类矩形盾构隧道施工期上浮影响因素分析

Influence Factor Analysis for Upward Floating of Quasi Rectangle Shield Tunnel in Construction Period

以国内首例类矩形地铁盾构工程为背景,采用三维有限元软件ABAQUS建立类矩形隧道三维有限元模型,模拟计算同步注浆参数、千斤顶推力、后配套系统重量等因素对施工期类矩形盾构隧道上浮的影响。研究结果表明:通过增大类矩形隧道顶底注浆压力差、千斤顶水平推力、千斤顶竖直向下分力或后配套系统重量可减小施工期隧道上浮变形,采用初凝时间较短的同步注浆浆液是减小施工期隧道纵向变形最有效的措施。研究成果可为今后国内类矩形盾构施工提供参考。

Abstract：On the basis of the first domestic quasi rectangle railway shield, using 3D simulation finite element analysis software ABAQUS, this study establishes the 3D finite model of quasi rectangle shied tunnel and ana- lyzes the upward floating deformation during construction caused by synchronous grouting parameters, cylinder thrust force, back-up system weight, etc. Results show that improving grouting pressure difference between the roof and bottom of the tunnel, horizontal and downward cylinder thrust force or back-up system weight can re- duce upward floating deformation during construction. Using grout with a short initial setting time is the most ef- ficient way to reduce the longitudinal tunnel deformation. The insights provided from this study may contribute to the improvement of quasi rectangle shield tunnel construction.