大跨度重型钢桁架桥梁卸载施工技术

Unloading Construction Technology of Large-span Heavy Steel Truss Bridge

结合青岛某大跨度重型天桥工程,通过试验研究,根据大跨度重型钢桁架桥梁分段吊装特点,对螺旋千斤顶卸载进行优化,提出千斤顶+气割法卸载。卸载前使用千斤顶支承于卸载点处,然后用气割切割工字钢垫梁腹板使其缓慢受热变形至千斤顶位置,经多次回程+气割循环完成卸载。

Combined with a large-span heavy flyover project in Qingdao, through experimental research, according to the segmental lifting characteristics of the large-span heavy steel truss bridge, the unloading of the screw jack is optimized, and the unloading of the jack + gas cutting method is proposed. Before unloading, a jack to support at the unloading point is used, and then gas cutting is used to cut the web of the I-beam cushion beam to slowly heat and deform it to the jack position, and the unloading after multiple return strokes + gas cutting cycles is completed.