Water Supply and Regulation of Underground Reservoir in Coal Mine considering Coal-Water Occurrence Relationship

Table 1

Physical and mechanical parameters of rock stratum.

Types of rocks	Bulk density kN/m^3	Compressive strength /MPa	Internal friction angle	Cohesion	Elastic modulus /GPa	Poisson’s ratio μ	Permeability coefficientc m/s
Aeolian sand	15.8	—	20	0.02	—	—
Conglomerate	23.9	45.3	39	7.10	33	0.25
Sandy mudstone	22.4	22.8	38	6.32	23	0.28
Siltstone	23.5	40.6	38	7.07	35	0.25
Coal	15.1	6.60	30	2.00	14	0.22
Mudstone	22.3	20.7	29	5.55	20	0.30
Fine sandstone	23.4	6.60	38	6.46	13	0.22