斜钢管混凝土柱框架-核心筒-伸臂桁架结构抗震性能研究  

Seismic performance of inclined CFT frame-core tube-outrigger truss structure system

作　　者：成宇 刘界鹏[1,2] 单文臣 李江 CHENG Yu;LIU Jiepeng;SHAN Wenchen;LI Jiang(Key Laboratory of New Technology for Construction of Cities in Mountain Area of the Ministry of Education,Chongqing University,Chongqing 400045,China;School of Civil Engineering,Chongqing University,Chongqing 400045,China;College of Civil and Transportation Engineering,Shenzhen University,Shenzhen 518060,China)

机构地区：[1]重庆大学山地城镇建设与新技术教育部重点实验室,重庆400045 [2]重庆大学土木工程学院,重庆400045 [3]深圳大学土木与交通工程学院,广东深圳518060

出　　处：《建筑结构学报》2023年第6期12-23,共12页Journal of Building Structures

基　　金：国家自然科学基金重大项目(51890902);国家自然科学基金青年项目(52208185)。

摘　　要：为明确钢管混凝土(CFT)柱框架-核心筒-伸臂桁架混合结构的抗震性能,结合典型工程“青岛海天中心”,采用MARC有限元软件对该结构体系进行抗震性能分析。分别进行了多遇地震、设防地震及罕遇地震作用下的弹塑性动力时程分析。结果表明:设置斜CFT框架柱可有效控制结构顶点位移,罕遇地震作用下,最大顶点位移较直CFT框架柱结构的降低约76.6%;斜CFT柱使地震剪力由核心筒向框架转移,转移后的地震剪力更接近双重抗侧力体系的设计要求,即在多遇地震作用下框架部分至少承担结构总底部剪力的20%;同时,结构倾覆力矩的变化与剪力相反。设置斜CFT框架柱的结构可充分利用材料性能,在发挥相同抗侧力作用情况下能取得较好的经济效益。在此基础上,对结构进行基于增量动力分析(IDA)的地震倒塌易损性分析,确定了结构塑性发展路径为连梁、核心筒底部、框架柱底端、伸臂桁架。易损性分析结果表明,CFT框架柱斜置未对结构抗震倒塌安全储备产生不利影响,依然表现出优异的抗地震倒塌能力;结构变截面楼层部分的连梁和周围墙底塑性损伤最为严重,在设计中应对其进行加强。In order to clarify the seismic performance of inclined CFT column frame-core tube-outrigger truss hybrid structures,the seismic performance of this structure system was analyzed using MARC finite element software,with the background of the Qingdao Haitian Center project.Elastic-plastic dynamic time-history analysis under the frequent earthquake,fortification earthquake and rare earthquake was carried out.The results show that the inclined CFT column can effectively suppress the top displacement of the structure by about 76.6%reduction compared with that of straight CFT column frame-core tube-outrigger truss hybrid structures under a rare earthquake.The seismic shear-force transfers from core-tube to frame part due to inclined CFT columns,and the transferred seismic shear-force of the frame part is closer to the seismic design requirement for the dual lateral force resistance system,i.e.,the frame part bears at least 20%of the total base shear-force of the structure under frequent earthquakes.Meanwhile,the change of the structural bottom overturning moment is opposite to that of the seismic shear-force.Subsequently,the seismic collapse fragility analysis of the structure based on incremental dynamic analysis(IDA)was carried out,then the plastic development path of structure was determined as coupling beam,bottom of core tube,bottom end of frame column,and outrigger truss.The fragility results show that the inclined form of CFT frame columns do not adversely affect the safety reserve of the structure and still showed excellent resistance to earthquake collapse.The plastic damage of the coupling beam and the surrounding bottom wall of the variable cross-section floor of the structure is the most serious,and these parts should be strengthened in the design.

关 键 词：超高层建筑 框架-核心筒-伸臂桁架结构 斜钢管混凝土框架柱 增量动力分析 抗震性能 

分 类 号：TU973.1[建筑科学—结构工程] TU311.41