Coupled thermo-hydro-mechanical processes in the near field of a high-level radioactive waste repository in clay formations

The present paper provides an overview of key coupled thermo-hydro-mechanical (THM) processes in clay formations that would result from the development of a high-level radioactive waste repository. Here, in this paper, clay formations include plastic clay such as the Boom Clay of Belgium, as well as more indurated clay such as the Callovo-Oxfordian and Upper Toarcian of France and Opalinus Clay of Switzerland. First, we briefly introduce and describe four major Underground Research Laboratories (URLs) that have been devoted to clay repository research over the last few decades. Much of the research results in this area have been gained through investigations in these URLs and their supporting laboratory and modeling research activities. Then, the basic elements in the development of a waste repository in clays are presented in terms of four distinct stages in repository development. For each of these four stages, key processes and outstanding issues are discussed. A summary of the important areas of research needs and some general remarks then conclude this paper.

[1]  Claudio Scavia,et al.  Fractures and Self-healing within the Excavation Disturbed Zone in Clays ( SELFRAC ) Final report , 2007 .

[2]  K. Lux,et al.  Physical modelling and numerical simulation of long-term deformation behaviour of indurated clay with special consideration of anisotropic effects and in situ measurements , 2006 .

[3]  R. Charlier,et al.  EDZ in clayey rocks: wich effect on permeability? , 2009 .

[4]  Y. Cui,et al.  Investigating the time-dependent behaviour of Boom clay under thermomechanical loading , 2009, 0904.3652.

[5]  Chun-liang Zhang,et al.  Damage and sealing of clay rocks detected by measurements of gas permeability , 2008 .

[6]  C. Tsang,et al.  Geohydromechanical Processes in the Excavation Damaged Zone in Crystalline Rock, Rock Salt, and Indurated and Plastic Clays , 2004 .

[7]  Robert Charlier,et al.  Thermo-hydro-mechanical coupling in clay barriers , 2002, Poromechanics.

[8]  R. Charlier,et al.  Damage around tunnels in indurated clay: hydro-mechanical modelling aspects , 2009 .

[9]  J. D. Barnichon,et al.  The SEALEX In Situ Experiments: Performance Tests Of Repository Seals , 2011 .

[10]  Numerical post failure methods in multiphysical problems , 2009 .

[11]  Antonio Gens,et al.  In situ behaviour of a stiff layered clay subject to thermal loading : observations and interpretation , 2007 .

[12]  Yu-Jun Cui,et al.  Suction effects in deep Boom Clay block samples , 2007 .

[13]  V. Labiouse,et al.  Self-Sealing of Localised Cracks in Boom and Opalinus Clay Hollow Cylinders , 2012 .

[14]  H. Shao,et al.  Hydro-Mechanical Evolution of Damaged Zones around a Microtunnel in a Claystone Formation of the Swiss Jura Mountains , 2008 .

[15]  X. L. Li,et al.  An overview of long-term HM measurements around HADES URF , 2006 .

[16]  S. Savoye,et al.  In-situ diffusion of HTO, 22Na+, Cs+ and I- in Opalinus Clay at the Mont Terri underground rock laboratory , 2004 .

[17]  A. Rejeb.  Time-dependent Behaviour of Tournemire Argillites (France) , 2003 .

[18]  Jean-Bernard Kazmierczak,et al.  RHEOLOGICAL CHARACTERIZATION OF A CLAY FORMATION FROM DRIFTS EXCAVATION : ELASTIC AND ELASTOPLASTIC APPROACH , 2006 .

[19]  Daniel Grolimund,et al.  Diffusion of HTO, Br−, I−, Cs+, 85Sr2+ and 60Co2+ in a clay formation: Results and modelling from an in situ experiment in Opalinus Clay , 2008 .

[20]  M. Mazurek,et al.  FEPCAT Project: Features, Events and Processes Evaluation Catalogue for Argillaceous Media , 2003 .

[21]  Nabil Sultan,et al.  Permeability changes in Boom clay with temperature , 2009, 1112.6396.

[22]  N. Hoteit,et al.  Under stress permeability determination of the Meuse/Haute-Marne mudstone , 2005 .

