hoek-brown

bulk f

bulk modulus, $K$

constant-a f

Hoek-Brown parameter, $a$

constant-dilation f

dilation angle, $\psi_c$, required only when flag-dilation = 0. The default is 0.0.

constant-mb f

Hoek-Brown parameter, $m_b$

constant-s f

Hoek-Brown parameter, $s$

constant-sci f

Hoek-Brown parameter, $\sigma_{ci}$

current-a f

current value of $a_c$

current-mb f

current value of $m_{b,c}$

current-s f

current value of $s_c$

current-sci f

current value of $\sigma_{ci,c}$

poisson f

Poisson’s ratio, $\nu$

shear f

shear modulus, $G$

tension f

current value of tensile strength, $\sigma^t$. The default is 0.0.

young f

Young’s modulus, $E$

flag-brittle b

[advanced] If true, the tension limit is set to 0 in the event of tensile failure. The default is false.

length-calibration f

[advanced] calibration length to calibrate model properties to account for zone size, default value is 0.0, which means that it does not perform length calibration to account for zone size.

flag-dilation f

= :[advanced] lint:$0$ (default flag) to input a constant dilation angle specified by constant-dilation

= -1 to specify associated plastic flow, $\psi_c$ = $\phi_c$

= k where k is a fraction of friction angle, $\phi_c$, so that $\psi_c$ = $k \times \psi_c$

flag-evolution i

= :[advanced] lint:$0$ (default flag) for evolution parameter set to plastic strain in direction of least compressive principal stress

= 1 for evolution parameter set to plastic shear strain, only acuumulated when shear yielding occurs

flag-fos i

= :[advanced] lint:$0$ (default flag) for model factor-of-safety solution controlled by shear strength

= 1 for model factor-of-safety solution controlled by unconfined compressive strength

table-a s

[advanced] name of the table relating $a$ to the evolution parameter.

table-m s

[advanced] name of the table relating $m_b$ to the evolution parameter.

table-multiplier s

[advanced] name of the table relating a multiplier to $\sigma_3$.

table-s s

[advanced] name of the table relating $s$ to the evolution parameter.

table-sci s

[advanced] name of the table relating $\sigma_{ci}$ to the evolution parameter.

table-tension s

[advanced] name of the table relating $\sigma^t$ to plastic tensile strain.

cohesion f

[read only] current value of cohesion, $c_c$

dilation f

[read only]current value of dilation angle, $\psi_c$, in any cases, this value never greater than the current friction angle.

friction f

[read only] current value of friction angle, $\phi_c$

strain-plastic f

[read only] plastic strain in direction of least compressive principal stress (if flag-evolution = 0), or plastic shear strain (if flag-evolution = 1)

Notes:

• Only one of the two options is required to define the elasticity: bulk modulus $K$ and shear modulus $G$, or, Young’s modulus $E$ and Poisson’s ratio $\nu$. When choosing the latter, Young’s modulus $E$ must be assigned in advance of Poisson’s ratio $\nu$.
• The tension cut-off is ${\sigma}^t = min({\sigma}^t, c/\tan \phi)$.
• There are two sets of parameters for ($a$, $m_b$, $s$, $\sigma_{sci}$): one is called constant set, which are the values assigned at the first time and remain constant thereafter; the other is called current set, which are automatically initialized as the same values of the constant set, but can be updated thereafter using tables or FISH functions if parameter evolution/update is involved, otherwise, the current set can be considered only for output.
• The tension table and flag-brittle should not be active at the same time.

Footnotes

Advanced properties have default values and do not require specification for simpler applications of the model.

Read only properties cannot be set by the user. However, they may be listed, plotted, or accessed through FISH.