The effect of surface roughness and mixed-mode loading on the stiffness ratio κx/κz for fractures

摘要: ABSTRACTThe characterization of fractures using elastic waves requires a parameter that captures the physical properties fracture. Many theoretical and numerical approaches for wave propagation in fractured media use normal shear fracture specific stiffness to represent complexity topology as it deforms under stress. Most effective medium assume are equal, yielding shear-to-normal ratio one. Yet several experimental studies show this can vary from zero three. We conducted series experiments determine with different surface roughness subjected mixed-mode loading conditions. Specimens containing single were either or combined during ultrasonic measurements transmitted reflected P- S-waves. Theoretical analysis based on displacement discontinuity theory shows, ...