摘要
目前针对双连拱隧道施工影响的理论分析中较少考虑中导洞带来的施工效应,而含中导洞的双连拱隧道是较为常见的一种设计类型。实际施工中,中导洞先行施工,存在中导洞与左洞1、右洞2共用衬砌边界以及中隔墙的回筑工序。基于复变函数理论解和Schwarz交替法,提出了考虑中导洞施工效应的双连拱隧道衬砌与围岩应力和变形的计算方法。针对中导洞与左右相邻洞室具有共用衬砌边界的特点,利用柯西积分法进行求解时,将各洞衬砌与围岩接触的边界积分条件转化为仅存在单洞时的完整边界积分与共用边界积分之差,与采用Schwarz交替法求解三洞相互作用过程中某一洞室开挖对邻洞产生“附加面力”的过程一致。基于苏州七子山连拱隧道工程,将解析结果与监测数据、数值模拟结果进行对比,证明了复变函数方法的可行性。此外,针对围岩泊松比、围岩弹性模量、中导洞高宽比、连拱整体对称性为关键因素,对围岩位移和衬砌临空面位移开展敏感性分析。结果表明:围岩弹性模量变化对洞1及洞2衬砌位移影响趋势一致。在相同角度下,围岩弹性模量越大,衬砌总位移越小,洞1、洞2衬砌位移均呈现“W”型,位移递增趋势拐点均位于左右拱脚处;中导洞高宽比越大,中导洞截面越趋向“高窄”型,中导洞围岩与衬砌最大主应力均出现增大趋势;当中导洞尺寸不变时,将另一洞室截面尺寸增大及减小,变为对称施工条件时,原洞室衬砌位移也出现增大及减小趋势,且共用衬砌区域增大趋势更明显。
At present,theoretical analyses on double-arch tunnel construction effects have rarely considered the construction impacts induced by the middle guide tunnel,despite its prevalence in practical designs.During construction,the middle guide tunnel is excavated first,sharing its lining boundary with adjacent left(tunnel 1)and right(tunnel 2)caverns,while requiring backfilling and reconstruction of the central diaphragm wall.Based on complex variable function theory and the Schwarz alternating method,this study proposes a calculation approach for stress and deformation in lining-surrounding rock systems of double-arch tunnels incorporating middle guide tunnel effects.For the shared lining boundary between the middle guide tunnel and lateral caverns,the Cauchy integral method transforms boundary integral conditions into the difference between complete single-cavity integrals and shared boundary integrals.This aligns with the Schwarz alternating method’s concept of“additional surface forces”generated during three-cavity interaction analysis.Validation against monitoring data and numerical simulations from the Suzhou Qizi Mountain double-arch tunnel project confirms the feasibility of this complex function approach.Parametric sensitivity analyses were conducted for Poisson’s ratio,surrounding rock elastic modulus,middle guide tunnel aspect ratio,and double-arch symmetry.Key findings include:elastic modulus variations exhibit consistent impacts on Tunnel 1 and 2 lining displacements-higher modulus correlates with reduced total displacement at equivalent angles,showing“W”-shaped profiles with inflection points at arch springings.Increased middle guide tunnel aspect ratio(toward“tall-narrow”geometry)elevates maximum principal stresses in both surrounding rock and lining.Symmetrical enlargement/reduction of adjacent cavern sizes while maintaining middle guide tunnel dimensions amplifies/reduces original cavern lining displacements,particularly in shared lining regions.
作者
张治国
李乃义
牛瑞
王安源
朱正国
ZHANG Zhi-guo;LI Nai-yi;NIU Rui;WANG An-yuan;ZHU Zheng-guo(School of Environment and Architecture,University of Shanghai for Science and Technology,Shanghai 200093,China;China Railway Tunnel Group Co.,Ltd.,Guangzhou,Guangdong 511458,China;The 2nd Engineering Co.,Ltd.of China Railway Tunnel Group,Langfang,Hebei 065000,China;State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures,Shijiazhuang Tiedao University,Shijiazhuang,Hebei 050043,China)
出处
《岩土力学》
北大核心
2025年第S1期141-158,共18页
Rock and Soil Mechanics
基金
国家自然科学基金资助项目(No.52478402)
中铁隧道局二处研究课题
关键词
双连拱隧道
中导洞
SCHWARZ交替法
复变函数
应力场
位移场
continuous arch tunnel
middle guideway
Schwarz alternate method
complex variable function
stress field
displacement field
