Due to their nature, construction, and typical location, the operational status, safety, and productivity of underground mines (whether hard rock or soft rock) are heavily dependent on the geology and behaviour of rock masses in and around the mine.
Because it is a highly variable material that exhibits significant variations in strength and the way it reacts to stresses, both natural and those caused by the dynamic conditions created by mining, rock within underground mines can be extremely difficult to engineer. Additionally, the deeper mines go, the more stresses increase.
Mine engineers must constantly contend with the risk of breakout (dog-earing) in excavations, stress induced fracturing (spalling), rock wall buckling, “hour-glassing” of pillars, convergence, shearing, and other rock behaviours that threaten mine safety and productivity, caused wholly or in part by factors such as:
- Blast fracturing that can create damage zones around excavations
- Changes to the stress regime in a rock mass when material is excavated
- Moist air from ventilation systems can lead to slaking that degrades rock strength
- Water from drilling and groundwater can lubricate rock structure, affecting strength and potentially leading to failure.
Knowing exactly what is happening within all rock masses in the mine is vital for proper planning, monitoring, and decision-making. Where required, the implementation of the correct countermeasures is heavily dependent on a full understanding of the status and behavior of all rock masses in the mine.
The strategic and appropriate use of a range of accurate, properly designed, and well-manufactured geotechnical monitoring instrumentation should be a vital part of all planning and operational monitoring activities within modern underground mines.
The data gathered from geotechnical monitoring instrumentation helps mine engineers to make better, more-informed decisions that balance the often-competing aspects of safety and production.
Click here to find out about the MDT range of high-quality, geotechnical monitoring instrumentation.