3-D	three-dimensional
DIC	digital image correlation
FE	finite-element
ITZ	interface transition zone
d	diameter of each grading class
$d_c$	compression scalar stiffness degradation variable
$d_{max}$	maximum aggregate diameter
$d_{min}$	minimum aggregate diameter
$d_t$	tensile scalar stiffness degradation variable
D	scalar stiffness degradation variable
$E_c$	Young’s modules of the weaker concrete
$E_{ho}$	homogeneous Young’s modulus
$E_m$	Young’s modules of the mortar
${E^{pl}}_0$	initial elastic modulus
G	flow potential
$G_c$	Kirchhoff’s modules of the weaker concrete
$G_f$	fracture energy
K	stiffness matrix
$K_c$	ratio of the second stress invariant of the tensile meridian to that of the compressive meridian
$\mu$	frictional coefficient
n	exponent of the chosen grading curve
N	amount of aggregates
$\overline{p}$	effective hydro-static pressure
P	loading force
$P\left(d\right)$	corresponding passing percentage
$\overline{q}$	Mises equivalent effective stress
$q_{cm}$	compression meridian
$q_{tm}$	tensile meridian
t	nominal traction stress vector
$T_0$	original thickness of the cohesive element
$T_{eff}$	effective traction
$U_{t0}$	cracking displacement
V	volume of the concrete sample
$V_e$	equivalent volume of a single aggregate
$v_P$	volume fraction of aggregates
$w_P$	total weight of aggregate particles
$\alpha$	characteristic parameter of yield function, $\alpha$
$\beta$	characteristic parameter of yield function, $\beta$
$\gamma$	characteristic parameter of yield function, $\gamma$
$\delta$	separation
$\epsilon$	strain
${\epsilon }^{pl}$	plastic strain
$ϵ$	parameter, referred to as the eccentricity of materials
$\psi$	dilation angle
$\nu$	Poisson’s ratio
$V_p$	specific weight
$\sigma$	Stress
$\overline{\sigma }$	effective stress
${\sigma }_{b0}$	initial equi-biaxial compressive yield stress
${\sigma }_{c0}$	initial uniaxial compressive yield stress
${\sigma }_{cf}$	compression failure stress
${\sigma }_{cy}$	yield stress,
${\sigma }_{t0}$	tension strength
${\sigma }_{tf}$	tension failure stress
$\varsigma$	module parameter of mortar