南太湖湿地奥体公园体育场屋盖钢结构设计

南太湖湿地奥体公园体育场外形如同百合花,采用叠合开口双层网壳结构体系,由高低两个屋面叠合而成。屋盖钢结构与下部钢筋混凝土看台部分完全脱开,全都支承在标高6.500m的观众室外平台上。在屋盖悬挑端设置观光走廊。由于屋盖钢结构中间开椭圆形洞口,周边六个入口部分同样对屋盖有削弱作用,所以高低屋面各自单独受力时无法满足承载要求,必须通过高低屋面之间的腹杆将之连接成一个整体受力。分别介绍了内力分析、特征值屈曲分析、几何非线性分析、几何材料双重非线性分析、以及典型相贯节点有限元分析的结果,考虑了半跨活荷载的不利影响。分析表明,该屋盖钢结构具有较好的整体稳定性;对于初始缺陷不敏感;当网壳的最大竖向位移超过1m后,较多杆件进入屈服状态,需要通过双重非线性分析才能获得接近实际的稳定承载力。

Structural design on steel roof of the stadium in Nantai Lake Olympic Wetland Park

The stadium in Nantai Lake Olympic Wetland Park which looks like a lily,adopts the structure system of two-layer shell with openings that composed by the high and low roof.The whole steel roof separates from the lower reinforced concrete stand part,and supports on the outside audience platform with the elevation 6.500m.Especially there is a ring tourist corridor on the cantilever end of the roof.The structural behavior of this system is analyzed.It is hard to satisfy the bearing capacity for the only high or low steel roof,just because the elliptical openings is set in the center and six entrances.Therefore the web members between the high and low roof are very important to form an overall structure.From the results of inner-force analysis,eigenvalue buckling analysis,geometric or material nonlinear analysis,considering the adverse effects of a half-cross live load,it shows that the stability behavior is very good for the steel roof which is not sensitive to the initial imperfections.The typical welded joints were analyzed by the finite element method.After the maximum vertical displacement exceeds 1m,many members yield,so the geometric and material nonlinear analysis must be adopted to approach that of real stability state and capacity of the structure.