Developing a numerical tool to optimise mining sequences and minimize seismic hazard using mine stiffness concept

Important results from the project

The aim of this project was achieved. Numerical tool used to assess burst potential for discontinues in deep underground mines was developed by implementing the loading stiffness concept and a new technique for seismic source parameters calculation. A modelling-based methodology for evaluating seismic hazard and choosing mining sequence for the Kiirunavaara underground mine was proposed. By implementing the methodology in practice, the number of production disturbances, and the risk for personnel injury and production losses could be reduced.

Expected long term effects

The expected results from this project comprise a numerical tool for assessing burst potential of discontinuities based on the stiffness criterion, and a new analysis technique which can be applied with greater confidence for providing insight into seismic hazard evaluation. The numerical tool can be used for optimising mining sequence at the LKAB’s Kiirunavaara Mine. The guidance gained may be used to minimise seismic hazard in the mine and ultimately be applied to improve mining safety.

Approach and implementation

The study comprised: seismic data analysis, numerical model development, model calibration, evaluation of mining sequences on burst potential, and development of guidance. Three damaging seismic events were chosen in model calibration after seismic data analysis. The seismic source parameters were calculated from the numerical model and compared with the collected seismic data. Various mining sequences were simulated and then the effect on seismic hazard was investigated and evaluated. A guideline was proposed for optimizing the mining sequences for the mine.