Ever increasing depth of mineral extraction presents a challenging environment for hard rock underground mines. High in situ stresses and associated seismicity with potential rock burst hazards are the major decisive factors contributing to the choice of a ground support regime. Conventional ground support systems, designed primarily for static loads, are not always capable of providing safe working conditions for underground personnel in seismically active mines. Systems specifically developed to resist dynamic loading and allowing for larger deformations are therefore preferred alternatives.
High-tensile chain-link mesh has a proven record of successful use in open cut operations in various rockfall barrier installations due to its high energy absorption capacity. It has also been used in underground operations in various parts of the world. Its application in Australian underground mining, however, is limited due to the high labour intensity. This paper describes a method of mechanised installation of a chain-link mesh as trialled at Golden Grove, a base metals underground mine in Western Australia.
A purpose-built mechanised roll mesh handler, developed in Australia, was used in this trial. The handler is compatible with all standard multi-boom underground drill rigs and is operated utilising the hydraulic circuit normally used for the feed arrangement.
A number of operational benefits have been identified during the trial, the main two being:
•improved safety of underground personnel due to the reduced amount of manual handling, and
•increased productivity due to the decreased cycle time (the trial suggests a 40 – 50 per cent reduction in time over the weld mesh installation method).
the energy-absorbing mesh combined with yielding rock bolts is a ground support
system of choice for rock burst prone conditions, the operational upsides
recognised during the trial imply that this product can also be competitively
used in less demanding ground conditions where customarily weld mesh or
shotcrete are used as a primary surface support.
Brown, S and Bucher, R, 2011. Fast, safe and fully
mechanised installation of high-tensile chain-link mesh for underground support,
in Proceedings 11th AusIMM Underground Operators’
pp 127-134 (The Australasian Institute of Mining and