摘要
通过某388m带加强层的边筒—周边框架体系超高层结构工程设计实例,讨论了耗能伸臂桁架在高层与超高层建筑中的应用及其优越性。采用屈曲约束支撑(BRB)代替普通钢支撑作为伸臂桁架斜腹杆形成耗能伸臂桁架不仅能增加结构的侧向刚度,在罕遇地震作用下还能显著提高结构的整体耗能和延性变形能力,限制伸臂桁架传力路径中桁架杆件传递至框架柱和剪力墙的轴力,起到结构保险丝的作用。本文提出基于能力保护设计法的传力路径子模型和扩展模型分析与设计方法,用于分析伸臂桁架弦杆、各连接节点、剪力墙内嵌钢骨以及传力路径上其他构件和节点的受力,确保在罕遇地震作用下屈服耗能仅发生于屈曲约束支撑(BRB)。提供了本文建议的方法在该超高层建筑结构设计中成功应用的分析与设计实例。同时考虑临时施工工况和永久使用工况,设计了伸臂桁架各连接节点。本文提出的设计方法与实例可供类似工程设计参考。
Using the structural design of a 388 m super tall building with a lateral force-resisting system comprising a side core-perimeter moment frame and outrigger and belt trusses as an example,this paper discusses the application and advantages of energy dissipating outrigger trusses in tall and super tall buildings.Buckling-Restrained Braces(BRBs)are employed as diagonal members of outrigger trusses instead of conventional steel concentric diagonal members to form energy dissipating outrigger trusses which not only enhance lateral stiffness but also substantially increase energy dissipation and ductile deformation capacities when subjected to Maximum Considered Earthquake shaking.In addition,energy dissipating outrigger trusses limit the axial forces transferred to perimeter columns and shear walls through the load paths of outrigger truss member force transfer when subjected to Maximum Considered Earthquake shaking,acting as structural fuses.Based on the capacity design principle,this paper proposes the substructure and the assembly load path methods for analysing and designing the chord members and connections of the trusses,the steel members embedded inside the shear walls,as well as the outrigger truss to shear wall and the outrigger truss to perimeter column connections along the load paths.The proposed methods ensure that yielding and energy dissipation occur in the Buckling-Restrained Braces(BRBs)only.Detailed modelling and analysis procedures and results are provided to illustrate the successful application of the proposed methods to the example super tall building.The connections of the outrigger trusses are designed considering both the temporary and the permanent design situations.Recommendations made in this paper may serve as a valuable reference for structural design of tall and super tall buildings.
作者
侯悦琪
刘洺辰
段小廿
PARKINSON Adrian
HOU Yueqi;LIU Mingchen;DUAN Xiaonian;PARKINSON Adrian(Structural Engineering Group,Foster+Partners,London SW114AN,England)
出处
《建筑结构》
CSCD
北大核心
2022年第S01期994-1001,共8页
Building Structure
关键词
超高层建筑
屈曲约束支撑
耗能伸臂桁架
传力路径
能力保护设计
连接节点设计
super tall buildings
buckling-restrained brace
energy dissipating outrigger truss
load path
capacity design
connection design
