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Effect of pillar reinforcement on long-term stability of an oil shale mine

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Summary

Stability in Exxon's Colony Pilot Mine in the Piceance Creek Basin, Colorado has been monitored by periodic pillar stress determinations and roof to floor convergence measurements since 1971. Pillar failure has caused marginal stability in some areas of the mine. Measurements taken during the process of failure provided valuable information on thein situ pillar strength and long-term behaviour of the mine structure. Four pillars were reinforced by 32 mm (1.25 in.) diameter tensioned grouted bolts to increase long-term stability in the northern area of the mine. Stability of this area is necessary because future plans envisage its use as an exit/access and ventilation exhaust.

Computer analyses were performed to help evaluate the effect of pillar reinforcement on long-term stability. Results indicate that bolting is particularly useful in stabilizing failed pillars, but its effects are significant only in the immediate area of the pillar. The projected significant decrease in deformation of two extensively failed pillars near a main entry indicates that bolting reinforcement will assist the long-term stability of the opening.

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References

  • Agapito, J.F.T. and Hardy, M.P. (1982) Induced horizontal stress method of pillar design in oil shale,Proceedings of the 15th Oil Shale Symposium, Colorado School of Mines, Golden, Colorado, pp. 179–191.

    Google Scholar 

  • Barton, N. (1973) Review of a new shear-strength criterion for rock joints,Engineering Geology 7, 287–332.

    Article  Google Scholar 

  • Goodman, R.E. (1974) The mechanical properties of joints,Proceedings of the Third Congress of the International Society for Rock Mechanics, Denver, pp. 127–40.

  • Mitchell, S.J., Agapito, J.F.T. and Weakly, L.A. (1984) Reinforcement of large pillars by bolting,Proceedings of the 25th US Symposium on Rock Mechanics, Northwestern University, Evanston, Illinois, June, pp. 523–32.

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  • St. John, C.M. (1978) Program EXPAREA: a computer program for analysis of test scale underground excavations for disposal of radioactive waste in bedded salt deposits, Oak Ridge National Laboratory, SUB 7118/2, April.

  • Weakly, L.A., Agapito, J.F.T., Aggson, J.R. and Maleki, H.N. (1984) The effect of various underground excavation methods on oil shale mine pillars,CMA 1984 Mining Yearbook, Denver, February, pp. 108–112.

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Authors and Affiliations

  1. J. F. T. Agapito and Associates, Inc., 715 Horizon Drive, 81501, Grand Junction, Colorado, USA

    J. F. T. Agapito & S. J. Mitchell

  2. Colony Oil Shale Project, Exxon Company, USA, Grand Junction, Colorado, USA

    L. A. Weakly

Authors
  1. J. F. T. Agapito
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  2. S. J. Mitchell
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  3. L. A. Weakly
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Agapito, J.F.T., Mitchell, S.J. & Weakly, L.A. Effect of pillar reinforcement on long-term stability of an oil shale mine. International Journal of Mining Engineering 3, 195–213 (1985). https://doi.org/10.1007/BF00880767

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  • DOI: https://doi.org/10.1007/BF00880767

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