Novel device for 4-point flexural testing of quasi-brittle materials during 4D computed tomography

0490614 - ÚTAM 2019 RIV CH eng C - Konferenční příspěvek (zahraniční konf.)
Koudelka_ml., Petr - Fíla, Tomáš - Kytýř, Daniel - Vavro, Leona - Vavro, Martin - Souček, Kamil - Vavřík, Daniel - Drdácký, Miloš
Novel device for 4-point flexural testing of quasi-brittle materials during 4D computed tomography.
Proceedings of the first International conference on theoretical, applied and experimental mechanics. Cham: Springer, 2018 - (Gdoutos, E.), s. 27-32. Structural integrity, 5. ISBN 978-3-319-91988-1. ISSN 2522-560X.
[International conference on theoretical, applied and experimental mechanics /1./. Paphos (CY), 17.06.2018-20.06.2018]
Grant CEP: GA ČR(CZ) GBP105/12/G059
Institucionální podpora: RVO:68378297 ; RVO:68145535
Klíčová slova: four-point bending * fracture process zone * 4D micro-CT
Obor OECD: Applied mechanics; Applied mechanics (UGN-S)
https://doi.org/10.1007/978-3-319-91989-8_5

This paper deals with development and validation of a novel device for investigation of the crack behavior in quasi-brittle materials using radiographically observed flexural testing. Instead of standard horizontal arrangement of three-point bending devices, a novel approach consisting in a vertically oriented four-point bending setup is proposed. In the paper, technical description of the proposed device together with its advantages over existing methods and results of validation experiments with natural rocks are presented. The validation experiments were concentrated on the ability of the device to capture the fracture behavior of the samples using X-ray transmission radiography and 4D X-ray micro-tomography. Particular attention was paid to evaluate the ability to perform tomographic scans during post-peak softening, i.e. on intermittent loading of samples after formation of the crack. The acquired results showed very good performance in terms of both the mechanical characteristics of the device (stiffness and loading precision) and the X-ray imaging properties.
Trvalý link: http://hdl.handle.net/11104/0284789