seismic retrofitting of existing frame structures by means of passive energy dissipation. An iterative displacement-based procedure, based on capacity spectrum is described and some applications are discussed. The general procedure has 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. In this work the procedure has been applied, with both traditional pushover (load profile proportional to first mode) and multimodal pushover, to an existing r.c. frame building. In the application presented the buckling restrained braces have 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 r.c. frame building (higher than 30 metres) but, once this building is retrofitted, and therefore regularized, with a bracing system, the difference between using monomodal or multimodal pushover becomes not significant.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
