Roof Water Damage Prediction and Evaluation of Sand-Mud Sedimentary Tectonic Strata

Table 1

Properties of coal and rock mass used in the numerical model.

Rock character	Poisson’s ratio	Density (kg·m^-3)	Cohesion (MPa)	Internal friction angle (°)	Bulk modulus (GPa)	Shear modulus (MPa)	Tensile strength (MPa)
Mudstone	0.25	2470	1.78	25	2.41	4.13	0.70
Siltstone	0.22	2602	3.10	33	7.21	2.80	0.80
Gritstone	0.32	2700	6.20	34	4.80	2.20	3.00
Fine sandstone	0.20	2590	3.96	50	6.98	2.80	1.35
Sandy mudstone	0.27	2490	1.79	26	2.44	4.23	0.75
Coal	0.31	1347	1.21	30	2.13	1.35	0.12