新建隧道穿越既有桥梁桩基时的主动预支护技术

随着我国城市化进程的加快,新建隧道穿越既有桥梁桩基的工程越来越多.介绍一种具有防御性的主动预支护技术,在新建隧道穿越既有桥梁桩基时,对采取一般技术手段无有效控制把握,有可预见的大变形,地质条件复杂或重要性桥梁等情况时,可以采取"先加固,后开挖"的施工顺序以及"支顶为主,注浆为辅"的桥梁保护方案,控制桥梁上部结构的变形,以保证桥梁在隧道开挖过程中的正常使用.

An Active and Preprotected Technology of Newly-Constructed Tunnels Going through the Existing Bridge Foundation

With the accelerated process of urbanization in our country,there are more and more projects which newly-constructed tunnels going through the existing bridge pile.This article aims to introduce an active and preprotected technology to control the bridge deformation when the tunnels are adjacent to or under passing the existing bridge pile.When taking the general technical means has no effective control or foreseeable deformation with complex geological conditions,and the bridge is important and so on,the construction sequence of ＂the first reinforcement after excavation＂ and the protection program of the bridge of ＂the synchronous lift is main and grouting reinforcement is auxiliary＂ are used to control the deformation of the bridge superstructure and to ensure the normal use of the bridge during tunnel excavation.