Geological formations and structures in underground mines are often subject to significant levels of stress. Essentially, these stresses can be divided into two main types: static stress and dynamic stress.
Because static stress is mostly caused by the weight of the geological strata above a particular part of a mine, it is usually counteracted by the design and construction of a support system and other measures.
Dynamic stress, on the other hand, is usually caused by seismic activity, in particular mine induced seismicity due to the effect of blasting in or near the affected area. Therefore, many of the principles and practices used in static support design are not relevant to dynamic support design projects or are limited in their effectiveness by the different forces at play.
The effects of mine induced seismicity are amplified by greater stress, and this stress generally increases substantially the deeper the mine goes. As mining develops, it is becoming common for underground mines to reach depths of three kilometres. In some parts of the world, mines are even reaching depths beyond the four-kilometre mark.
These increasing depths, and the greater stresses that result, mean that the risk of rock bursting is higher, and this factor must be carefully managed.
Controlling and minimizing the risks associated with dynamic stress within an underground mine starts with a top-class dynamic support design. This is a highly specialised field, and design work of this nature should only be undertaken by skilled professionals who have performed a thorough investigation and assessment of all relevant factors.
The effectiveness of a dynamic support system is largely determined by the quality of the initial dynamic support design work.
Don’t take unnecessary risks. Let our experts from Mine Design Engineering (MDEng) handle all of your dynamic support design requirements.