新建隧道下穿多座隧道施工技术

以渝黔引入贵阳枢纽铁路龙宝冲隧道下穿6座已建及在建隧道工程为例,结合现场,详细分析、介绍了下穿隧道施工方案、原则、施工方法;提出了新建铁路隧道近距离下穿隧道交叉点附近施工爆破控制、防护方案,以及新建、既有隧道的监控量测、超前地质预报、安全性评估与评价等施工技术;解决了下穿隧道施工中既保证新建隧道施工安全,又保证既有隧道不受影响的问题。

Construction Technology for New-built Tunnel Construction Underpassing Existing Tunnels

Based on the engineering example of Longbaochong Tunnel on the connection railway from Chongqing-Guizhou Rail to Guiyang Railway hub under 6 existing railway and railway under construction,combined with the field condition, construction scheme,principle,construction method for the construction underpassing tunnel are analyzed and introduced in detail;blasting control and protection scheme for blasting construction of the new railway tunnel underpassing the existing tunnel with a close distance near the intersection are put forward as well as the new and existing tunnel monitoring measure-ment,advance geological forecast,safety assessment and evaluation of construction technology.The construction underpass-ing tunnel can ensure the safety of the newly-built tunnel and ensure the tunnel is not affected.