Table 2 Critical point parameters.

From: Creep failure characteristics and damage creep model of red layer soft rock based on Perzyna viscoplastic theory

σ3, (MPa)

Axial stress, (MPa)

t1, (h)

\(\varepsilon_{{t_{1} }}\), (%)

t2, (h)

\(\varepsilon_{{t_{2} }}\), (%)

σ3, (MPa)

Axial stress, (MPa)

t1, (h)

\(\varepsilon_{{t_{1} }}\), (%)

t2, (h)

\(\varepsilon_{{t_{2} }}\), (%)

5

26.26

5.08

0.114

–

–

10

32.87

5.10

0.121

–

–

31.57

4.42

0.132

–

–

40.52

4.86

0.133

–

–

36.76

4.04

0.168

–

–

47.27

4.44

0.175

–

–

42.01

3.66

0.216

–

–

54.02

3.82

0.236

–

–

47.26

2.05

0.228

10.04

0.249

60.78

2.26

0.261

13.32

0.277

15

40.09

5.20

0.146

–

–

20

48.16

5.33

0.148

–

–

48.11

5.02

0.177

–

–

57.79

5.09

0.181

–

–

56.13

4.76

0.218

–

–

67.42

4.76

0.225

–

–

64.15

4.01

0.276

–

–

77.05

4.14

0.281

–

–

72.17

3.15

0.319

19.08

0.328

86.68

3.28

0.324

19.72

330