Study on the Stage Failure Mechanism and Stability Control of Surrounding Rock of Repeated Mining Roadway

Table 4

Rock mechanics parameters of the computation model.

Lithology	Bulk modulus (GPa)	Shear modulus of elasticity (GPa)	Density kg/m^−3	Cohesion (MPa)	The angle of internal friction (°)	Tensile strength (MPa)
Fine-grained sandstone	5.4	2.5	2500	15	39	2.67
Medium-grained sandstone	4.4	2.5	2500	4.6	32	1.7
Sandy mudstone	2.5	1.5	2440	3	27	0.95
2^−2 coal	2.2	1.5	1500	2.5	26	0.65
Sandy mudstone	2.5	2	2440	3.2	28	0.9
Siltstone	4.5	2.3	2500	1.2	33	2
Fine-grained sandstone	6.6	3.2	2500	1.4	35	2.67