Progress in visualization of crack propagation in rocks using X-ray computed tomography

0494949 - ÚGN 2019 RIV JP eng C - Conference Paper (international conference)
Vavro, Leona - Vavro, Martin - Fíla, Tomáš - Kytýř, Daniel - Souček, Kamil
Progress in visualization of crack propagation in rocks using X-ray computed tomography.
Proceedings of the 39th West Japan Symposium on Rock Engineering. Nagasaki: Nagasaki University, 2018, s. 25-28. ISSN 0917-2580.
[West Japan Symposium on Rock Engineering /39./. Nagasaki (JP), 22.09.2018-23.09.2018]
R&D Projects: GA MŠMT(CZ) LO1406
Institutional support: RVO:68145535 ; RVO:68378297
Keywords : X-ray computed micro-tomography * non-homogeneous quasi-brittle materials * rocks
OECD category: Mechanical engineering; Materials engineering (UTAM-F)

High-resolution X-ray computed micro-tomography (CT) represents an effective tool for studying the processes of initiation, development and spreading of cracks in non-homogeneous quasi-brittle materials (e.g. rocks or concrete). This article presents recent progress focused on visualization of crack propagation in different rocks, especially sandstones. The CT visualization of crack propagation took place in three successive stages. In the first stage, an inspection of the final crack on disc-shaped bodies with a height of about 5 mm, cut from unbroken cylindrical samples after the chevron bend (CB) test was carried out. During the second phase, three-point bending CB tests were performed using an in-house designed loading device, allowing a precise control of the loading process based on modified LinuxCNC software (running on a real-time kernel). X-ray radiography of a horizontally oriented sample was carried out during loading. For the third, so far the last phase of the research, a completely newly designed loading device with four-point bending setup and vertically oriented scanned sample was used. This new design of the loading experiment, coupled with the high stiffness of the loading frame, makes it possible to interrupt the loading process at any time and perform CT scanning without the risk of sudden destruction of scanned sample.
Permanent Link: http://hdl.handle.net/11104/0288003