黄土隧道大挖方段明洞拱墙衬砌快速施工技术研究

为减少边坡防护工程量,消除运营安全隐患,高速铁路高挖方路堑段多以隧道代替路基,即以隧道明洞的方式通过。传统的明洞拼装模板施工时间长、耗损多、且混凝土外观质量无法保证,进而影响防水施工。本文以银西高速铁路宁县一号隧道出口段175 m明洞施工为例,采用多作业面平行施工技术,利用钢筋绑扎台车,配合衬砌台车和外侧整体钢模板连续施工的方法,通过加强对模板拼装、衬砌浇筑及回填等关键工序的过程控制,在确保安全质量的前提下,实现明洞拱墙衬砌快速高效施工的目的。

Research on Rapid Construction Technology for Arch Wall Lining in Open-cut Hole of Large-section Loess Tunnel

In order to reduce the amount of slope protection works and eliminate the hidden danger to operation safety,tunnel is used to replace the roadbed in the high-slope excavation section of high-speed railway,that is,to pass through the open-cut tunnel.The traditional open-cut tunnel needs a long time to assemble formwork,leading to a mount of wastage,moreover,the quality of concrete appearance cannot be guaranteed,thus affecting the waterproof construction.With the example of the 175 m open-cut tunnel construction at the exit section of Ningxian No.1 Tunnel in Yinchuan-Xi’an Highspeed Railway,the article proposed the parallel construction technology of multiple working faces.The steel bar binding trolley cooperated with the lining trolley and external integral steel formwork to continuously control the key processes of formwork assembly,lining concrete pouring,backfilling and so on,the rapid and efficient construction was realized for the arch wall lining of the open-cut tunnel under the premise of ensuring safety and quality.