Hostname: page-component-586b7cd67f-2brh9 Total loading time: 0 Render date: 2024-11-26T13:57:15.042Z Has data issue: false hasContentIssue false
  • English
  • Français

Earthquake-induced rock shear through a deposition hole: Laboratory tests on bentonite-material models and modelling of three scale tests

Published online by Cambridge University Press:  22 June 2018

Lennart Börgesson ,
Ann Dueck  and
Jan Hernelind
Lennart Börgesson
Affiliation:
Clay Technology AB, IDEON Science Park, SE-223 70 Lund, Sweden
Ann Dueck*
Affiliation:
Clay Technology AB, IDEON Science Park, SE-223 70 Lund, Sweden
Jan Hernelind
Affiliation:
5T Engineering AB, Fornforskargatan 86, SE-723 53 Västerås, Sweden
*
*E-mail address of corresponding author: [email protected]
Get access Rights & Permissions [Opens in a new window]

Abstract

Earthquake-induced rock shear through a bentonite-filled deposition hole in a repository for spent nuclear fuel is an important scenario for the safety analysis because it may cause substantial damage to the canister hosting the spent fuel. Appropriate tools to investigate the effects on the buffer and the canister are required.

The study described here explored the laboratory tests conducted to develop a material model of the bentonite buffer to be used in the simulations, the material models that these tests have provided and finite element (FE) simulations of three scale tests of a rock shear for comparison between modelled and measured results. The results were used for validation of the material models and the calculation technique that was used for modelling different rock-shear cases.

The laboratory study consisted of swelling-pressure tests and tests to determine shear strength and stress-strain properties. The material model is elastic-plastic with a nonlinear stress-strain relation which depends on the density of the bentonite buffer and is a function of the strain rate. The three scale tests were modelled using the Abaqus finite element code. Good agreement between modelled and measured results was observed, in spite of the complexity of the models and the difficulties associated with measuring stresses and strains under the very fast shear.

The modelling results thus validate the modelling of the SR-Site. The modelling technique, the element mesh and the material models used in these analyses are well fitted and useful for this type of modelling.

Keywords

stressstrainshearAbaqus finite element codefinite element modellingnuclear fuel disposal
Type
Article
Information
Clay Minerals , Volume 53 , Issue 2 , June 2018 , pp. 213 - 235
Copyright
Copyright © Mineralogical Society of Great Britain and Ireland 2018 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Footnotes

Associate Editor: S. Kaufhold

This paper was presented during the session: ‘ES-04: Clay barriers performance in the long-term isolation of waste’ of the International Clay Conference, 2017.

