Investigation on Crack Coalescence Behaviors for Granite Containing Two Flaws Induced by Cyclic Freeze-Thaw and Uniaxial Deformation in Beizhan Iron Mining, Xinjing, China

Table 2

Crack propagation and coalescence for the samples with an inclination flaw of 20°.

Failure morphology
Crack coalescence patterns	(i) Tensile cracks initiated from the flaw tips and almost parallel to the major stress direction; (ii) failure by only tensile or tensile+shear cracks; (iii) crack propagation from the left part of the inclined flaw to the middle of the horizontal flaw; (iv) plenty of cracks exist at the rock bridge	(i) Crack propagation from the left of the inclined flaw and propagation to the middle of the horizontal flaw; (ii) crack propagation from the right tip of the horizontal flaw to the middle of the inclined flaw; (iii) tensile failure occurs at the rock bridge and failure	(i) Crack propagation from the middle of the inclined flaw to right tip of the horizontal flaw, multiple tensile cracks initiated from the left of the horizontal flaw; (ii) shear crack initiated from the left tip of the inclined flaw; (iii) failure by only tensile crack; (iv) two cracks exist at the rock bridge	(i) Crack propagation from the left of the inclined flaw to the middle of the horizontal flaw; (ii) failure by only tensile crack; (iii) crack propagation from the right of the horizontal flaw to the middle of the inclined flaw; (iv) number of cracks at the rock bridge gets to the minimum