Research on the Reasonable Coal Pillar Width and Surrounding Rock Supporting Optimization of Gob-Side Entry under Inclined Seam Condition

Table 1

Testing result of coal samples about physical and mechanical properties.

Types	Density (g·cm^−3)	Bulk modulus (GPa)	Shear modulus (GPa)	Cohesion (MPa)	Internal friction angle (°)	Thickness (m)
Fine sandstone	2.70	13.3	10	10.2	37	5.0
Medium sandstone	2.34	12.3	9.1	5.2	37	13.0
Fine sandstone	2.70	13.3	10	10.2	37	5.0
Siltstone	2.65	9.1	7.8	7.2	34	5.0
Carbon mudstone	2.54	8.4	5.7	8.0	36	1.5
2# coal	1.30	5.0	2.1	1.68	28	8.5
Siltstone	2.65	9.1	7.8	7.2	34	5.0
Mudstone	2.25	6.8	4.8	6.2	26	2.0
Fine sandstone	2.70	13.3	10	10.2	37	5.0