微型盾构接收安全关键技术研究

Research on the Key Technology of Receiving Safety of Micro Shield

随着城市化建设进程的不断推进,老城区地下管网建设受制约的边界条件越来越多,管网线路选择时需要规避的既有构筑物多,线性越来越复杂;与此同时为了满足日益递增的功能需求管网口径越来越大,以上原因造成在某些特殊情况下顶管工艺无法满足管网施工需求,该背景下直径3 m以下的微型盾构工艺逐渐成为新的选择。南京市洪武路污水主干管下穿外秦淮河管道受上游既有管道及下游泵站选址影响沿外秦淮河敷设于河床以下,线型总体呈“S”型,最小曲线半径180 m、最小覆土厚度2.6 m,采用盾构法施工,管片内径2.1 m、外径2.6 m。该项目为国内最小断面盾构法隧道,地质情况复杂、边界条件多、施工难度大,在老城区管网建设中具有代表性意义,基于该背景,本文对微型盾构的接收安全相关技术进行研究,旨在为类似工程提供一定参考。

With the development of urbanization,there are more and more restricted boundary conditions for the construction of underground pipe network in the old urban area.There are more and more existing structures to be avoided in the selection of pipe network lines,and the linearity is more and more complex.At the same time,in order to meet the increasing functional requirements,the caliber of pipe is more and more large,which causes that the pipe jacking process cannot meet the pipe network construction in some special cases of this context,the micro shield technology with diameter less than 3m is becoming a new choice.The main sewage pipe of Hongwu Road in Nanjing runs under the outer Qinhuai River and is laid under the riverbed along the outer Qinhuai River due to the influence of the existing upstream pipeline and the site selection of the downstream pump station.The overall line shape is"s"type,with the minimum curve radius of 180m and the minimum cover thickness of 2.6m.The shield method is adopted for construction,with the inner diameter of 2.1m and outer diameter of 2.6m.The project is the domestic minimum cross-section shield tunnel,with complex geological conditions,many boundary conditions and difficult construction,which has representative significance in the construction of old urban pipe network.Based on this background,this paper studies the receiving safety technology of micro shield,aiming to provide some reference for similar projects。