Innovative Rehabilitation of Existing Tunnels Under Minimum Impact on Operation

Synopsis:

The authors have successfully developed an innovative rehabilitation concept, which meets actual technical standards and minimizes the impact on the operation of a key conveyor tunnel. A flexible and stepwise ground support rehabilitation program utilized a combination of yielding steel arch sections with grout filled fabric hoses, which represents a fast and safe backfilling support system.

The system was developed and successfully installed at Bingham Canyon Mine, the world’s largest open pit copper mine, which also includes numerous underground structures. The mine is owned and operated by Kennecott Utah Copper (RTKC) a fully owned subsidiary of Rio Tinto. The system was implemented at a conveyance tunnel, which was originally designed as a railroad tunnel, but was re-commissioned and is currently used as a conveyor belt tunnel to transport ore from the open pit to processing facilities outside the mine. The existing structure showed signs of overstressing due to movements in the surrounding rock mass, which had to be addressed with a yielding support system in order to provide safe access into the tunnel. However, the impact on the conveyor belt operation due to support installation was to be limited to the bare minimum.

2015 SME Annual Meeting
Feb. 15-18, 2015, Denver, Colorado, (Nitschke, A. G., Dase, J., Ossenbühl, I. & Dolsak, W.)

Copyright holds Society for Mining, Metallurgy & Exploration (SME). Full proceedings volumes can be found on website at www.smenet.org.