盾构超近距离上跨既有线技术研究

A Study of the Technique for a Shield to Under-Cross an Existing Railway at an Extra-Short Distance

地铁盾构超近距离上跨既有线施工,如何保证盾构正常施工及既有线的结构安全及正常运营,是施工中的关键点。结合沈阳地铁十号线中松区间超近距离上跨既有二号线工程,采取利用临时竖井进行障碍物的清除、通过深孔注浆对既有线两侧的土体进行加固、既有线内部施作临时支顶系统、对既有隧道进行实时监测、盾构施工过程中严格控制掘进参数等措施,确保了既有线的安全,为类似地铁施工提供了借鉴和参考。

hen a subway shield is used to perform the drilling construction over an existing railway at an extra short distance how to ensure the normal operation of the shieldand the structural safety and the normal operation of the existing railway are the key points of the construction. With the Zhongsong Section of the project of Subway Line 10 in Shenyang which under-crosses the existing railway of Line 2 at an extra short distance,as the engineering background,dealt with in the paper are the construction techniques adopted for the project, which include adopting temporary shafts for the removal of obstacles consoli-dating the earth bodies on both sides of the existing railway by means of the deep-hole slip casting,providing temporary internal top-supporting system for the existing railway performing timely monitoring of the existing tunnel, strictly controlling the drilling parameters in the course of the shield drilling and other necessary measures. Because of the adoption of all those meas-uresthe safety of the existing railway is fully ensured. The paper may serve as a useful reference for the construction of other similar subways.