Numerical analyses of stability and deformation behavior of reinforced and unreinforced tunnel faces

Abstract In traditional tunneling, an analysis of the face stability is required to avoid failure mechanisms or excessive face extrusion. Face reinforcement can improve face stability and reduce deformations. In the present work a numerical study of both unreinforced and reinforced tunnel excavation faces by means of 3D FEM analyses is presented. The results are compared with those of the traditional limit equilibrium method and with an analytical solution based on previous numerical studies. It could be shown that the LEM may lead to non-conservative results. Finally, the deformation response is assessed and the benefits of face reinforcements are investigated.

[1]  Georgios Anagnostou,et al.  Comparing the limit equilibrium method and the numerical stress analysis method of tunnel face stability assessment , 2011 .

[2]  Hideto Mashimo,et al.  CENTRIFUGE MODEL TEST OF TUNNEL FACE REINFORCEMENT BY BOLTING , 2003 .

[3]  Georg Anagnostou,et al.  The dimensioning of tunnel face reinforcement , 2007 .

[4]  Chung-Sik Yoo,et al.  Finite-element analysis of tunnel face reinforced by longitudinal pipes , 2002 .

[5]  Charles Wang Wai Ng,et al.  A three-dimensional parametric study of the use of soil nails for stabilising tunnel faces , 2002 .

[6]  Helmut Schweiger,et al.  Slope stability analysis by means of finite element limit analysis and finite element strength reduction techniques. Part I: Numerical studies considering non-associated plasticity , 2015 .

[7]  Pieter A. Vermeer,et al.  Tunnel Heading Stability in Drained Ground , 2002 .

[8]  Alessandra Paternesi,et al.  Excavation works in stiff jointed clay material: examples from the Trubi formation, southern Italy , 2015, Landslides.

[9]  G. Anagnostou,et al.  Modelling Seepage Flow During Tunnel Excavation , 1995 .

[10]  Helmut Schweiger,et al.  FE-analysis of reinfoced tunnel face , 2004 .

[11]  Daniel Dias,et al.  Stabilisation of the Excavation Face in Shallow Tunnels Using Fibreglass Dowels , 2012, Rock Mechanics and Rock Engineering.

[12]  Helmut Schweiger,et al.  Fe-analysis of reinforced tunnel face , 2004 .

[13]  S. Sloan Geotechnical stability analysis , 2013 .

[14]  Yi Hong,et al.  Numerical parametric study on stability and deformation of tunnel face reinforced with face bolts , 2015 .

[15]  Georg Anagnostou,et al.  Face stability conditions with earth-pressure-balanced shields , 1996 .

[16]  Pierpaolo Oreste Face stabilisation of shallow tunnels using fibreglass dowels , 2009 .

[17]  Pierpaolo Oreste THE STABILITY OF THE EXCAVATION FACE OF SHALLOW CIVIL AND MINING TUNNELS , 2011 .

[18]  Chung-Sik Yoo,et al.  Deformation behaviour of tunnel face reinforced with longitudinal pipes—laboratory and numerical investigation , 2003 .

[19]  Carla L. Zenti,et al.  Technical solutions for soil nails in tunnel face reinforcement and drainage , 2012 .

[20]  Georg Anagnostou,et al.  The face stability of slurry-shield-driven tunnels , 1994 .