On the Effects of Unparallel Cracks on the Mechanical and Fracturing Characteristics of Granite: Acoustic Emission (AE) Recording, Experimental Tests, and Numerical Simulations

Oblique (unparalleled) joints naturally occur in rock masses and significantly influence the mechanical properties, failure modes, and strength characteristics of rocks under various loading conditions. Discontinuities such as joints and faults are primarily associated with natural rocks and critically impact the strength and stability of rock engineering structures, including underground spaces. Therefore, extensive research is being conducted to investigate and understand the behavior of rock masses under different loading environments. For instance, Haeri et al. (2014a) and Haeri (2015) examined the strength and fracturing mechanisms of rock-like material samples under uniaxial compressive loading conditions. They visualized and explained the mechanisms of initiation, propagation, and coalescence of primary (wing or tensile) and secondary (shear) cracks within these samples, which contained pre-existing cracks under compression.