Design of temporary rock support for SFR
LKAB’s Kiirunavaara Mine is a large, underground, sub-level caving mine that has been seismically active since approximately 2008. With this seismic activity comes associated vibrations. These vibrations can be felt on surface in the town of Kiruna, which is currently located close to the mine on the hangingwall side. The mine is undergoing a national permitting process concerning a desired increased production rate. An important question for this process is: will the increased production rate result in changes to vibrations in the town due to seismicity?
Itasca has helped LKAB by answering this question using state-of-the-art knowledge and techniques. First, we worked with LKAB to statistically understand seismicity and vibrations at the mine. Then, we built a 3-D numerical stress analysis model to conduct detailed analyses concerning historic seismicity so we could make judgements about the influence of the planned production on future seismicity. Indicators in the model of crack initiation and potential movement along pre-existing discontinuities were used as comparators to seismically active volumes which likely contributed to vibrations on surface.