Failure Mechanism and Acoustic Emission Precursors of Coal Samples considering Bedding Effect under Triaxial Unloading Condition

Table 2

Test results of unloading and triaxial compression failure.

No.	σ1-σ3 (MPa)	σ3 (MPa)	σ3-σ3 (MPa)	ε1 (mm/mm)	ε3 (mm/mm)
V-S-1	48.52	—	—	0.007858	0.002635
V-S-2	53.63	—	—	0.008236	0.002963
V-S-3	49.63	—	—	0.008123	0.002852
V-X-1	47.82	5.32	4.68	0.006093	0.002592
V-X-2	45.36	6.65	3.35	0.005624	0.002501
V-X-3	46.23	5.86	4.14	0.005982	0.002526
T-S-1	38.87	—		0.006983	0.005563
T-S-2	43.26	—		0.007653	0.005687
T-S-3	40.15	—		0.007125	0.005601
T-X-1	37.21	6.26	3.74	0.005416	0.002631
T-X-2	35.60	5.20	4.80	0.005021	0.002539
T-X-3	36.01	5.22	4.78	0.005238	0.002602
P-S-1	33.67	—		0.005563	0.002922
P-S-2	38.56	—		0.006521	0.003126
P-S-3	35.63	—		0.006159	0.003096
P-X-1	31.30	4.52	5.48	0.004635	0.002731
P-X-2	29.63	4.63	5.37	0.004123	0.002601
P-X-3	30.12	5.06	4.94	0.004356	0.002698