瞭望塔基座大厅混凝土结构设计

Concrete structural design of sightseeing tower base hall

北京瞭望塔由5个单塔组成,各塔身之间利用疏散通道设置4道连接桁架,将5个单塔连接为整体,建筑体型非常复杂。瞭望塔包含基座大厅、塔身、顶部塔冠三部分。底部为混凝土基座大厅,基座大厅屋盖结合建筑采光天窗造型,采用交叉编织混凝土梁板结构,有效保证水平力的传递。基座大厅范围内将上部塔身钢管混凝土筒壳改为钢板组合剪力墙,可以显著增强结构的侧向刚度,有效解决了塔身结构嵌固深度不足的问题。基座大厅入口大厅采用混凝土拱壳,最大跨度近50m,上部最厚覆土12m,边界条件与受力情况复杂,采用加肋方式提高承载力,减轻结构自重。

Beijing sightseeing tower is composed of five single towers.Four connecting trusses are set between the tower bodies by using the evacuation passage to connect the five single towers as a whole.The building shape is very complex.Beijing sightseeing tower consists of three parts:base hall,tower body and top tower crown.A concrete base hall is set at the bottom of the sightseeing tower.Combined with the shape of the building daylighting skylight,the roof of the base hall adopted the cross braid concrete beam-plate structure system to effectively ensure the transmission of horizontal force.Changing the concrete-filled steel tubular shell of the upper tower body into steel plate concret composite shear wall within the base hall can significantly enhance the lateral stiffness of the structure and effectively solve the problem of insufficient embedded depth of the tower body structure.The concrete arch shell is adopted for the entrance of the base hall,with a maximum span of nearly 50m and a maximum thickness of 12m overburden for the upper part.The boundary conditions and stress conditions are complex.The ribbed beam is adopted to improve the bearing capacity and reduce the self weight of the structure.