拱桥K撑和主梁一体化运架系统设计及应用

Design of All-in-One Delivering and Erection System for Lateral Bracings Between Arch Ribs and Steel Beams in Deck System of Arch Bridge and Engineering Application

为指导转体施工或其它非扣索悬臂法施工拱桥的K撑和桥面主梁安装,依托重庆城开高速蓼子特大桥(主跨252 m中承式钢箱推力拱桥),设计一种以拱肋为承重基础、可大吨位(200 t)起吊、负载行走的拱上一体化运架系统。该系统包括行走子系统、起吊子系统、承重子系统和同步控制子系统。通过数值仿真分析,评估该系统在全拱肋范围内的抗倾覆稳定性,计算结果表明:在最不利拱脚位置(最大倾斜角度40°),该系统虽然出现竖向受力不均匀的现象,但未发生明显的倾斜,不会发生倾覆。蓼子特大桥采用该系统仅用25 d就完成了全桥4道K撑以及19片桥面主梁(含合龙段)的全部安装工作,施工效率较高。

Based on the construction of the Liaozi Bridge of Chengkou-Kaizhou Highway in Chongqing,which is a half-through steel box girder thrust arch bridge with a main span of 252 m,an all-in-one delivering and erection system that can carry heavy components(200 t)while walking on the arch is developed.The system is applicable to erect the k-shaped lateral bracings between arch ribs and steel girders in deck system of the arch bridge that is constructed by rotation method or the arch bridge that could not be constructed by the cable-stayed cantilever assembly/casting method.The all-in-one system consists of a walking subsystem,a hoisting subsystem,a load-carrying subsystem and a synchronous control subsystem.The possible overturning of the all-in-one delivering and erection system at any location of the arch was numerically simulated.It is shown that at the most unfavorable location of arch springing(with a maximum inclination angle of 40°),the all-in-one delivering and erection system was subjected to uneven vertical forces,but did not notably incline,or consequently overturned.In the Liaozi Bridge,it took only 25 days to complete the erection of the four K-shaped lateral bracings and 19 steel girders(including the closure segment)in the deck system,reaching the expected construction efficiency.