Experimental Study on Damage and Gas Migration Characteristics of Gas-Bearing Coal with Different Pore Structures under Sorption-Sudden Unloading of Methane

Table 1

Proportion scheme and pore structure of coal samples used in the experiments.

Samples	Proportion scheme	Porosity (%)	Specific surface area (m^2/g)
C-1	0.38–0.83 mm, 225 g	14.58	24.40
C-2	0.38–0.83 mm, 122.5 g + 0.18–0.38 mm, 122.5 g	15.63	25.02
C-3	0.18–0.38 mm, 225 g	15.87	26.16
C-4	0.18–0.38 mm, 122.5 g + 0.12–0.18 mm, 122.5 g	16.09	27.64
C-5	0.18–0.12 mm, 225 g	16.52	29.35