Study of SCA-Induced Rock Crack Propagation under Different Stress Conditions Using a Modified Cohesive Element Method

Table 4

The P-l linear fit equations under the conditions of σ₁–σ₃ = 5 MPa.

Notch direction, θ (°)	Stress condition (MPa)	P-l linear fitting equations	Adjusted R^2	Crack initiation pressure, P0 (MPa)
0	(5,0)	l = 127.54345P − 704.87343	0.80767	5.5265
	(7.5,2.5)	l = 20.40528P − 201.65121	0.86493	9.8823
	(10,5)	l = 11.65431P − 183.93688	0.94212	15.7827
	(12.5,7.5)	l = 7.56828P − 150.47596	0.95267	19.8825
	(15,10)	l = 5.61437P − 142.98323	0.96422	25.4674
	(17.5,12.5)	l = 4.60247P − 142.83603	0.95935	31.0346
	(20,15)	l = 3.70937P − 131.56198	0.97198	35.4675
45	(5,0)	l = 87.80175P − 705.51258	0.86615	8.0353
	(7.5,2.5)	l = 17.68538P − 231.72743	0.89638	13.1028
	(10,5)	l = 9.49899P − 176.70845	0.96058	18.6029
	(12.5,7.5)	l = 6.35449P − 150.48197	0.9683	23.6812
	(15,10)	l = 5.23749P − 159.45243	0.98428	30.4444
	(17.5,12.5)	l = 4.10701P − 142.96515	0.9775	34.8100
	(20,15)	l = 3.35472P − 132.33265	0.96648	39.4467
90	(5,0)	l = 22.25843P − 69.97357	0.31616	3.1437
	(7.5,2.5)	l = 7.89522P − 163.5916	0.95204	20.7203
	(10,5)	l = 5.82953P − 153.31147	0.95795	26.2991
	(12.5,7.5)	l = 4.51084P − 138.39713	0.96233	30.6810
	(15,10)	l = 3.53828P − 120.16012	0.96753	33.9600
	(17.5,12.5)	l = 2.86423P − 106.77622	0.96722	37.2792
	(20,15)	l = 2.23186P − 84.21847	0.98777	37.7346