Instability Analysis and Reinforcement Support Technology of Coal-Rock Interbed Roadway in Gaojiazhuang Coal Mine

Table 1

Lithological characteristics of No.2 coal seam.

Horizon	Lithology	Thickness (m)
Roof	Fine sandstone	5.2
	Direct top mudstone	2.5
Coalbed	No. 2 coalbed	1.75
Floor	Direct bottom mudstone	1.8
	No. 3 coalbed	1.1