PLANE STRAIN ANALYSIS IN MODELLING THREE-DIMENSIONAL TUNNEL EXCAVATIONS

This technical paper aims to clarify the relations between the results predicted by plane strain modelling and the solutions given by 3-d analysis, for a circular tunnel driven in a homogeneous, isotropic, elasto-viscoplastic medium. It presents the results of a nonlinear axisymmetric finite element simulation of tunnelling in a rock mass, which investigates the stress and displacements behind an advancing tunnel face. All the results obtained from the 3-d modelling have been compared with the related 2-d model of similar mesh and material properties. The computational results disprove the widespread assumption that 2-D numerical analysis overpredicts tunnel convergence; such analysis can lead to a significant underestimation error, when a 2-d modelling of a tunnel excavation is used, especially in the prediction of ultimate unlined tunnel convergence. The authors suggest a simple approach for approximating the difference between the 2-d predictions and the more accurate 3-d predictions, although its function and parameters need to be investigated further; corrections of this sort can be obtained by understanding the mechanism of stress redistribution and the influence of the excavation sequence in three dimensions

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/01489062
• Authors:
  • Pan, X D
  • HUDSON, J A
• Publication Date: 1988

Language

• English

Media Info

• Pagination: p. 331-7
• Serial:
  • INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING & GEOMECHANICS ABSTRACTS
  • Volume: 25
  • Issue Number: 5
  • ISSN: 0148-9062

Subject/Index Terms

• TRT Terms: Deformation; Dislocation (Geology); Errors; Excavation; Excavations; Mathematical models; Rocks; Simulation; Structural analysis; Tunnels
• ITRD Terms: 5595: Deformation; 6440: Error; 5155: Excavation (process); 6473: Mathematical model; 5483: Movement; 4154: Rock; 9103: Simulation; 5573: Stress analysis; 3374: Tunnel
• Subject Areas: Bridges and other structures; Geotechnology;

Filing Info

• Accession Number: 00487480
• Record Type: Publication
• Source Agency: Transport and Road Research Laboratory (TRRL)
• Files: ITRD, TRIS
• Created Date: Sep 30 1989 12:00AM