3D Simulation of Mechanised Excavation in Brittle Rock

Abstract:

During the excavation by TBM of the Aicha Exploratory Tunnel along the Brenner Base Tunnel in Italy, in hard brittle granitic rocks, an instability phenomenon occurred at chainage 6+151. The left-hand sidewall lining partially collapsed for a length of approximately 60m. This led to a stoppage of the TBM lasting about 4 months. With the reconstruction of the geological model, a sub-vertical fault, not forecast at the design stage, was identified parallel to the direction of the excavation. In this paper, a three-dimensional (3D) model, which simulates the complex interaction between the rock mass, the TBM and its system components, and the tunnel support, is presented. The model accounts for the main machine components: shields, cutterhead, grippers, pea gravel and lining. The brittle failure of a thin granite diaphragm between the fault zone and the tunnel wall is reproduced and the results are discussed in terms of failure zone and horizontal displacements.

• Periodical: Applied Mechanics and Materials (Volumes 353-356)
• Pages: 1724-1731
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.353-356.1724
• Online since: August 2013
• Authors: Kai Zhao*, Michele Janutolo, Guo Xing Chen
• Keywords: 3D Simulator, Brittle Rock, Double Shield Universal (DSU) TBM, Fault Zone, Mechanised Excavation

References

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DOI: 10.1007/s00603-012-0224-3