高原山区大跨度铁路拱桥施工关键技术  

Key Construction Techniques for Long-Span Railway Arch Bridge in Mountainous Region of Plateau

作　　者：王睿 WANG Rui(Sichuan-Tibet Railway Co., Ltd., Chengdu 610045, China)

机构地区：[1]川藏铁路有限公司,四川成都610045

出　　处：《桥梁建设》2020年第1期105-110,共6页Bridge Construction

摘　　要：高原山区地质条件复杂、气候恶劣、交通不便,大跨度铁路拱桥施工效率低、安全风险高,需对其施工关键技术进行研究。结合我国西部山区部分已建及在建大跨度铁路拱桥施工实例,研究该类桥梁的主要施工技术。结果表明:拱座基础开挖前应进行边坡防护,扩大基础采用明挖法施工,整体嵌固式基础、斜(竖)撑基础采用隧道式开挖方法施工,按大体积混凝土施工拱座混凝土;大跨度拱桥一般采用斜拉扣挂悬臂法施工,拱圈采用缆索吊机吊装,缆索吊机的跨度及吊重能力需经综合比选确定,扣、缆塔可选择合建或分离设置方案;钢结构拱上立柱及上部结构采用缆索吊机安装,混凝土梁采用挂篮悬浇或支架法施工。利用BIM技术进行施工阶段精细化建模,以提高智能化施工。The complex geological condition,harsh weather and poor transport facilities in the mountainous region of plateau make the construction of long-span railway arch bridge face great challenges,especially the issues of low construction efficiency and high security risk.Therefore,it is necessary to select proper construction techniques.Based on the engineering examples of the long-span railway arch bridge both in service and under construction in the west mountainous region of China,the key construction techniques for the bridges of such type was studied.The results show that the mountain slopes should be strengthened before the excavation of the arch seat foundation,the spread foundation should be excavated by open-cut method,and the integral embedded foundation and inclined(vertical)support foundation should be constructed in the tunneled excavation manner.The concrete of the arch seat can be cast in accordance with the standards of mass concrete.At large,the long-span arch bridge is constructed by the cantilever method using a fastening stay system.The sections of arch ring are hoisted by cable cranes,and the stretch length and lifting capacity of the cable crane need to be determined via comparison.The lifting and fastening towers can be the same towers or individually built for specific functions.The steel spandrels and superstructure can be constructed by cable cranes and the concrete beams are cast using form travelers or on scaffoldings.BIM technology can be exploited to build the refined models of the structure during construction process,so as to make the construction more intelligent.

关 键 词：铁路桥 高原山区 大跨度拱桥 拱座基础 拱圈 缆索吊机 斜拉扣挂法 施工技术 

分 类 号：U448.22[建筑科学—桥梁与隧道工程] U445.4[交通运输工程—道路与铁道工程]