Fracture initiation in cavity expansion of rock

Ali Tarokh, Derrick J. Blanksma, Ali Fakhimi, Joseph F. Labuz

Research output: Contribution to journalArticlepeer-review

22 Scopus citations


Initiation of fracture from a cylindrical opening in blocks of Berea sandstone under plane strain was monitored with a cavity expansion apparatus. Using the particle tracking technique called digital image correlation, a discontinuity in the displacement field near the cavity boundary was identified at 80% of the peak internal pressure, which meant that a process zone developed prior to peak. To investigate the effect of scaling on fracture, a two dimensional bonded particle model was validated, and several specimens sizes with different borehole and tension softening characteristics were tested numerically. It is demonstrated that with increase in specimen size or with increase in borehole size, the peak pressure decreases, and these size effects are governed by both material and structural length scales.

Original languageEnglish (US)
Pages (from-to)84-91
Number of pages8
JournalInternational Journal of Rock Mechanics and Mining Sciences
StatePublished - May 1 2016

Bibliographical note

Funding Information:
Partial support was provided by the MSES/Kersten Chair . Professors Y. Mizuta and T. Ishida designed the cavity expansion apparatus.

Publisher Copyright:
© 2016 Elsevier Ltd.


  • Digital image correlation (DIC)
  • Discrete element method (DEM)
  • Material and structural length scales
  • Peak pressure
  • Size effect


Dive into the research topics of 'Fracture initiation in cavity expansion of rock'. Together they form a unique fingerprint.

Cite this