The practice cf mining room first and then pillars by overhand cut and cemented fill is widely used in China, but the condition for pillars recovery in later period is normally worse.

先房后柱的上向分层胶结充填法在我国应用较为广泛，但矿柱后期回采条件较差。

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The practice cf mining room first and then pillars by overhand cut and cemented fill is widely used in China, but the condition for pillars recovery in later period is normally worse.

先房后柱的上向分层胶结充填法在我国应用较为广泛，但矿柱后期回采条件较差。

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