南昌绿地主塔楼塔冠结构分析与设计方法研究

Analysis and Design Method Research of Nanchang Greenland Main Tower Crown Structure

南昌绿地塔冠建筑造型复杂;塔冠结构高度53 m,且位于250 m标高的主塔楼结构大屋面之上,为整个项目设计的难点之一。介绍了塔冠的结构体系,以及为满足复杂建筑造型结构构件布置策略。论述了塔冠关键荷载的取值方法。针对塔冠空中位置高、建筑造型特殊、构件关系复杂等特点开展了一系列的专项分析与研究。研究了塔冠鞭梢效应,获得了塔冠独立模型分析时由于鞭梢效应产生的地震作用放大系数;开展了塔冠关键柱屈曲分析,通过弹性屈曲理论获得复杂连接关系下关键柱的计算长度系数,进行构件设计;论述了塔冠关键外框节点ANSYS有限元分析方法及分析结果,关键节点在控制荷载组合下仍处于弹性工作状态。最后,陈述了塔冠独立模型的计算结果:塔冠的总体指标以及构件验算均满足规范要求。本工程塔冠的分析与设计策略将能够对相关工程提供有益的参考。

Architectural shape of Nanchang Greenland main tower crown is quite complex;In addition, the height of the crown is 53 m, which locates above the main tower structure whose height is 250 m. The design of the crown structure is critical to the whole project which is complicated and difficult. Structural system of the crown structure and the structural member layout strategy for satisfying the architectural shape is proposed. Critical load value of the crown structure is discussed. Then, several specialized analyses and research are presented to tackle problems due tohigh location, special building shape and complicated relationship among members of the crown structure. Whiplash effect is evaluated, seismic force magnification factors due to the whiplash effect is calculated. Buckling analysisof the key columns isconducted, the effective length factors of these columns are obtained through elastic buckling theory. The key outer frame connection is analyzed using ANSYS software, and the stress state of the connection is still elastic under the critical loading case. Finally, based on these analyses, the design result of the crown is provided, and the overall indicator and structural member design result both satisfy the code requirements. The analysis and design strategy of the crown structure can provide benefit reference forsimilar projects.