Experimental Investigation on Seepage Stability of Filling Material of Karst Collapse Pillar in Mining Engineering

Table 2

The seepage property parameters.

Specimen	Initial porosity	Initial permeability k0 (10^−14 m^2)	Stable permeability ks (10^−14 m^2)	Seepage instability duration T(s)
With clay	0.11	2.83	—	278
	0.13	4.64	—	180
	0.15	7.80	—	77
	0.17	14.38	—	34
With gypsum	0.11	1.85	0.49	—
	0.13	3.10	1.09	—
	0.15	3.69	—	5996
	0.17	4.99	—	4003
With cement	0.11	1.70	0.13	—
	0.13	2.18	0.29	—
	0.15	2.65	0.44	—
	0.17	4.89	1.11	—