Stress corrosion and interaction behaviour of adjacent cracks in rock-like material under hydro-mechanical Coupling: An experimental and numerical study

Under long-term hydro-mechanical coupling, the propagation of adjacent cracks present obvious time effect, and have significant influence on the progressive failure mode of rock-like materials. The creep tests were carried out based on the cement mortar specimen containing adjacent cracks, and the low-field Nuclear Magnetic Resonance (NMR) technology were used to evaluate the evolution of crack structure in the specimen. Based on the nu-merical simulation, the influences of the interaction behaviour between cracks on the time-dependent propa-gation of cracks and failure of specimens is revealed. The results show that: The specimen presents a tension-shear failure mode, and the macro fracture on its surface is Z-shaped; Crack interaction has an important role in promoting the formation and connection of microcracks, which increases the number of seepage channels and promotes the formation of the macro fracture; The propagation of adjacent cracks show significant asymmetry and non-uniformity, due to the stress superposition effects in the rock bridge area; The interaction between cracks is manifested as the inhibition of wing crack propagation in the rock bridge area at the initiation stage and then promotion effect at the later stage.