单层折面空间网格结构性能研究及设计

Study on structural performance and design of single-layer folded-plane spatial reticulated structure

结合深圳世界大学生运动会体育中心主体育场结构设计的关键问题,剖析单层折面空间网格结构的受力机理,对其刚度与变形控制、动力特性设计、极限状态下受力破坏机理、稳定承载力及强度设计等问题进行了探讨与研究。研究表明:提高径向拟桁架体系的抗弯刚度,如增大立面拟桁架柱中构件的截面积,以及增大屋面折面或立面折面的高跨比是提高结构整体刚度的有效方式;设置肩谷环向构件能够显著减小结构的自振周期,从而减弱风振效应;应重视受力较大的拉弯主构件设计,其与节点的连接部位在施工时应重点控制焊接质量。合理设计下,单层空间折面网格结构具有良好的刚度、稳定承载力性能及变形能力,同时具有足够的安全储备,在关键部件失效的情况下不会发生连续倒塌。

The load-carrying capacity and failure mechanism of single-layer folded-plane spatial reticulated structure,associated with the key design problems of main stadium in Shenzhen Universiade Sport Center are studied.Based on numerical analysis in the stiffness control,dynamic characteristic,failure mechanism,and load-carrying capacity of the structure,the conclusions are drawn,which indicate that the structural stiffness can be increased by one of the following measures,namely amplifying the bending stiffness of radial trusses,enlarging the rise-to-span ratio of folded plate unit in the roof and elevation,and adding circumferential members at the shoulder valley in the structure.It is also proposed that the welding quality of the joints should be controlled carefully to which primary members subjected to both tension and bending are connected,for it has great influence on the load-carrying capacity.With rational and careful structural design,a single-layer folded-plane spatial reticulated structure can have sufficient integral structural stiffness,high load-carrying capacity and good ductility.Meanwhile the overall collapse can be prevented in the case of failure of key members.