X-Ray CT inspection of subsurface areas of concretes exposed to fast flowing liquids

0533193 - ÚGN 2021 RIV CZ eng C - Conference Paper (international conference)
Sitek, Libor - Hlaváček, Petr - Souček, Kamil - Bodnárová, L. - Foldyna, Josef - Zajícová, Vendula - Berčáková, Andrea - Foldyna, Vladimír
X-Ray CT inspection of subsurface areas of concretes exposed to fast flowing liquids.
New trends in production engineering. Vol. 2. Warszawa: Sciendo, 2019 - (Kotwica, K.), s. 450-459. ISBN 978-3-11-067479-8. ISSN 2545-2843.
[International Conference “Mining Techniques” TUR 2019 /11./. Krynica (PL), 17.09.2019-20.09.2019]
R&D Projects: GA ČR GA18-25035S; GA MŠMT(CZ) LO1406
Institutional support: RVO:68145535
Keywords : erosion * concrete * fast flowing liquid * high-speed water jets * X-Ray CT
OECD category: Civil engineering
https://content.sciendo.com/view/journals/ntpe/2/1/article-p450.xml?product=sciendo

Concrete structures affected for a long time by flowing liquids are exposed to gradual erosion in surface layers caused by a combination of several degradation processes: abrasion, cavitation and chemical or bacterial impacts. Due to the complex phenomena and difficult-to-define initial and boundary conditions, the whole process cannot be easily simulated using the conventional computing tools. Laboratory experimental research is thus the most appropriate approach for the investigation of a suitable composition of concrete resistant to the flowing liquids. However, the methods used are often very time consuming and last even several years. High-speed water flows can be elegantly used for the acceleration of the mechanical simulation of a real situation. Several experiments on the effects of the high-speed water flows on concrete surfaces have been carried out. Using the X-Ray CT methods, subsurface structures of concretes exposed to the accelerated mechanical simulation of the erosion wear caused by fast flowing liquids were investigated and presented in the article. It has been shown that the simulation does not cause initiation of new fractures or cracks in the original concrete structure. The pure water flow mainly removes the hardened cement paste and reveals the aggregate grains. The water flow with abrasive particles disintegrates in greater depths and washes out entire aggregate grains, eventually amputates them and finally smoothens entire surface.
Permanent Link: http://hdl.handle.net/11104/0311661