南京某文娱中心大跨空间钢结构设计

Design of large⁃span space steel structure of a civic center in Nanjing

南京某文娱中心为造型复杂的大跨空间钢结构体系,由异型屋面、超高排架柱和高大抗风幕墙构成。为满足屋面建筑造型和屋顶排烟等需求,提出了双向变高度的折板网架屋盖结构形式,最大限度降低了二次找坡的用钢量。基于可视化编程平台Grasshopper,通过分区处理的方式实现了屋盖的参数化建模,后导入3D3S进行结构分析和设计,结果表明该屋盖整体刚度较好,满足设计要求。屋盖下方采用25根无侧向支撑的超高排架柱提供支承,针对柱高10~60m的情况,对比了混凝土柱、四肢钢管格构柱、四肢钢管混凝土格构柱在截面、成本和功能等角度的差异,最终确定采用经济性和功能均较好的四肢钢管格构柱。根据不同区域特点,将抗风幕墙分为落地幕墙和吊挂幕墙,探讨了它们与主体结构的连接方式,并针对落地幕墙进行了平面桁架、立体桁架和实腹箱形柱3种幕墙结构方案的比选,最终采用成本最低的平面桁架方案。

A civic center in Nanjing is a large⁃span space steel structure system with complex shape,consisting of special⁃shaped roof,super⁃high shelving columns and tall wind⁃resistant curtain walls.To meet the demand of roof shape and smoke exhaust,the bidirectional variable height folding plate gird roof structure was proposed,and the amount of steel used for secondary slope finding was reduced to the maximum.Based on the visual programming platform Grasshopper,the parametric modeling of the roof was realized by partition processing,and then imported into 3D3S for structural analysis and design.The results show that the roof is in a good stiffness and meets the design requirements.The roof is supported by 25 super⁃high shelving columns without lateral support.In view of the column height of 10~60m,the differences in section,cost and function of concrete column,four⁃legged steel tubular lattice column and four⁃legged concrete tubular lattice column were compared,and the four⁃legged steel tubular lattice column with better economy and function was finally selected.According to the characteristics of different regions,the wind⁃resistant curtain wall is divided into floor curtain wall and hanging curtain wall,and the connection mode between them and the main structure was discussed.For the floor curtain wall,three curtain wall structure schemes,namely plane truss,three⁃dimensional truss and solid abdominal box column were compared.Finally,the plane truss scheme with the least cost was adopted.