轨 道 梁 初 始 几 何 缺 陷 对 活 动 屋 盖 运 行 的 影 响

A simplified method is proposed to simulate the complete closure process of the movable roof in a finite element transient analysis. The purpose is to investigate the impact of initial geometric imperfections in the track beam on the safety of the structure and the risk of track jamming of the trolley. This method examines the displacement and stress variation characteristics of the track beam during the closure of the movable roof，and also explores the influence of different types（initial geometric imperfections in z and y directions）and sizes of track beam imperfections on the operation of the movable roof. The results reveal that there is a displacement difference greater than 3.8 mm in the ydirection between the trolley and the track beam during the closure process，and this difference increases as the closure progresses towards the mid-span position. The stress ratio peak value of the track beam is consistent and remains below 0.54，irrespective of the imperfection type and size. The initial geometric imperfections in the z direction have almost no effect on the track beam displacement. Conversely，the initial geometric imperfections in the y direction result in additional displacement in the same direction as the imperfection，and the magnitude of this additional displacement increases with the imperfection size. When the size of the initial geometric imperfection in the y direction is L/250，the maximum lateral displacement ratio of the trolley is 4.3 times higher than that of the ideal model.