Abstract: The exploration causes the damage to the overburdens in Nanminghe Iron Mine and easily leads to the seepage of the upper water, which threatens the safety of mine. In order to guarantee the safety of the underground production, the strata pressure on-line monitoring system is adopted to monitor the displacement and abscission layer of the surrounding rock in the across vein roadway of Nanminghe Iron Mine in real time. The monitoring results show that the maximum value of the roof convergence is 9mm in the across-vein roadway with the strata-pressure behaviors not distinct. The research results showed that the mining under the ordovician limestone water was in safety by the current mining method.

Key words: Ordovician limestone water, Across-vein roadway, Strata-pressure behavior