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Gamma irradiation resistance of an early age slag-blended cement matrix for nuclear waste encapsulation

Published online by Cambridge University Press:  03 February 2015

Neda Mobasher
Affiliation:
Department of Materials Science & Engineering, Immobilisation Science Laboratory, The University of Sheffield, Sheffield S1 3JD, UK
Susan A. Bernal
Affiliation:
Department of Materials Science & Engineering, Immobilisation Science Laboratory, The University of Sheffield, Sheffield S1 3JD, UK
Hajime Kinoshita
Affiliation:
Department of Materials Science & Engineering, Immobilisation Science Laboratory, The University of Sheffield, Sheffield S1 3JD, UK
Clint A. Sharrad
Affiliation:
Research Centre for Radwaste and Decommissioning, Dalton Nuclear Institute, The University of Manchester, Manchester M13 9PL, UK
John L. Provis*
Affiliation:
Department of Materials Science & Engineering, Immobilisation Science Laboratory, The University of Sheffield, Sheffield S1 3JD, UK
*
a)Address all correspondence to this author. e-mail: [email protected]
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Abstract

Irradiation is one of the characteristic conditions that nuclear wasteforms must withstand to assure integrity during their service life. This study investigates gamma irradiation resistance of an early age slag cement-based grout, which is of interest for the nuclear industry as it is internationally used for encapsulation of low and intermediate level radioactive wastes. The slag cement-based grout withstands a gamma irradiation dose of 4.77 MGy over 256 h without reduction in its compressive strength; however, some cracking of irradiated samples was identified. The high strength retention is associated with the fact that the main hydration product forming in this binder, a calcium aluminum silicate hydrate (C–A–S–H) type gel, remains unmodified upon irradiation. Comparison with a heat-treated sample was carried out to identify potential effects of the temperature rise during irradiation exposure. The results suggested that formation of cracks is a combined effect of radiolysis and heating upon irradiation exposure.

Type
Articles
Copyright
Copyright © Materials Research Society 2014 

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Footnotes

Contributing Editor: William J. Weber

References

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