Research Article
Study on the Key Technology of Controlling the Instability of Deep High-Stress Coal and Rock Mass and Relieving the Danger
Table 1
Statistics of noise coal gun in the roadway.
| Date | Frequency of sound | Frequent noise frequency | Sound frequency | Position |
| February 20th | 12 | 8 o’clock | 6 | Middle of roof | February 21th | 2 | 4 o’clock | 1 | Roof fracture | February 22th | 2 | 8 o’clock | 2 | — | February 23th | 13 | 8 o’clock | 8 | Wind tunnel gang | February 24th | 15 | 8 o’clock | 7 | There are 4 air ducts and two pedestrians | February 25th | 13 | 8 o’clock | 9 | Air duct, pedestrian, 10–15 m from head to back 10-15 m | February 26th | 2 | 8 o’clock | 9 | — | February 27th | 6 | 4 o’clock | — | — | February 28-29th | 0 | — | — | — |
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