Engineering properties of concrete suitable for constructing physical barriers in radioactive waste disposal facilities

0506552 - ÚACH 2020 RIV BG eng C - Conference Paper (international conference)
Vejmelková, E. - Koťátková, J. - Bezdička, Petr - Konvalinka, P. - Černý, R.
Engineering properties of concrete suitable for constructing physical barriers in radioactive waste disposal facilities.
17th International Multidisciplinary Scientific GeoConference Surveying Geology and Mining Ecology Management, SGEM 2017. Sofia: STEF92 Technology, 2017, Roč. 17, č. 62 (2017), s. 147-154. ISBN 978-619-7408-13-3. ISSN 1314-2704.
[International Multidisciplinary Scientific GeoConference /17./ SGEM 2017. Albena (BG), 29.06.2017-05.07.2017]
R&D Projects: GA ČR(CZ) GA17-11635S
Institutional support: RVO:61388980
Keywords : Cement composites * Engineering properties * Pore size distribution * Radioactive waste disposal
OECD category: Inorganic and nuclear chemistry
https://www.sgem.org/index.php/elibrary?view=publication&task=show&id=4524

Several concrete mixtures suitable for constructing engineered barriers in radioactive waste disposal facilities are designed and tested. The mix design is based on the utilization of a natural sorbent acting, at the same time, as supplementary cementitious material replacing a part of Portland cement and fine filler capable of radionuclide absorption and fixing. A representative set of engineering properties of the hardened concrete mixes is determined, including the pore size distribution, bulk density, matrix density, open porosity, compressive strength, water absorption coefficient, and apparent moisture diffusivity. Experimental results show that an appropriate dosage of the natural sorbent in the analyzed concrete is within the range of 30-50% of the mass of Portland cement. This level of Portland cement replacement makes possible to utilize effectively the pozzolanic properties of the sorbent and still preserve its necessary amount in the non-hydrated state. The mechanical properties of concrete are then satisfactory for the supposed load, the water-penetration protection ability is sufficient, and the microcrystalline structure of non-hydrated sorbent can provide a sufficient interior pore surface area for fixing the anticipated radionuclide dose.
Permanent Link: http://hdl.handle.net/11104/0297784