Volume 32, Issue 2 (March 2009)

    Using High Speed Video Imaging in the Study of Cracking Processes in Rock

    (Received 17 December 2007; accepted 16 July 2008)

    Published Online: 2008

    CODEN: GTJOAD

      Format Pages Price  
    PDF 17 $25   ADD TO CART


    Abstract

    This paper presents the use of a high speed video system (high speed camera) in studying the crack initiation, propagation, and coalescence in rocks. Prismatic laboratory-molded gypsum and Carrara marble specimens, which contained either a single artificial flaw or a pair of artificial flaws, were tested in uniaxial compression. The front face of the specimen was monitored by a high speed camera. By adopting an appropriate frame rate (1000 to 24 000 frames/s) and image resolution (256 by 512 to 1024 by 1024 pixels) of the high speed camera, we were able to observe the abrupt and violent cracking processes in rocks. In particular, it was possible to distinguish shear and tensile crack mechanisms, which so far was not possible and subject to many discussions in rock mechanics. Distinguishing the cracking details allowed us to record and interpret the entire cracking sequence. The aims of this paper are twofold. First, it briefly addresses the capability of the high speed camera technology to set the stage. Second, and this is the major contribution, it presents two comprehensive examples of how the interpretation of high speed videos is carried out to retrieve useful information on the cracking processes in rocks.


    Author Information:

    Wong, L. N. Y.
    Massachusetts Institute of Technology, Cambridge, MA

    Einstein, H. H.
    Massachusetts Institute of Technology, Cambridge, MA


    Stock #: GTJ101631

    ISSN: 0149-6115

    DOI: 10.1520/GTJ101631

    ASTM International is a member of CrossRef.

    Author
    Title Using High Speed Video Imaging in the Study of Cracking Processes in Rock
    Symposium , 0000-00-00
    Committee D18