浅埋偏压隧道下穿桥梁的施工方案研究  

Study on Construction Scheme for Shallow Eccentric-Compression Tunnel Crossing below the Viaduct

作　　者：李讯[1] 何川[1] 陈菲[1] 

机构地区：[1]西南交通大学地下工程系,成都610031

出　　处：《铁道标准设计》2012年第4期93-98,共6页Railway Standard Design

基　　金：国家973计划项目(2010CB732105);交通部西部交通科技项目(200731800039);国家杰出青年科学基金项目(50925830)

摘　　要：新建隧道出口段近接穿过已建高架桥,为了确保隧道施工期间桥梁的稳定性,对施工过程进行了数值模拟分析,比较了先开挖浅埋侧隧道与先开挖深埋侧隧道2种开挖施工顺序,重点研究了施工过程中地表沉降、桥墩位移、桥梁内力等方面的内容。计算结果表明:隧道上半断面的中导洞和两侧弧导洞开挖对地表沉降和桥墩位移的影响最为直接,为关键施工步;隧道施工对5号墩和6号墩影响较大,隧道施工宜采取先开挖浅埋侧的方案,监控量测中应将5号墩、6号桥墩及之间的梁体作为重点关注对象。The exit passage of a new tunnel was located below an existing viaduct at close range.To ensure the stability of the viaduct during tunnel construction,the numerical simulation of construction process was conducted.The two construction sequences between shallow-buried tunnel and deep-buried tunnel were compared with each other,focusing on the ground-surface settlement,pier displacement,and internal force of the viaduct.The simulation results indicated that the excavations of the middle pilot heading of upper cross-section and pilot heading of both sides have the most direct influences on ground-surface settlement and pier displacement,and are the key process of the construction.In addition,the tunnel construction has significant influence on No.5 and No.6 piers.Furthermore,the sequence of excavating the shallow-tunnel first is the optimal construction scheme,and the beam between No.5 and No.6 piers should be paid more attentions during construction monitoring.

关 键 词：浅埋偏压隧道 施工方案 力学行为 数值模拟 

分 类 号：U455[建筑科学—桥梁与隧道工程]