Increasing Permeability of Coal Seam and Improving Gas Drainage Using a Liquid Carbon Dioxide Phase Transition Explosive Technology

Table 1

Mechanical properties of each geological unit.

Lithology	Modulus of elasticity E (GPa)	Uniaxial compressive strength σc (MPa)	Uniaxial tensile strength σf (MPa)	Poisson’s ratio	Friction angle (°)
Sandy mudstone	17.3	31.1	2.45	0.23	32
Coal	5.2	13.6	1.68	0.3	29
Mudstone	11.4	25.3	1.87	0.29	30