Study on Roof Breakage-Induced Roadway Coal Burst in an Extrathick Steeply Inclined Coal Seam

Table 2

Proportion of similar material.

Lithology	Width (cm)	Simulated strength (kPa)	Compressive strength (MPa)
Average strength roof	40	93	31
Oil shale	25	84	28
Oil shale and sandstone	9	120	40
Oil shale	2	84	28
Aluminum mudstone	7	54	18
Oil shale	4	84	28
Fine sandstone	2	135	45
Coal	32	46	15
Carbon mudstone	5	54	18
Siltstone	5	114	38
Average strength floor	29	93	31