Numerical Investigation of Influences of Drilling Arrangements on the Mechanical Behavior and Energy Evolution of Coal Models

Table 4

Mechanical properties of specimens with different drilling arrangements.

Test scheme	RD (mm)	NH	NR	σc (MPa)	E (GPa)	ε1max (10^−2)
I	3	1	1	11.48	0.66	1.7863
	5			11.17	0.65	1.7551
	8			9.89	0.64	1.5766
	10			8.64	0.63	1.3926
II	3	1	1	11.48	0.66	1.7863
		2		11.41	0.65	1.7804
		3		11.01	0.65	1.6993
		4		10.46	0.64	1.651
III	3	3	1	11.01	0.65	1.6993
			2	10.63	0.64	1.6833
			3	9.91	0.63	1.5857
			4	9.63	0.62	1.5785