盾构隧道穿越既有铁路桥梁影响分析  

Analysis of the Impact of Shield Tunnel Crossing Existing Railway Bridges

作　　者：龙葳 LONG Wei(China Railway SIYUAN Survey and Design Group Co.,Ltd,Wuhan 430063)

机构地区：[1]中铁第四勘察设计院集团有限公司隧道院,武汉430063

出　　处：《铁道勘测与设计》2024年第3期62-67,共6页Railway Survey and Design

摘　　要：以台州市市域铁路S2线为背景,对隧道施工过程中的重大风险源-隧道连续下穿既甬台温铁路永宁江特大桥、金台铁路永宁江特大桥的施工过程开展了三维数值模拟。台州市域铁路盾构外径为8.8m,盾构距桥桩的最小距离为10.65m,台州市市域铁路S2线隧道下穿既有桥梁的沉降控制变形要求在1mm以内,对穿越过程中的保护措施及隧道施工提出了较高的要求。数值计算结果表明:(1)在无保护措施的情况下,盾构隧道穿越过程中主要引起桥桩竖向位移。(2)隔离桩的设置对减少盾构穿越对桥梁的影响起到了显著作用。A three-dimensional numerical simulation was conducted on the construction process of a major risk source during tunnel construction,which is the continuous underpass of the Yongning River Extra Large Bridge on the Ningbo Taizhou Wenzhou Railway and the Yongning River Extra Large Bridge on the Jintai Railway,against the backdrop of the Taizhou City Railway S2 Line.The outer diameter of the shield tunnel for Taizhou City Railway is 8.8m,and the minimum distance from the shield to the bridge pile is 10.65m.The settlement control deformation requirement for the S2 line tunnel of Taizhou City Railway passing through the existing bridge is within 1mm,which puts forward high requirements for protective measures and tunnel construction during the crossing process.The numerical calculation results indicate that:(1)In the absence of protective measures,the vertical displacement of bridge piles is mainly caused during the tunneling process of shield tunnels.(2)The setting of isolation piles has played a significant role in reducing the impact of shield tunneling on bridges.

关 键 词：盾构隧道 既有铁路 穿越 沉降控制 

分 类 号：U45[建筑科学—桥梁与隧道工程]