How to close the gob, what are the applicable conditions?

In the closed goaf, in the roadway leading to the goaf, a partition wall of a certain thickness is built, so that the impact waves generated by the collapse of the surrounding rock in the empty area can be buffered when the partition wall is encountered. This method is suitable for the condition that the empty area is not large and is far away from the main production area , and the lower part of the empty area is no longer subjected to the mining work . For processing large gap, only a sealing method auxiliary means, such as a closed tunnel communication and transport ore chute, pedestrian courtyards.

The closed method is used to treat the goaf, and the upper overburden should be allowed to collapse, otherwise it cannot be used.

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