Study of Strength and Deformation Evolution in Raw and Briquette Coal Samples under Uniaxial Compression via Monitoring Their Acoustic Emission Characteristics

Table 1

Test results on coal sample uniaxial compression.

Coal sample type	Designation	Rc/MPa	ET/GPa	μ	∑A/x 10^6	∑N/x 10^5	∑E/x 10^5
Raw coal samples	MB1	4.82	1.49	0.22	2.01	7.69	9.07
	MB3	6.23	1.70	0.21	1.52	4.88	6.16
	MB4	2.36	0.91	0.20	1.53	4.11	4.73
	MB6	3.93	1.74	0.22	0.97	1.54	1.97
	MB7	3.94	1.37	0.22	2.72	6.82	11.86
	MH3	4.76	1.60	0.09	0.47	3.38	3.53
	Average	4.34	1.47	0.19	1.54	4.74	6.22
Briquette coal samples with a 0% cement content	MS8	1.38	0.12	0.24	1.60	0.62	0.58
	MS9	1.53	0.13	0.34	3.85	1.30	1.56
	MS10	1.58	0.12	0.22	1.32	0.68	0.49
	Average	1.50	0.12	0.27	2.26	0.87	0.88
Briquette coal samples with a 5% cement content	M2-2	2.77	0.23	0.12	3.36	1.41	1.54
	M2-3	3.11	0.25	0.16	3.10	1.21	1.23
	M2-4	3.28	0.28	0.19	3.69	1.43	1.35
	Average	3.05	0.25	0.16	3.38	1.35	1.37
Briquette coal samples with a 10% cement content	M3-1	3.31	0.29	0.08	3.70	1.45	1.80
	M3-2	3.30	0.28	0.11	3.70	1.45	1.80
	M3-3	3.45	0.28	0.11	4.50	1.46	2.06
	Average	3.35	0.28	0.10	3.97	1.45	1.89
Briquette coal samples with a 20% cement content	M4-1	4.76	0.45	0.13	5.30	1.76	3.43
	M4-2	4.57	0.48	0.11	4.54	1.46	2.60
	M4-3	5.13	0.54	0.08	4.07	1.35	2.19
	Average	4.82	0.49	0.11	4.64	1.52	2.74