Table 1 Arrangement of triaxial shear tests of soft rock.

From: Statistical damage constitutive model of soft rock based on Improved Hoek-Brown strength criterion

Serial number

Confining pressure (MPa)

Test method

A1

0.0

Axial loading

A2

5.0

Axial loading

A3

10.0

Axial loading

A4

15.0

Axial loading

A5

20.0

Axial loading

A6

25.0

Axial loading

A7

30.0

Axial loading

B1

20.0

Radial unloading confining pressure, axial pressure unchanged

B2

25.0

Radial unloading confining pressure, axial pressure unchanged

B3

30.0

Radial unloading confining pressure, axial pressure unchanged