Peter the Great St. Petersburg Polytechnic University (St. Petersburg, Russia):
Buldakov P. Yu., Postgraduate, pavelbuldakov_teormech@mail.ru

Krivtsov A. M., Head of Laboratory, Doctor of Physical and Mathematical Sciences, Associate Professor, akrivtsov@bk.ru

Petrozavodsk State University (Petrozavodsk, Russia):
Kameneva E. E., Head of Laboratory, Candidate of Engineering Sciences, Senior Researcher, elena.kameneva@mail.ru

Institute for Problems in Mechanical Engineering of RAS (IPME RAS) (St. Petersburg, Russia):
Kuzkin V. A., Senior Researcher, Candidate of Physical and Mathematical Sciences, Associate Professor, kuzkinva@gmail.com

The paper proposes a methodology for processing X-ray computer microtomography data using non-commercial software packages to obtain input data for modeling deformation and fracture of rocks. Microtomographic images processing allows establishing the sizes, shapes, and spatial orientations of voids (pores, microcracks, pore channels). Based on the analysis of non-commercial packages specializing in tomographic image processing, CTan Demo and In-Vesalius packages were selected. When analyzing images using the CTan Demo software package, information is obtained on voxel sizes and void boundaries. This information is transmitted to the InVesalius program, where it is used to create a voxel model of all voids for the sample studied. The voxel model is then converted to a format used by CAD editors (e. g. STL). An example application for the method proposed is presented in the form of the results of microtomographic images processing for microcline-plagioclase granite samples obtained using a SkyScan-1172 microtomograph with the resolution of 0.5 to 15 μm. The spatial distribution, orientation, and shapes of the voids inside the sample are established. The sphericity coefficients are calculated for the voids. An analysis of the tomographic images in a 3D system revealed typical cavity shapes in the rock volume. The results presented may be used to develop deformation and fracture models for rocks under various loading conditions.
The work was carried out with the support of the Russian Science Foundation (grant No.17-79-30056).

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