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European coal mines experience more roof closure, floor heave and side squeeze than most other coal mines from around the world due to the necessity to mine at great depths and the low material strength properties of the strata in which mining takes place.The weak strata surrounding the coal seams become increasingly vulnerable to degradation over time, especially when they are exposed to weathering by air and water.The consequences of such degradation are significant increases in the risk and uncertainty of mining, the costs of providing adequate support and an ultimate reduction in the mines productivity.