Fatigue properties analysis of cracked rock based on fracture evolution process

Abstract

Fracture evolution process (initiation, propagation and coalescence) of cracked rock was observed and the force—displacement curves of cracked rock were measured under uniaxial cyclic loading. The tested specimens made of sandstone-like modeling material contained three pre-existing intermittent cracks with different geometrical distributions. The experimental results indicate that the fatigue deformation limit corresponding to the maximal cyclic load is equal to that of post-peak locus of static complete force-displacement curve; the fatigue deformation process can be divided into three stages: initial deformation, constant deformation rate and accelerative deformation; the time of fracture initiation, propagation and coalescence corresponds to the change of irreversible deformation.

Keywords

rock mechanics / fatigue properties / cyclic loading / fracture evolution / fatigue damage