Numerical modelling of shaft lining stability at deep mine

Abstract

During the last thirty years, the Boulby Potash Mine has replaced the concrete shaft linings in sections of both shafts on two occasions following progressive deterioration. A third replacement lining is now under construction in the man shaft. This paper reports the results of two-dimensional (2D) and three-dimensional (3D) numerical modelling of the shaft linings and their surrounding strata. The numerical modelling, using FLAC^2D and FLAC^3D has considered the detrimental effect to lining stability of a weak rock zone surrounding the shafts at depth. The 3D modelling work has also taken into account the formation of an inset and roadway leading from the shaft. This research aimed to identify the failure mechanisms of the shaft linings in the affected zone and their causes. The research also supplied reference data to allow the prediction of stress and deformation conditions in the newly designed third shaft relining system.

Keywords

Numerical modelling Shaft lining stability Weathered rock zone

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