Minería y Geología (Feb 2020)

Optimal geomechanical classification for evaluating the rock mass from coalface Section IV of Levisa-Mayarí tunnel

  • Alexander Ochoa-Quesada,
  • Maday Cartaya-Pires,
  • Jorge Luis Blanco-Blázquez

Journal volume & issue
Vol. 36, no. 1
pp. 50 – 64

Abstract

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The East-West Trasvase engineering work, designed to drive water from Nipe-Sagua-Baracoa mountain range Rivers to the northern Holguín-Camagüey plains, includes building canals, dams and tunnels. During the work on section IV of Levisa-Mayarí tunnel, there were instability problems with the perforated mass. This research was intended to evaluate several geomechanical classifications (Barton-Q, Bulichev-S, Bieniawski-RMR, and Hoek-GSI) for choosing the most appropriate one and adjusting its parameters to the rock mass characteristics. Cracking was evaluated by parked approximately 1.50 m, according to the progress of the tunnel and by lithology. For data processing, Dips v5.0 and Unwedge v3.0 softwares were used; the adjustment of geomechanical parameters was performed by using the trial and error method. There are three cracks families which predominate in the rock mass and its quality is classified from poorly to bad. It is concluded that Hoek and Marinos’ GSI classification with correlation adjustments with the sclerometer and the Barton Q quality index are the ones that best suit the particularities of the rock mass studied, being the latter who best results offer to project support solutions.

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