Solid body fracturing mode by shear-tensile source model: acoustic emission laboratory study

01.01.2016 - 31.12.2018
Grant agency: 
Registration number: 
Internal investigator/coinvestigator: 
Tomáš Lokajíček
Interní řešitel: 
is principal investigator
External investigator/coinvestigator: 
Jan Šílený (Institute of Geophysics of the CAS, v. v. i.)

Acoustic emission (AE) is the process accompanying the brittle fracturing of solid body and simultaneously an indispensable tool for its study. Laboratory experiments under controlled loading conditions make it possible to differentiate the effect of important factors like material structure, stress field, crack presence, etc. on fracture initiation and development, and allow simulate the nature in situ. We will detect and classify the shear and tensile modes of rock fracturing by inverting the AE data gathered using a multichannel AE event recording system. The goal is to reveal mutual influence of rock structure and stress orientation, as well as the impact of microcrack concentration and orientation on the fracture mode changes. A novel source model consisting straight from the individual fracture modes will be applied for inversion of AE data, which is more robust in contrast to the traditional moment tensor against common deficiencies in the setup of the inverse task, like noise in the data, mislocation, inexact velocity model and sparse configuration of the sensors.