联合国地理信息会址配套工程网壳结构设计研究

Research on design of reticulated shell structure of United Nations Geographic Information Conference Site supporting project

联合国地理信息会址配套工程采用长轴67428m、短轴52795m的单层类椭球形非规则网壳,与相邻的幕墙、屋顶楼板等结构相连,网壳结构和邻近结构外形关系复杂。从网壳结构建筑需求及网格划分、风洞试验、结构静力分析、稳定分析等方面对网壳结构进行了分析与设计。给出了网壳中部采用K8型时不同圈扩展下的多方案网格划分方案,比较了网壳特点和受力特性,为建筑师提供了选择的机会,满足了建筑师设计意蕴。网壳结构横跨主体建筑立面及屋顶平面,结构荷载规范给出的体型系数无法真实反映网壳结构受风状态,风荷载取值应按照风洞试验确定。由网壳杆件、幕墙构件、楼面梁设计形成的空间巨型桁架,不仅极大地改善了网壳结构的强度和刚度,而且还解决了屋顶大跨度楼面的设计难题。

The United Nations Geographic Information Conference Site supporting project adopts a single-layer ellipsoidal irregular reticulated shell with a long axis of 67428m and a short axis of 52795m,which is connected with adjacent curtain walls,roof slabs and other structures,and the relationship between reticulated shell structure and adjacent structures is complex.The analysis and design of reticulated shell structures were conducted from the aspects of building requirements,grid division,wind tunnel test,structural static analysis,and stability analysis.When K8 type is used in the center of the reticulated shell,multiple grid division schemes under different circle extensions were given,and the characteristics and force characteristics of reticulated shells were compared,which provided a choice opportunity for architects and satisfied their design implication.The reticulated shell structure spans the main building facade and roof plane.The shape coefficient given in the structural load specifications cannot truly reflect the wind state of the grid shell structure,and the wind load should be determined according to wind tunnel test.The spatial giant truss designed by reticulated shell members,curtain wall components,and floor beams not only greatly improves the strength and stiffness of the reticulated shell structure but also solves the design problem of large-span roof floors.