Damage Constitutive Model of Microcrack Rock under Tension

Figure 5

Calculation model of the crack propagation criterion: (a) initial tension problem with cracks; (b) a 2-D plane element with a mode-I (open) crack in the centre with uniaxial tension in the y-direction; (c) a 2-D plane element with mode-I crack in the centre with uniaxial tension in the x-direction; and (d) a 2-D plane element containing a mode-II (slit) crack subjected to uniform shear.

(a)

(b)

(c)

(d)