山区高速公路桥隧相连地段梁体预制、架设施工技术

Construction Techniques for Precasting and Erection of Girders at Connection Section of Expressway Bridge and Tunnel in Mountainous Region

为解决山区高速公路桥隧相连地段梁体预制、架设难题,以济晋高速公路工程中桥隧相连地段梁体施工为例,介绍该工程中四里沟大桥和四里沟中桥的梁体预制及架设技术。通过梁体预制及架设方案比较,采用在隧道内预制梁方案,解决了隧道口无场地的问题;采用满堂支架配合人字扒杆架梁方案,并通过合理利用现场地形和资源(隧道弃碴),解决了架桥机无法在隧道口架梁的问题。该梁体预制、架梁施工技术适用于梁片数量少、梁体吨位大,隧道口距桥台尾距离小于10m,且采用架桥机架梁既困难成本又很高的桥隧相连地段。

To tackle the problem of precasting and erection of girders at the connection section of expressway bridge and tunnel in the mountainous region,the construction of the girders at the connection sections of bridges and tunnels of Jiyuan-Jincheng Expressway Project was cited as an example and the construction techniques for precasting and erection of the girders of the Sili Gully Bridge and the Sili Gully Middle Bridge of the project were presented.Through comparison of the precasting and erection schemes,it was determined that the girders thereof would be precast inside the tunnels and the problem that there were no construction sites at the openings of the tunnels was solved.With the utilization of the staging aided by the standing derricks and the rational utilization of the site topography and resource（the abandoned broken stones from the tunnels）,the problem that the overhead launching gantry could not be used for erection of the girders at the openings of the tunnels was solved.The construction techniques herewith are applicable to the connection section of bridge and tunnel when a small number and large tonnage of girders are precast and erected,the distance from the back of abutment to the opening of the tunnel is less than 10 m and the utilization of the overhead launching gantry is difficult and is costly.