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3D Numerical Analysis Of A Shallow Tunnel Face Reinforced By Longitudinal Pipes

دراسة عددية ثلاثية الأبعاد لجبهة حفر نفق سطحي مدعمة بالأنابيب الطولية

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 Publication date 2018
and research's language is العربية
 Created by Shamra Editor




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Supporting tunnel face by Fiber glass pipes technology is an effective method to maintain the stability of tunnel face, thus reducing surface settlements, face deformation and maintaining the safety of the workers and the mechanisms used in tunneling. This paper presents the results of finite-difference numerical analyses (FLAC3D program) on the behavior of a shallow tunnel face reinforced by longitudinal fiber glass pipes. A 3D numerical model has been calibrated and used to demonstrate the effectiveness of this technique, and perform a parametric study to determine the critical reinforcements parameters (the density (number of pipes)(A) and length (L)). The results indicate that the face reinforcement technique using longitudinal fiber glass pipes can significantly reduce the movements (face displacement and surface settlements), and thus improving the face stability. These movements decrease by increasing the length of the pipes and increasing the density of the pipes until reaching the critical density, and when we reach the critical length, the pipes must be renewed to maintain the stability of the tunneling process.



References used
Atkinson,J.H., Potts,D.M. Subsidence above shallow tunnels in soft ground. Jnl. Geotech. Eng. Div., ASCE, GT4,PP. (1977), 307-325
LUNARDI, P. The influence of the rigidity of the advance core on the safety of tunnel excavation. Gallerie e grandi opere sotterranee, 52, (1997)
GALLI,G; G RIMALDI, A; LEONARDI, A .Three-dimensional modeling of tunnel excavation and lining . Computers and Geotechnics 31 (2004)
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