隧道管幕支护施工地表沉降预测方法研究  

Prediction Method for Surface Settlement in Tunnel Construction with Pipe Curtain Support

作　　者：江勇涛 王明年[1] 张艺腾 于丽[1] 江帆 肖泽荣 JIANG Yongtao;WANG Mingnian;ZHANG Yiteng;YU Li;JIANG Fan;XIAO Zerong(School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031;Fuzhou Municipal Construction Development Co.,Ltd,Fuzhou 350108;FujianFuzhou Planning Design&Research Institute,Fuzhou 350108)

机构地区：[1]西南交通大学土木工程学院,成都610031 [2]福州市市政建设开发有限公司,福州350108 [3]福州市规划设计研究院,福州350108

出　　处：《现代隧道技术》2020年第4期82-90,135,共10页Modern Tunnelling Technology

基　　金：福州市市政建设开发有限公司(榕市建20191061号)。

摘　　要：管幕顶管施工将对地层产生扰动,引起地层变形和地表沉降。目前常通过单管沉降叠加的方式进行群管施工地表沉降计算,未考虑管幕群管间相互作用。文章结合文林山隧道出口段采用螺旋出土套管顶进工艺进行管幕施工实例,基于随机介质理论和Mindlin解建立考虑地层损失和施工应力的单管顶进施工地表沉降计算方法,并引入群管施工地表沉降修正函数建立管幕群管施工地表沉降计算方法;采用提出的计算方法分析单管顶进施工和群管施工引起的地表沉降变化及分布规律,并通过FLAC3D数值模拟进行验证。结果表明:(1)管幕钢管顶进过程中地表先隆起后沉降,前方地表发生隆起,后方地表发生沉降;(2)管幕钢管顶进引起的地表变形由隧道中线向两侧逐渐衰减,影响基本在左右两侧12 m范围内;(3)后续顶进钢管引起的地表隆起小于第1根钢管,地表沉降大于第1根钢管。Pipe jacking construction for pipe curtain will disturb stratum and cause deformation and surface settle⁃ment.At present the surface settlement caused by group pipes is calculated by superposition of single pipe settle⁃ment without consideration of the interaction of group pipes of pipe curtain.Taking the pipe curtain at exit section of Wenlinshan tunnel for example,which is constructed by the technology of mucking with screw conveyor and jacking with casing,a calculation method for the surface settlement of single-pipe jacking construction considering ground loss and construction stress is established based on stochastic medium theory and Mindlin solution,and the modi⁃fied function for the surface settlement of group pipe construction is introduced to set up a calculation method for the surface settlement of group pipe construction;the change and distribution laws of surface settlements caused by sin⁃gle-pipe jacking and group pipe construction are analyzed and verified by the proposed calculation method and FLAC3D numerical simulation respectively.The results show that:(1)during the jacking process of steel pipes,at first the surface heaves in front and then subsides in the rear;(2)the surface deformation caused by steel pipe jacking gradually attenuates from the center line of the tunnel to both sides,with the affected scope within 12 m of the two sides;(3)the surface heaving caused by the subsequent pipe jacking is smaller than that caused by the first steel pipe,and the surface settlement is larger than that caused by the first steel pipe.

关 键 词：隧道 管幕支护 顶管 地层损失 施工应力 地表沉降 计算方法 

分 类 号：U455.4[建筑科学—桥梁与隧道工程]