Disaster Control of Roof Falling in Deep Coal Mine Roadway Subjected to High Abutment Pressure

Table 1

Physical and mechanical parameters of rock stratum.

Lithology	Density (kg/m^3)	Bulk modulus (GPa)	Shear modulus (GPa)	Internal friction angle (°)	Cohesive force (MPa)	Tensile strength (MPa)	Remark
Mudstone	2540	2.35	1.52	32	1.7	1.57
Fine sandstone	2831	3.22	1.80	35	2.3	2.24
Mudstone	2450	1.25	1.66	37	2.1	1.60
Siltstone	2635	2.16	1.23	39	3.3	1.80
Fine sandstone	2632	4.12	2.30	33	3.3	2.89	Main roof
Mudstone	2643	0.96	0.93	30	1.5	0.87	Immediate roof
3# coal seam	1401	0.68	0.50	26	0.9	0.41
Mudstone	2651	2.55	1.52	42	2.6	2.00	Floor
Siltstone	2645	2.57	1.54	34	2.5	2.68