The Stability Factors’ Sensitivity Analysis of Key Rock B and Its Engineering Application of Gob-Side Entry Driving in Fully-Mechanized Caving Faces

Table 1

Experimental factors and levels.

Level	Factor
	Main roof height (m)	Main roof hardness (MPa)	Length of the key rock block B (m)	Fracture position of the main roof (m)
1	0	Soft/25	16	Inside the coal wall 2 m
2	5	Medium-hard/35	18	Right above the roadway
3	10	Hard/45	20	Outside the coal wall 2 m