Morphological evolution indicates the transformation of stress interference in parallel fractures

Fracture propagation is ubiquitous in natural strata and geological engineering, influencing processes such as accurately assessing engineering stability and optimizing design and construction. Prior studies have investigated the propagation mechanism of individual cracks through gelatin visualization experiments, while stress interference between cracks has been considered less. This study presents an innovative experimental approach, which establishes a connection between fracture morphology and stress interference through the mirror-symmetric dual fracture experiment. We identified distinct regions corresponding to varying levels of stress interference during fracture propagation. The results indicate that the region's transition occurs when the fracture radius grows to approximate the fracture spacing. We defined an influence factor (\((\beta)\)) to quantify the stress interference and analyzed regional transitions through variations of \((\beta)\). Finally, we constructed an analytical model for \((\beta)\) to depict the stress interference and obtained satisfactory consistency.