Abstract
The fractographies of an artificial fracture that was formed by a blast and a natural fracture cutting chalks that display mirror planes and hackled fringes are similar. In both fractures the mirror and fringe are separated by clear boundaries, and the locations of the maximum hackle intensity and maximum φ angle (produced between the mirror plane and the fringe) coincide with the positions where segments of the mirror boundaries that have different curvatures meet. On both the natural and artificial fractures, radial hackles associated with the different boundary segments focus on distinct origins. The φ angle varies from 0° to 30°±5° on the natural joint and from 30°±8° to 50°±8° on the artificial fracture. The coinciding positions of hackle intensity and φ maxima observed in the two fractures match well with bifurcating fractures induced by experimental Hertzian fracture in Perspex. These are further supported by a geometric mismatch analysis. The present results demonstrate that the K I increases, which occur in positions where fractures of different ellipticities meet, enhance hackle intensity, crack-branching and the value of φ.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
