山区大跨度提篮式钢桁拱桥施工关键技术实践

Study and Practice of Key Construction Technology for the Large-span Basket-type Steel Truss Arched Bridge in Mountainous Area

我国西部山区地质、地形条件复杂,山高坡陡,地势险峻,场地狭小,大跨度拱桥施工难度高、安全风险大.根据贵州林织铁路纳界河大桥的施工实践,系统论述了大跨度提篮式钢桁拱桥的施工技术,总结了从拱脚段精确定位预埋、缆索吊装系统设计、拱肋斜拉扣挂悬臂拼装以及无应力合龙等方面的施工技术特点和控制措施,解决了施工过程中的关键技术难题,可为同类桥梁施工提供参考.

The mountainous areas in Western China features complex geological and topographical conditions.The high mountains with steep slopes and narrow construction space bring great challenges and high risks to the building of long-span arch bridges.Based on the construction practice of the Najiehe Bridge on the Lindai-Zhijin Railway in Guizhou,this paper systematically discusses the construction technology of the large-span basket-type steel truss arched bridge,and summarizes the technical characteristics and control measures in construction including the precise positioning and pre-burying of the skew-backs,the design of the cable hoisting system,the arch rib cable-stayed cantilever assembly erection and non-stress closure etc.This study solves the key technical problems in the construction process and can provide reference for similar bridge constructions.