Research on the Redistribution Law of Lateral Mining Stress and the Bearing Characteristics of Section Coal Pillar in Extra-Thick Fully Mechanized Top-Coal Caving Mining

Table 2

Mechanical parameters of the coal and rock.

Medium name	Shear modulus (GPa)	Bulk modulus (GPa)	Cohesion (MPa)	Friction angle (°)	Tensile strength (MPa)
Medium fine sandstone	1.62	1.71	2.6	35	0.62
Bedrock	1.04	1.14	3.3	33	0.82
Sandy mudstone	0.91	0.86	3.3	37.5	2.25
Coal seam	0.67	0.50	1.3	28	0.54
Fine sandstone	1.04	1.14	3.3	33	0.82
Coarse sandstone	1.54	1.68	3.3	35	0.40
Mudstone	2.04	2.15	1.6	37.4	0.41