ABSTRACT
The Sandvik MDX bolt has been developed to provide strata support in a wide variety of rock conditions (weak and competent), and in particular seismic rock conditions. While the MDX bolt maintains the key features of the successful MD bolt, regarding the ease of installation (single pass with no grout or resin required), its performance in both the seismic and very weak rock conditions has been significantly improved. The MDX bolt development was undertaken in conjunction with Telfer Gold Mine, located in Western Australia. Telfer mining operation employs three mining methods in a high stress and seismic setting. This setting was selected for trial dynamic testing of the MDX bolt, using a unique, world first in-situ Dynamic Test Rig. The performance requirements set out by Telfer were to withstand an impact energy of 25 kJ, and limit displacement to 200 mm. The results were more than satisfactory, as the maximum bolt displacement was only 153 mm.
