央视新台址主楼悬臂钢结构安装技术

Installation Technology of Cantilever Steel Structure in Main Building of CCTV New Station

央视新台址主楼悬臂结构具有悬挑跨度大、重量大、结构双向倾斜高空折形对接、多接头异形构件多、安装风险大等施工特点,使得施工中结构稳定性、安全性、精度控制、结构反变形预调处理和变形控制困难。指出了施工中需要考虑的问题,并采用两塔悬臂分离安装、逐步阶梯延伸、空中阶段合拢的安装方法,介绍了安装流程和安装工艺,并采用计算机全过程模拟来保证安装步骤、分区分跨、阶梯延伸、阶段合拢的可行性和安全性。

There were some construction characteristics in cantilever steel structure of CCTV New Station main building, such as large-span, heavy weight, bidirectional inclining steel columns, folded joints at high altitude, large number of special shaped components with multiple joints and large installation risk, etc. It was difficult to control structure stability, safety, precision, anti-deformation preset and deformation in construction. Based on attention points, construction method was introduced, that was two cantilever towers being installed separately and extended ladder by ladder, then two cantilever parts were closured at high altitude. At the same time, the whole construction process was simulated by computer to guarantee feasibility and safety of installation steps, areas and spans, extending ladders and closure.