Permeability Evolution and Particle Size Distribution of Saturated Crushed Sandstone under Compression

Table 7

The values of parameters used to calculate the permeability.

(a) n = 0.2

Axial stress; (MPa)	Pore water pressure gradient; (MPa/m)	Water flow velocity; (10^−3 m/s)	Permeability; (10^−14 m^2)
0	5	4.43	56.67
	10	5.59
	15	7.42
	20	12.31
2	5	1.42	21.16
	10	1.91
	15	2.91
	20	4.21
4	5	0.57	8.29
	10	0.79
	15	1.03
	20	1.60
8	5	0.39	5.50
	10	0.47
	15	0.66
	20	0.99
12	5	0.27	3.48
	10	0.35
	15	0.47
	20	0.78
16	5	0.26	4.14
	10	0.39
	15	0.51
	20	0.76

(b) n = 0.4

Axial stress; (MPa)	Pore water pressure gradient; (MPa/m)	Water flow velocity; (10^−3 m/s)	Permeability; (10^−14 m^2)
0	5	4.57	59.72
	10	5.24
	15	7.29
	20	11.40
2	5	1.52	23.96
	10	2.19
	15	2.87
	20	4.26
4	5	0.72	10.37
	10	0.88
	15	1.64
	20	2.24
8	5	0.32	4.89
	10	0.41
	15	0.63
	20	0.88
12	5	0.36	5.73
	10	0.49
	15	0.73
	20	1.02
16	5	0.32	4.77
	10	0.43
	15	0.59
	20	0.88

(c) n = 0.6

Axial stress; (MPa)	Pore water pressure gradient; (MPa/m)	Water flow velocity; (10^−3m/s)	Permeability; (10^−14m^2)
0	5	4.45	63.40
	10	5.77
	15	8.12
	20	12.28
2	5	1.86	27.08
	10	2.77
	15	3.39
	20	5.46
4	5	0.96	12.83
	10	1.11
	15	1.56
	20	2.40
8	5	0.52	7.52
	10	0.72
	15	0.91
	20	1.43
12	5	0.50	7.55
	10	0.68
	15	0.99
	20	1.44
16	5	0.43	6.35
	10	0.48
	15	0.65
	20	0.96

(d) n = 0.8

Axial stress; (MPa)	Pore water pressure gradient; (MPa/m)	Water flow velocity; (10^−3 m/s)	Permeability; (10^−14 m^2)
0	5	3.99	67.16
	10	5.85
	15	8.40
	20	11.68
2	5	2.32	30.15
	10	2.82
	15	4.01
	20	6.37
4	5	1.15	15.67
	10	1.39
	15	1.93
	20	2.97
8	5	0.57	8.75
	10	0.81
	15	1.12
	20	1.66
12	5	0.62	9.09
	10	0.81
	15	1.15
	20	1.70
16	5	0.39	6.14
	10	0.54
	15	0.71
	20	1.05