Table 1 Correspondence table of impact ground pressure accidents and load three-band state.

From: Theoretical framework and reliability verification of the loaded three-zone structural model in coal mine overburden strata

Date

Load three-zone pattern

Two-sided displacement/mm

Bottom drum /mm

Roof damage pattern

Roadway damage length/m

2014.9.5

Degenerate three-band structure

200

150

Roof convergence

38

2014.9.14

Degenerate three-band structure

Roof convergence

50

2015.1.9

Complete three-band structure

 ≥ 1000

 > 2000

Roof falling

155