浅埋暗挖隧道双层管棚力学特征与变形控制技术  

Mechanical Characteristics and Deformation Control Technology of Double-layer Pipe Shed in Shallow Buried Underground Tunnels

作　　者：许黄凯 XU Huangkai(No.6 Engineering(Xiamen)Co.,Ltd.of CCCC Third Harbor Engineering Co.,Ltd.,Xiamen 361006,China)

机构地区：[1]中交三航局第六工程(厦门)有限公司,厦门361006

出　　处：《铁道勘察》2025年第2期168-175,共8页Railway Investigation and Surveying

基　　金：中交三航局第六工程(厦门)有限公司科技研发项目重点课题(2023-08)。

摘　　要：为研究浅埋暗挖法双层管棚的力学特征,以厦门某暗挖隧道为依托,采用三维数值分析方法,研究管棚支护后围岩变形、围岩压力、管棚沉降及受力特征,并与解析方法进行对比分析,提出控制管棚挠度的施工措施。结果表明,解析方法难以准确考虑围岩荷载的应力相关性和材料非线性影响,从而导致获取的弹性地基梁荷载与反力与实际工程不符;数值分析法获得的管棚沉降曲线形态与解析法基本一致,破坏面与解析法假定的“45°+φ/2”也基本吻合;隧道开挖过程中,掌子面前方上覆围岩荷载有所降低,地基反力的总应力降低,但有效应力增大;为控制管棚挠度,应确保套拱的强度及刚度,控制导向钢管的角度,以及注浆的饱满度。实测表明,隧道开挖后地表沉降仅为2 mm,说明管棚加固对控制地表变形效果显著。In order to study the mechanical characteristics of double-layer pipe sheds using shallow buried excavation method,this paper took a certain underground tunnel in Xiamen as the basis and used threedimensional numerical analysis method to study the deformation,pressure,settlement and stress characteristics of the surrounding rock after pipe shed support.The analysis results were compared and analyzed with analytical methods,and construction measures to control the deflection of the pipe shed were proposed.The results indicate that,the analytical method cannot accurately consider the stress correlation of surrounding rock loads and the nonlinear effects of materials,resulting in difficulty in obtaining values that are consistent with actual engineering for the load and reaction of elastic foundation beams.The shape of the settlement curve of the pipe shed obtained from numerical analysis is basically consistent with the analytical method,and the failure surface of the palm face is also basically consistent with the assumed“45°+φ/2”in the analytical method.During the tunnel excavation process,the load on the overlying rock in front of the tunnel owner decreases,and the total stress of the foundation reaction decreases,but the effective stress increases.To control the deflection of the pipe shed,ensure the strength and stiffness of the arch,control the angle of the guiding steel pipe,and ensure the fullness of the grouting.Actual measurements have shown that the surface settlement after tunnel excavation is only 2 mm,indicating that the reinforcement of the pipe shed has a significant effect on controlling surface deformation.

关 键 词：隧道工程 浅埋暗挖法 双层管棚 超前支护 力学特征 数值分析 

分 类 号：U455.7[建筑科学—桥梁与隧道工程] U456.2[交通运输工程—道路与铁道工程]