Analysis and Engineering Practice of Factors Affecting Top-Coal Recovery in a Large Dip Coal Seam

Table 2

Mechanical parameters of the coal and rock.

Rock	Thickness (m)	Density (kg/m^3)	Compression strength (MPa)	Tensile strength (MPa)	Friction angle (°)	Elastic modulus (MPa)	Poisson’s ratio
Sandy mudstone	7.60	2598	63.22	4.05	36	10233	0.26
Limestone	5.70	2688	76.02	5.10	29	11279	0.23
9# coal	11.80	1420	2.72	0.57	35	3865	0.33
Mudstone	1.89	2623	61.12	3.26	34	8179	0.29