${\mathbf{D}}^e,{\mathbf{D}}^{ep}$	Elasticity tensor and elasto-plastic tangent operator.
E	Relative error norm of two estimated stresses.
$e,e_{cs}$	Void ratio and critical void ratio.
$F,g$	Bounding surface and plastic potential surface.
$G_{S1},G_{SN}$	Secant moduli at loading cycles 1 and N.
$h_b,h_f$	Plastic modulus at image stress and interpolation plastic modulus.
h	Plastic modulus at true stress.
$k_0,k_1,k_2$	Cyclic plasticity parameters.
$K,G$	Bulk modulus and shear modulus.
$k_f,d$	Hardening parameter and damage parameter.
L	Loading index.
$M_{cs}$	Critical stress ratio.
$m_p$	Length of the normal vector to plastic potential.
$n,r$	Bounding surface shape parameters.
$\tilde{\mathbf{n}},\mathbf{m}$	Normal vectors to the bounding surface and plastic potential.
$(op,oq)$	Projection centre coordinates.
$p_c^{\prime },{\overline{p}}_c$	Preconsolidation pressure and hardening internal variable of bounding surface.
${\overline{p}}^{\prime },\overline{q}$	Image stress on the bounding surface.
$p^{\prime },q$	Mean effective stress and deviatoric stress.
t	Parameter used to distinguish cyclic shakedown and failure.
T	Pseudo time.
v	Specific volume.
$\beta$	Scaling factor of sub-increment size.
$\gamma$	Distance ratio.
${\mathsf{\Gamma }}_o$	Intersection point of the CSL and the void ratio axis at $p^{\prime }=1$.
${\epsilon }_v,{\epsilon }_s$	Volumetric strain and shear strain
${\epsilon }_d^p,{\epsilon }_v^p$	Plastic deviatoric strain and plastic volumetric strain.
${\epsilon }_{c1},{\epsilon }_{cn}$	Cyclic axial strains at cycles 1 and N.
${\epsilon }_1,{\epsilon }_3$	Axial strain and lateral strain.
$\mathit{\epsilon },{\mathit{\epsilon }}^e,{\mathit{\epsilon }}^p$	Total strain tensor, elastic strain tensor and plastic strain tensor.
$\kappa$	Elastic slope in $e-\ln p^{\prime }$ space.
$\lambda$	Slope of the normal consolidation line.
$\mathsf{\Lambda }$	Plastic multiplier.
$\mu$	Poisson’s ratio.
$\overline{\rho }$	Euclidean distance between image stress and projection centre.
$\rho$	Euclidean distance between image stress and true stress.
${\sigma }_1^{\prime },{\sigma }_3^{\prime }$	Axial and lateral effective stresses.
${\sigma }_d$	Magnitude of axial cyclic stress.
${\mathit{\sigma }}^{\prime },{\overline{\mathit{\sigma }}}^{\prime }$	Effective stress tensor and the corresponding stress on bounding surface.
$\varphi$	Drained friction angle.