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Abstract

A method for fault uncertainty and risk assessment based on the concept of stochastic simulation is presented herein. The method is applied and back-analysed using the data from mined out longwall panels at North Goonyella Mine (Queensland, Australia). The results from the case study and its back-analysis show that one, fault risk can be quantified and two, this quantified fault risk can be integrated into longwall design and assist decision making. A third observation is that basing fault risk assessment on known faults alone underestimates fault risk and as a result, its quantification through simulation has a major positive economic impact. A fourth and final observation is that fault risk quantification supports the evaluation of mineable coal reserves: a risk comparison of mined out coal seams with other areas allows for the comparison of different levels of quantified risk for a comparable longwall design. The study shows the contribution of the quantified risk approach to reducing coal mining investment risks due to faults, as well as facilitating more informed decisions.

Keywords

LONGWALL MINING FAULTS STOCHASTIC SIMULATION RISK ASSESMENT COAL RESERVES MINE DESIGN

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Quantification of fault uncertainty and risk assessment in longwall coal mining: stochastic simulation,back analysis,longwall design and reserve risk assessment

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