Mechanical and Coal Burst Breeding Mechanism of Coal Samples under True Triaxial Loading and Unloading

Table 2

Experimental conditions.

Influencing factor	Coal sample number	X/Y/Z axial stress/MPa	Unloading rate (mm·min^−1)	Loading rate (mm·min^−1)	RURLR
RURLR	G	20/20/20	0.56	1.5	0.4
	I	20/20/20	0.97	2	0.5
	H	20/20/20	0.84	1.5	0.6
	K	20/20/20	1.09	2	0.5
	L	20/20/20	1.18	1.5	0.8
	J	20/20/20	0.98	1	1.0
	B	20/20/20	1.08	1	1.1
	A	20/20/20	0.77	0.5	1.5
	C	20/20/20	0.85	0.5	1.7
	D	20/20/20	0.72	0.25	2.9
	E	20/20/20	0.80	0.25	3.2
Initial loading lateral stress	O	20/10/20	0.83	1.5	0.6
	H	20/20/20	0.84	1.5	0.6
	P	20/40/20	0.84	1.5	0.6
Initial unloading lateral stress	F	20/20/10	0.83	1.5	0.6
	H	20/20/20	0.84	1.5	0.6
	Q	20/20/40	0.83	1.5	0.6
Initial fixed lateral stress	S	10/20/20	1.15	1.5	0.8
	L	20/20/20	1.18	1.5	0.8
	R	40/20/20	1.13	1.5	0.8