基于E-μ模型的约束屈曲支撑结构抗震设计与评估方法  

Seismic Design and Performance Evaluation Method for Buckling Restrained Brace Frame based on E-μ Model

作　　者：徐诗婷 董志骞 李钢[1] XU Shiting;DONG Zhiqian;LI Gang(State Key Laboratory of Costal and Offshore Engineering,Dalian University of Technology,Dalian 116024,China)

机构地区：[1]大连理工大学海岸和近海工程国家重点实验室,辽宁大连116024

出　　处：《防灾减灾工程学报》2021年第6期1238-1247,共10页Journal of Disaster Prevention and Mitigation Engineering

基　　金：辽宁省博士科研启动基金计划项目(2019-BS-052);国家自然科学基金项目(51908105);辽宁省“兴辽英才计划”项目(XLYC1902043)资助。

摘　　要：既有中心支撑钢框架结构采用约束屈曲支撑进行替换加固时,常需进行多次非线性时程分析,以获取约束屈曲支撑的承载力和刚度。为避免大量的非线性分析与迭代计算,通过计算各参数条件下单自由度中心支撑钢框架结构和约束屈曲支撑结构的延性需求谱,建立了在延性需求满足抗震加固要求条件下的约束屈曲支撑结构等效耗能(E)与延性需求(μ)之间的关系,即E—μ模型。基于该模型提出了一种约束屈曲支撑结构抗震加固设计与简化评估方法。最终通过对一个6层中心支撑钢框架结构采用约束屈曲支撑进行加固设计与评估,验证了所提方法的适用性。Multiple nonlinear dynamic history analyses should be performed during seismic and retrofit design of steel concentrically braced frames(CBFs)replaced with buckling restrained braces(BRBs)in order to obtain the strength and stiffness of BRBs. To avoid the iterative nonlinear dynamic analysis,the ductile demand spectra of the single-degree-of-freedom CBFs and the buckling restrained brace frames(BRBFs)with different reserve parameters were firstly calculated;then the relation between equivalent energy(E)and ductility demand(μ)of BRBFs under the condition that the ductility demand meets the requirements of seismic demand,namely E-μ model,was presented. Based on this model,a novel method for seismic reinforcing design and simplified evaluation of the BRBFs was proposed. The method was applied to a 6-story braced-frame structure retrofit project and the result showed that the method proposed in this paper is accurate and applicable in design.

关 键 词：约束屈曲支撑 中心支撑钢框架结构 等效耗能 延性需求 抗震设计 

分 类 号：TU391[建筑科学—结构工程]