[23]  J. Maßmann,et al.  Investigation of desaturation in an old tunnel and new galleries at an argillaceous site , 2009 .

[24]  F. Bernier,et al.  Similarities in the hydromechanical response of Callovo-Oxfordian clay and Boom Clay during gallery excavation , 2008 .

[25]  Paul Bossart,et al.  Geological and hydraulic characterisation of the excavation disturbed zone in the Opalinus Clay of the Mont Terri Rock Laboratory , 2002 .

[26]  W. Bastiaens,et al.  Twenty-five years' geotechnical observation and testing in the Tertiary Boom Clay formation , 2007 .

[27]  Paul Marschall,et al.  Characterisation of Gas Transport Properties of the Opalinus Clay, a Potential Host Rock Formation for Radioactive Waste Disposal , 2005 .

[28]  Justo Cabrera,et al.  Desaturation and structure relationships around drifts excavated in the well-compacted Tournemire's argillite (Aveyron, France) , 2007 .

[29]  Patrick Lebon,et al.  The excavation damaged zone in clay formations time-dependent behaviour and influence on performance assessment , 2007 .

[30]  Paul Bossart,et al.  Structural and hydrogeological characterisation of the excavation-disturbed zone in the Opalinus Clay (Mont Terri Project, Switzerland) , 2004 .

[31]  Time-dependent evolution of the excavation damaged zone in the argillaceous Tournemire site , 2006 .

[32]  J. Maßmann,et al.  Study of the initiation and propagation of excavation damaged zones around openings in argillaceous rock , 2009 .

[33]  Yu-Jun Cui,et al.  Thermo-mechanical behaviour of a compacted swelling clay , 2008, 0802.1433.

[34]  A. G. Corkum,et al.  Modelling a mine-by test at the Mont Terri rock laboratory, Switzerland , 2007 .

[35]  Gilles Armand,et al.  Making of the underground scientific experimental programme at the Meuse/Haute-Marne underground research laboratory, North Eastern France , 2007 .

[36]  Robert Charlier,et al.  Hydro-mechanical modelling of the excavation damaged zone around an underground excavation at Mont Terri Rock Laboratory , 2010 .

[37]  T. Popp,et al.  Anisotropy of seismic and mechanical properties of Opalinus clay during triaxial deformation in a multi-anvil apparatus , 2007 .

[38]  Patrick Landais,et al.  Clays in Natural and Engineered Barriers for Radioactive Waste Confinement , 2007 .

[39]  P. Marschall,et al.  Hydromechanical Evolution and Self-Sealing of Damage Zones around a Microtunnel in a Claystone Formation of the Swiss Jura Mountains , 2009 .

[40]  Patrick Landais,et al.  Clays in natural and engineered barriers for radioactive waste confinement , 2004 .

[41]  W Bastiaens,et al.  Characterisation of induced discontinuities in the Boom Clay around the underground excavations (URF, Mol, Belgium) , 2004 .

[42]  G. Armand,et al.  Failure mechanisms of the Opalinus Clay around underground excavations , 2006 .

[43]  Antonio Gens Solé,et al.  Comparative study of three in-situ heating test of anisotropic media: the HE-D, TER and ATLAS experiments , 2009 .

[44]  Y. Cui,et al.  Yielding and plastic behaviour of an unsaturated compacted silt , 1996 .

[45]  P. Marschall,et al.  Creation and Evolution of Damage Zones Around a Microtunnel in a Claystone Formation of the Swiss Jura Mountains , 2006 .

[46]  V. Labiouse,et al.  Laboratory and in Situ Simulation Tests of the Fracturing in the EDZ around Galleries in Opalinus Clay , 2012 .

[47]  Y. Cui,et al.  Temperature effects on the volume change behaviour of Boom clay , 2002 .

[48]  E. Frank,et al.  INFLUENCE OF BEDDING PLANES TO EDZ-EVOLUTION AND THE COUPLED HM PROPERTIES OF OPALINUS CLAY , 2007 .

[49]  J. García-Siñeriz,et al.  Ventilation experiment in the Mont Terri underground laboratory , 2007 .

[50]  M. Naumann,et al.  Experimental investigations on anisotropy in dilatancy, failure and creep of Opalinus Clay , 2007 .