Mechanical Mechanism and Propagation Law of Fissure-Tip Cracks of Large-Size Rock Specimens with Two Precut Fissures

Table 3

The numbers, lengths, and positions of the major cracks.

Specimen	Inner tip crack	Total length (mm)	Numbers	Angles between the wing cracks and the fissure plane (°)	Angles between the secondary coplanar cracks and the fissure plane (°)	Angles between the secondary inclined cracks and the fissure plane (°)
A-1	Upper crack	145	2	−112	−10	—
	Lower crack	284	3	−106, −45	—	83
A-2	Upper crack	108	2	−70	—	92
	Lower crack	140	3	−105	11	85
B-1	Upper crack	152	2	−135	—	150
	Lower crack	124	2	−62, −81	—	—
B-2	Upper crack	82	2	−94, −78	—	—
	Lower crack	126	2	−108, 65	—	—
C-1	Upper crack	138	3	−30,−85	—	25
	Lower crack	145	3	−66	−10	−62
C-2	Upper crack	87	2	−20, −72	—	—
	Lower crack	120	2	−55	—	94