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Chemistry and Performance of Blended Cements and Backfills for use in Radioactive Waste Disposal

Published online by Cambridge University Press:  03 September 2012

S. Duerden ,
F. P. Glasser ,
K. Goldthorpe ,
J. Pedersen ,
K. Quillin ,
D. Ross ,
S. A. Stronach  and
M. Tyrer
S. Duerden
Affiliation:
Environmental Agency, 2 Marsham Street, London, SW1P 3EB
F. P. Glasser
Affiliation:
Department of Chemistry, University of Aberdeen, Old Aberdeen, AB24 3UE, Scotland.
K. Goldthorpe
Affiliation:
Department of Chemistry, University of Aberdeen, Old Aberdeen, AB24 3UE, Scotland.
J. Pedersen
Affiliation:
Department of Chemistry, University of Aberdeen, Old Aberdeen, AB24 3UE, Scotland.
K. Quillin
Affiliation:
Building Research Establishment, Garston, Watford, WD2 7JR, England.
D. Ross
Affiliation:
W.S. Atkins, Epsom, Surrey, England.
S. A. Stronach
Affiliation:
Department of Chemistry, University of Aberdeen, Old Aberdeen, AB24 3UE, Scotland.
M. Tyrer
Affiliation:
Imperial College of Science, Technology and Medicine, London, SW7 2BP, England.
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Abstract

The ability of NaCl and MgSO4 to impair the performance of Portland cement, blended cements containing slag and fly ash and of a permeable backfill have been measured. Performance is determined by decrease in pH, changes in mineralogy and loss of physical coherence. Experiments have been made at 25°, 55° and 85°C and extensively backed up by chemical models of cement performance. NaCl, up to 1.5M, has a comparatively slight impact on performance but MgSO4 rapidly and almost quantitatively reacts, lowering system pH's to < 10, conditioned by mixtures of Mg(OH)2 and magnesium silicates with gypsum.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 465: Symposium II – Scienfific Basis for Nuclear Waste Management XX , 1996 , 287
Copyright
Copyright © Materials Research Society 1997

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References

REFERENCES

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