Development of an Intrinsically Safe, Integrated Wireless Communications Network with a Distributed Array of Geotechnical Sensors

For over 20 years, SCT Operations (SCT) have provided a range of industry standard geotechnical instrumentation, including Tell-Tales (Rock-IT/Clock-IT), instrumented bolts, three dimensional stress monitoring cells and shear strips. This project outlines the development of a wireless enabled strata monitoring system to integrate into the current Holville roofAlert™ real time communication and logging system. This provides a platform upon which to integrate a robust and cost effective distributed array of strata monitoring devices which then interfaces into existing coal mine ethernet and optical fibre communication infrastructure.

Wireless capability will enable the rapid deployment of geotechnical sensors, including SCT Rock-IT and Clock-IT roof monitoring at development roadway faces, providing immediate response to Trigger Action Response Plans and real time monitoring at surface. Valuable electronic data extracted from the roofAlert™ system can also be used for future mine roadway and support designs, eliminating the need for manual transfer of data.

In addition, wireless enabled instruments are also particularly suited to critical underground mining processes including longwall installation faces and recovery roads; where the small footprint and line of sight is particularly suited to wireless networks. Being recoverable, they also provide a cost-effective portable solution.

The instrumentation components developed for use in the system were all certified Intrinsically Safe (IS) for use in Australian coal mines. An IS handheld readout unit has also been developed as an additional monitoring option.