References

REFERENCES

Åkesson, M., Olsson, S., Dueck, A., Nilsson, U., Karnland, O., Kiviranta, L., Kumpulainen, S. & Lindén, J. (2012) Temperature buffer test. Hydro-mechanical and chemical/mineralogical characterizations. SKB Report P-12-06. Svensk Kärnbränslehantering AB.Google Scholar
Börgesson, L. (1986) Model shear tests of canisters with smectite clay envelopes in deposition holes. SKB Technical Report 86-26. Svensk Kärnbränslehantering AB.Google Scholar
Börgesson, L. & Hernelind, J. (2010) Earthquake induced rock shear through a deposition hole – modeling of three model tests scaled 1:10. Verification of the bentonite material model and the calculation technique. SKB TR-10-33. Svensk Kärnbränslehantering AB.Google Scholar
Börgesson, L., Hökmark, H. & Karnland, O. (1988) Rheological properties of sodium smectite clay. SKB Technical Report TR-88-30. Svensk Kärnbränslehantering AB.Google Scholar
Börgesson, L., Johannesson, L-E., Sandén, T. & Hernelind, J. (1995) Modelling of the physical behaviour of water saturated clay barriers. Laboratory tests, material models and finite element application. SKB Technical Report TR-95-20. Svensk Kärnbränslehantering AB.Google Scholar
Börgesson, L., Johannesson, L.-E. & Hernelind, J. (2004) Earthquake induced rock shear through a deposition hole. Effects on the canister and the buffer. SKB Technical Report TR-04-02. Svensk Kärnbränslehantering AB.Google Scholar
Börgesson, L., Dueck, A. & Johannesson, L.-E. (2010) Material model for shear of the buffer – evaluation of laboratory test results. SKB TR-10-31. Svensk Kärnbränslehantering AB.Google Scholar
Di Maio, C. & Fenelli, G.B. (1994) Residual strength of kaolin and bentonite: the influence of their constituent pore fluid. Géotechnique, 44(4), 217–226.Google Scholar
Dixon, D.A., Kohle, C.L., Drew, D. & Keith, S.G. (2006) Tensile and unconfined compression properties of highly compacted bentonite, bentonite-sand-buffer, dense and light backfill. Ontario Power Generation, Nuclear Waste Management Division Report No. 06819-REP-01300-10118-R00, Supporting Technical Report.Google Scholar
Dueck, A. (2010) Thermo-mechanical cementation effects in bentonite investigated by unconfined compression tests. SKB Technical Report TR-10-41. Svensk Kärnbränslehantering AB.Google Scholar
Dueck, A., Börgesson, L. & Johannesson, L.-E. (2010) Stress-strain relation of bentonite at undrained shear – laboratory tests to investigate the influence of material composition and test technique. SKB Technical Report TR-10-32. Svensk Kärnbränslehantering AB.Google Scholar
Dueck, A., Johannesson, L.-E., Kristensson, O., Olsson, S. & Sjöland, A. (2011) Hydro-mechanical and chemical-mineralogical analyses of the bentonite buffer from a full-scale field experiment simulating a high-level waste repository. Clay and Clay Minerals, 59, 595–607.Google Scholar
ENRESA (1998) FEBEX Full scale engineered barriers experiment in crystalline host rock. Pre-operational stage. Summary report. ENRESA Publication Tecnica Num. 01/98.Google Scholar
Fredlund, D.G. & Rahardjo, H. (1993) Soil Mechanics for Unsaturated Soils. John Wiley & Sons Inc.Google Scholar
Graham, J., Oswell, J.M. & Gray, M.N., (1992) The effective stress concept in saturated sand-clay buffer. Canadian Geotechnical Journal, 29, 1033–1043.Google Scholar
Harrington, J.F. & Birchall, D.J. (2007) Sensitivity of total stress to changes in externally applied water pressure in KBS-3 buffer bentonite. SKB Technical Report TR-06-38. Svensk Kärnbränslehantering AB.Google Scholar
Hernelind, J. (2010) Modelling and analysis of canister and buffer for earthquake induced rock shear and glacial loads. SKB Technical Report TR-10-34. Svensk Kärnbränslehantering AB.Google Scholar
Kahr, G., Kraehenbuehl, F., Stoeckli, H.F. & Müller-Vonmoos, M. (1990) Study of the water-bentonite system by vapour adsorption, immersion calorimetry and X-ray techniques: II. Heats of immersion, swelling pressure and thermodynamic properties. Clay Minerals, 25, 499–506.Google Scholar
Karnland, O., Sandén, T., Johannesson, L.-E., Eriksen, T.E., Jansson, M., Wold, S., Pedersen, K., Motamedi, M. & Rosborg, B. (2000) Long term test of buffer material. Final report on the pilot parcels. SKB Technical Report TR-00-22. Svensk Kärnbränslehantering AB.Google Scholar
Karnland, O., Muurinen, A. & Karlsson, F. (2005) Bentonite swelling pressure in NaCl solutions – Experimentally determined data and model calculations. Proceedings of the International Symposium on Large-Scale Field Tests in Granite, Spain 2003. Advances in Understanding Engineered Clay Barriers (Alonso, E.E. and Ledesma, A., editors), pp. 241–256.Google Scholar
Karnland, O., Olsson, S. & Nilsson, U. (2006) Mineralogy and sealing properties of various bentonites and smectite-rich clay materials. SKB Technical Reports TR-06-30. Svenska Kärnbränslehantering AB.Google Scholar
Karnland, O., Nilsson, U., Weber, H. & Wersin, P. (2008) Sealing ability of Wyoming bentonite pellets foreseen as buffer material – Laboratory results. Physics and Chemistry of the Earth, 33, 472–475.Google Scholar
Karnland, O., Olsson, S., Dueck, A., Birgersson, M., Nilsson, U., Hernan-Håkansson, T., Pedersen, K., Nilsson, S., Eriksen, T. & Rosborg, B. (2009) Long term test of buffer material at the Äspö Hard Rock Laboratory, LOT project. Final report on the A2 parcel. SKB Technical Report TR-09-29. Svensk Kärnbränslehantering AB.Google Scholar
Man, A. & Martino, J.B. (2009) Thermal, Hydraulic and Mechanical Properties of Sealing Materials. NWMO TR-2009-20. Nuclear Waste Management Organization, Canada.Google Scholar
Supplementary material: File

Börgesson et al. supplementary material

Figures S1-S2

Download Börgesson et al. supplementary material(File)
File 819.7 KB