大跨度椭圆形索承单层网壳受力性能及影响因素分析

Analysis on mechanical properties of long-span ellipsoidal cable-supported dome

以常州体育馆屋盖120 m×80 m椭圆形索承单层网壳为背景,研究了椭圆形索承单层网壳结构布置的变化规律,发现采用较大的网格可减小整体结构的用钢量;更密的索杆布置,可显著提高结构的稳定性能;上部区域撑杆高度的增加,能提高结构的刚度与稳定性;下部区域撑杆高度的增加,能减小支座反力及杆件内力。同时探讨了影响椭圆形索承单层网壳受力性能及稳定性能的多个关键因素,通过对椭圆长短轴比值的研究,建议不宜采用长短轴比值过大的平面;通过对索预应力值的研究,提出应以长、短轴支座水平反力均较小作为确定索预应力值的原则;通过对屈曲部位的分析,提出可以通过调整杆件截面,将屈曲部位控制在预定区域,从而用较少的材料取得较大的稳定承载力。

Based on the 120 m × 80 m cable supported dome of the Changzhou Gymnasium,through the research on structural arrangement of the cable-supported dome,it is found that bigger grid size can lead to fewer material usage,higher density of cable-strut system can bring higher stability and longer upper strut can improve the stiffness and stability. Key factors that influence the mechanical properties and stability of a long-span ellipsoidal cable-supported dome were also researched. Through research on long-short axis ratio,a moderate long-short axis ratio for ellipsoidal dome is suggested; through research on cable prestressing procedure,principles to determine the cable prestress forces are suggested; through buckling research,it is suggested that improve a dome's stability by controlling its buckling zone at certain area with adjusting of members.