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In practical work, wood substitutes should be sought as much as possible. Concrete prefabricated parts are used in many mines, but in the upper part of the prefabricated frame, wood wedges are needed to keep the concrete prefabricated when the roof is pressed. It has plasticity. In order to save the support material, the waste rock can be filled in the center of the hollow concrete to become a solid concrete, so as to withstand greater pressure.
Raft support method
When the top plate is partially soft or has fallen, and it cannot be supported by a single column or a column, it is suitable to use the raft support. The raft supports the pressure of the stope and can be a solid raft or a hollow raft.