Advance speed-based parametric study of greenfield deformation induced by EPBM tunneling in soft ground

Abstract For earth pressure balance machines advancing through soft ground, it is essential to control the mechanical driving parameters, such as skin friction, face pressure and cutter torque, to minimize the influence on the surrounding environment. A test at a greenfield site was conducted to determine the tunneling-induced soil deformation and the relationship between the mechanical driving parameters and advance speed. A method based on fuzzy statistics was proposed to calculate the standard values and deviations of the advance speed and mechanical driving parameters at the normal state of advancement. A finite element model verified by field measurements was employed to investigate the greenfield response and the effect of the mechanical driving parameters on soil deformation. Further, the response of soil deformation to the mechanical driving parameters was analyzed at the normal state of advancement. The results showed that at the normal state of deep advancement, the skin friction deviation had the greatest influence on the displacement of both the surface and subsurface. Increasing the skin friction increased the settlement above the tunnel and reduced the heave beneath the tunnel. The higher face pressure resulted in smaller settlement near the tunnel crown and heave near the tunnel invert. The larger cutter torque was only able to increase settlement near the tunnel crown. The combined effect of the mechanical driving parameter deviations was dominated by skin friction for the surface settlement. Regarding the subsurface vertical displacement near the tunnel, an offsetting or superimposed effect occurred at various advance stages. The mechanical driving parameter deviations based on a higher advance speed reduced the vertical displacement above the tunnel.

[1]  Ebrahim Farrokh,et al.  Correlation of tunnel convergence with TBM operational parameters and chip size in the Ghomroud tunnel, Iran , 2008 .

[2]  A. Schofield,et al.  Critical State Soil Mechanics , 1968 .

[3]  K. Lee,et al.  The equivalence of a jointed shield-driven tunnel lining to a continuous ring structure , 2001 .

[4]  C. P. Wroth,et al.  Application of the failure state in undrained simple shear to the shaft capacity of driven piles , 1981 .

[5]  Malcolm D. Bolton,et al.  Numerical modelling of group effects on the distribution of dragloads in pile foundations , 2002 .

[6]  J. R. Standing,et al.  Greenfield ground response to EPBM tunnelling in London Clay , 2013 .

[7]  B. Lehane,et al.  Numerical back-analyses of greenfield settlement during tunnel boring , 2013 .

[8]  Kenichi Soga,et al.  Effect of TBM driving parameters on ground surface movements on Channel Tunnel Rail Link Contract 220 , 2005 .

[9]  Lotfi A. Zadeh,et al.  Fuzzy Sets , 1996, Inf. Control..

[10]  Malcolm D. Bolton,et al.  FINITE ELEMENT MODELLING OF EXCAVATION AND ADVANCEMENT PROCESSES OF A SHIELD TUNNELLING MACHINE , 1999 .

[11]  Günther Meschke,et al.  A 3D finite element simulation model for TBM tunnelling in soft ground , 2004 .

[12]  Günther Meschke,et al.  A numerical study of the effect of soil and grout material properties and cover depth in shield tunnelling , 2006 .

[13]  Adam Bezuijen,et al.  Simulating the consolidation of TBM grout at Noordplaspolder , 2009 .

[14]  David Chapman,et al.  Investigating ground movements caused by the construction of multiple tunnels in soft ground using laboratory model tests , 2007 .

[15]  P. Dubois,et al.  ASSESSING A SOFT SOIL TUNNELLING NUMERICAL MODEL USING FIELD DATA , 1999 .

[16]  Jamal Rostami,et al.  3D finite difference model for simulation of double shield TBM tunneling in squeezing grounds , 2014 .

[17]  Jiangfeng Liu,et al.  Analysis of ground movement due to metro station driven with enlarging shield tunnels under building and its parameter sensitivity analysis , 2012 .

[18]  R. Peck Deep excavations and tunnelling in soft ground , 1969 .

[19]  Marco Ramoni,et al.  TBM drives in squeezing ground: Shield-rock interaction , 2008 .

[20]  Numbering Analysis of Ground Settlement by Shield Method Based on the Model of Corrected ‘Equivalent Circle Zone’ , 2014 .

[21]  Shui-Long Shen,et al.  Field performance of underground structures during shield tunnel construction , 2012 .

[22]  Zhang Zhong-miao,et al.  Influences of shield advance rate and abnormal machine halt on tunnelling-induced ground surface settlements , 2012 .

[23]  Huang Tian Numerical Simulation of Excavation Load on Cutterhead in Shield Tunneling Machine , 2011 .

[24]  Harry G. Poulos,et al.  Analytical Prediction for Tunneling-Induced Ground Movements in Clays , 1998 .

[25]  Assaf Klar,et al.  Tunnels in sands: the effect of size, depth and volume loss on greenfield displacements , 2012 .

[26]  Huei-Tsyr Chen,et al.  Tunnel stability and arching effects during tunneling in soft clayey soil , 2006 .

[27]  Günther Meschke,et al.  On the influence of face pressure, grouting pressure and TBM design in soft ground tunnelling , 2006 .

[28]  Zhang Li-ming Field monitoring and analysis of effects of metro tunnels under historic buildings , 2013 .

[29]  Robert J. Mair,et al.  Tunnelling and geotechnics: new horizons , 2008 .

[30]  Gu Chenying STUDY OF ESTABLISHED MECHANISM AND SETTING STANDARD OF CHAMBER EARTH PRESSURE FOR EARTH PRESSURE BALANCE SHIELD , 2012 .

[31]  Yu Zhan-kui,et al.  Study on transverse effective rigidity ratio of shield tunnels , 2006 .

[32]  Kenichi Soga,et al.  Modelling of long-term ground response to tunnelling under St James's Park, London , 2007 .

[33]  D. Potts,et al.  The influence of soil anisotropy and K0 on ground surface movements resulting from tunnel excavation , 2005 .

[34]  Anders Laeskogen Palm Pipe Jacking and TBM tunnelling in soft soil conditions , 2012 .