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

Table 2

Parameters of physical and mechanical properties of various coal and rock layers.

Model level	Thickness	Density	Adhesion	Friction angle	Bulk modulus	Shear modulus	Tensile strength
(m)	(kg/m^−3)	(MPa)	(°)	(GPa)	(GPa)	(MPa)
Sandstone	20	2500	16	36	16.3	13.5	2
Fine sandstone	5	2700	14	34	17.6	14.1	1.86
Direct top mudstone	4	2000	2	32	5.8	2.96	0.83
No. 2 coalbed	2	1400	0.35	18	1.15	0.33	0.15
Direct bottom mudstone	2	2000	0.86	28	3.8	1.96	0.45
No. 3 coalbed	1	1400	0.35	18	1.15	0.33	0.15
Sandstone	20	2500	16	36	16.3	13.5	2.2