Effect of foundation rigidity on stratified roadway roof stability in underground coal mines

The stability of roadway roof has been a long-standing issue in underground coal mines and thus has received a great deal of attention by both researchers and practitioners over the past few decades. This paper presents a simple analytical model for stratified roadway roof stability analysis. The model treats the immediate roof stratum of the roadway as an elastic beam resting on Winkler-type foundation and subjected to uniform roof loading that is determined from the lithology and depth of overlying strata. The developed model calculates bending stresses and deflections of the roof beam. Two case studies from an underground coal mine are used to demonstrate the model. A model parametric study reveals that the coal foundation elasticity plays a key factor in roof deformation and potential failure. Field monitoring data is used to validate analytical model results, and the comparison shows a good agreement.

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