A thermo-hydro-mechanical stress-strain framework for modelling the performance of clay barriers in deep geological repositories for radioactive waste

Add to your list(s) Download to your calendar using vCal

• Prof. Lyesse Laloui, Swiss Federal Institute of Technology - EPFL
• Friday 06 November 2009, 16:30-17:30
• Engineering Department - LR6.

If you have a question about this talk, please contact Zelda Stuck.

Assessing the performance of deep geological repositories for heat-generating radioactive waste requires reliable predictions of the thermo-hydro-mechanical (THM) behaviour of the clay barriers (the buffer material as well as the host rock/clay). This represents an important element of the waste isolation system. In order to provide reasonable assurance that clay barriers will ensure nuclear waste isolation, it is essential to understand their behaviour under a variety of environmental conditions. The phenomena involved are complex, and adequately understanding the constitutive behaviour of clays and modelling their evolution is challenging. The stress-strain material behaviours that need to be understood and modelled include drying and wetting in non-isothermal conditions and heating-cooling in non-saturated conditions. Other aspects should be considered, such as drying induced cracks and the role of the material structure and its multi-porosity. The difficulty of some of these tasks is increased by the fact that some effects are coupled. The fundamental behaviours of clayey materials under the considered THM conditions are first identified and highlighted for deep repository experiments. We then propose a mechanical stress-strain constitutive framework to model the behaviour of clay barriers. This includes aspects such as the thermo-plastic behaviour of saturated and unsaturated materials. In the third part, we show that the proposed framework allows us to experimentally explain observed behaviours and to predict the THM behaviour of clay barriers.

This talk is part of the Engineering Department Geotechnical Research Seminars series.

This talk is included in these lists:

• Alex
• All Talks (aka the CURE list)
• Cambridge University Engineering Department Talks
• Cambridge talks
• Centre for Smart Infrastructure & Construction
• Civil Engineering Talks
• Computational Continuum Mechanics Group Seminars
• Engineering Department - LR6
• Engineering Department Geotechnical Research Seminars
• Featured lists
• Interested Talks
• School of Technology
• Trust & Technology Initiative - interesting events
• bld31

Note that ex-directory lists are not shown.