带弱连梁且核心筒单侧收进的超高层结构设计

Design of super high-rise structure with weak coupling beam and core tube retracted on one side

南昌联发中心3#超高层塔楼采用现浇钢筋混凝土框架-核心筒结构体系,核心筒在高区单侧收进。为满足室内净空的设计要求,框架梁采用宽扁梁,核心筒墙肢采用跨高比较大的弱连梁连接。弱连梁削弱了核心筒整体稳定性,尤其在罕遇地震下承载力和延性较差,弱连梁较早破坏并丧失耗能性能。核心筒单侧收进造成结构刚心和质心偏离、结构扭转、楼层刚度突变、承载力突变。通过比选不同钢骨混凝土连梁布置方案,得到耗能性能最优的连梁布置方案,从而优化了结构整体受力性能。分析结果表明:在关键楼层的关键位置布置钢骨混凝土连梁可以解决弱连梁带来的一系列问题,各项指标满足设计要求,也满足室内净空的设计要求。

3#super high-rise tower of Nanchang Lianfa Center adopts cast-in-place reinforced concrete frame-core tube structure system,the core tube is retracted on one side of the high area.In order to meet the design requirements of indoor clearance,the frame beam is wide flat beam,and the core tube wall limb is connected by weak coupling beam with large span height ratio.Weak coupling beams weaken the overall stability of the core tube,especially under rare earthquakes,the bearing capacity and ductility are poor,and weak coupling beams fail earlier and lose energy dissipation performance.The core tube retracted on one side causes the deviation of the structural stiffness center and the mass center,the structural torsion,the sudden change of the floor stiffness,and the sudden change of the bearing capacity.By comparing and selecting different steel reinforced concrete coupling beam layout schemes,the coupling beam layout scheme with the best energy dissipation performance was obtained,so as to optimize the overall mechanical performance of the structure.The analysis results show that the arrangement of steel reinforced concrete coupling beams at key positions of key floors can solve a series of problems caused by weak coupling beams,and all indicators meet the design requirements,as well as the design requirements of indoor clearance.