Fernández A.M., Melón A, Sánchez M.D, Gaucher E., Tournassat C., Altmann S., Vinsot A., Maes N., de Craen M., Leupin O., Wersin P., Astudillo J. 2009. Study of different argillaceous formations performed in the context of the Funmig Project. Publicación Técnica ENRESA ISSN: 1134-380X, Vol. 05/2009, 1-214.

Van Geet, M.; Bastiaens, W.; Volckaert, G.; Weetjens, E.; Sillen, X.; Maes, N.; Imbert, C.; Billaud, P.; Touzé, G.; Filippi, M.; Plas, F.; Villar, M.V.; García-Gutiérrez, M.; Mingarro, M.; Gens, A. & Vallejan, B. 2009. RESEAL II. A large-scale in situ demonstration test for repository sealing in an argillaceous host rock - Phase II. Final report. EUR 24161, Nuclear Science and Technology. European Commission, Luxembourg, 288 pp. ISBN 978-92-79-13626-9.

Villar, M.V.; Fernández, A.M.; Martín, P.L.; Barcala, J.M.; Gómez-Espina, R. & Rivas, P. 2008. Effect of heating/hydration on compacted bentonite: tests in 60-cm long cells. Colección Documentos CIEMAT. CIEMAT, Madrid. 72 pp. ISBN 978-84-7834-597-4.

Huertas, F.; Fariña, P.; Farias, J.; García-Siñeriz, J.L.; Villar, M.V.; Fernández, A.M.; Martín, P.L.; Elorza, F.J.; Gens, A.; Sánchez, M.; Lloret, A.; Samper, J. & Martínez, M.A. 2006. Full-scale Engineered Barriers Experiment. Updated Final Report 1994-2004. Publicación Técnica ENRESA 05-0/2006. ENRESA, Madrid. 590 pp. ISSN 1134-380X.

Villar, M.V. (ed.) 2006. FEBEX Project Final report. Post-mortem bentonite analysis. Publicación Técnica ENRESA 05-1/2006. ENRESA, Madrid. 183 pp. ISSN 1134-380X.

Lloret, A., Romero, E. & Villar, M.V. 2004. FEBEX II Project. Final report on thermo-hydro-mechanical laboratory tests. Publicación Técnica ENRESA 10/2004. ENRESA, Madrid. 165 pp. ISSN 1134-380X.

Villar, M.V. 2002. Thermo-hydro-mechanical characterisation of a bentonite from Cabo de Gata. A study applied to the use of bentonite as sealing material in high level radioactive waste repositories. Publicación Técnica ENRESA 01/2002. 258 pp. Madrid.

AITEMIN, ANDRA, CIEMAT, CSIC-Zaidín, G.3S, GRS, NAGRA, SGS Tecnos SA, ULC, UPC-DIT, UPM. 2000. Full-scale engineered barriers experiment for a deep geological repository for high level radioactive waste in crystalline host rock (FEBEX Project). Final Report. EUR 19147. Commission of the European Communities, Luxemburgo. 362 pp. ISBN 92-828-9285-9.

Volckaert, G.; Dereeper, B.; Put, M.; Ortiz, L.; Gens, A.; Vaunat, J.; Villar, M.V.; Martín, P.L.; Imbert, C.; Lassabatère, T.; Mouche, E. & Cany, F. 2000. A large-scale in situ demonstration test for repository sealing in an argillaceous host rock. Reseal project – Phase I. EUR 19612. Commission of the European Communities, Luxemburgo. 273 pp. ISBN 92-894-0095-1.

Villar, M.V., Martín, P.L., Pelayo, M., Ruiz, B., Rivas, P., Alonso, E., Lloret, A., Pintado, X., Gens, A., Linares, J., Huertas, F., Caballero, E., Jiménez de Cisneros, C., Obis, J. Pérez, A., Velasco, V. 1998. FEBEX. Bentonita: origen, propiedades y fabricación de bloques. Publicación Técnica ENRESA 04/98. ENRESA, Madrid. 146 pp. ISSN 1134-380X.

Villar, M.V., Martín, P.L., Pelayo, M., Ruiz, B., Rivas, P., Alonso, E., Lloret, A., Pintado, X., Gens, A., Linares, J., Huertas, F., Caballero, E., Jiménez de Cisneros, C., Obis, J. Pérez, A., Velasco, V. 1998. FEBEX. Bentonite: origin, properties and fabrication of blocks. Publicación Técnica ENRESA 05/98. ENRESA, Madrid. 146 pp. ISSN 1134-380X.

Volckaert, G.; Bernier, F.; Alonso, E.; Gens, A.; Samper, J.; Villar, M.V.; Martín, P.L.; Cuevas, J.; Campos, R.; Thomas, H.R.; Imbert, C. & Zingarelli, V. 1996. Thermal-hydraulic-mechanical and geochemical behaviour of the clay barrier in radioactive waste repositories (model development and validation). Nuclear science and technology. EUR 16744. Commission of the European Communities, Luxemburgo. 722 pp. ISBN 92-827-5743-9.

Villar, M.V. 1995. Thermo-hydro-mechanical characterization of the Spanish reference clay material for engineered barrier for granite and clay HLW repository: laboratory and small mock-up testing. Publicación Técnica ENRESA 03/95. ENRESA, Madrid. 251 pp. ISSN 1134-380X.

Villar M.V., Gutiérrez-Ávarez, C., Martín P.L., 2020. Low-suction water retention capacity of bentonite at high temperature. E-UNSAT 2020. E3S Web of Conferences 195, 04010 (2020). DOI: https://doi.org/10.1051/e3sconf/202019504010.

Villar M.V., Romero F.J., Martín P.L., Gutiérrez-Rodrigo V., Barcala J.M. 2019. Experimental Investigation of Gas Transport in the Shaly Facies of Opalinus Clay. In: Ferrari A., Laloui L. (eds): Energy Geotechnics. SEG 2018. Springer Series in Geomechanics and Geoengineering.  434-441. Springer, Cham. 978-3-319-99669-1. 

Villar, M.V. & Lloret, A. 2018. Bentonite strain due to cyclic suction changes. In: Ng, C.W.W., Leung, A.K., Chiu, A.C.F., Zhou, C. (Eds): Unsaturated soils. The 7th International Conference on Unsaturated Soils 2018 (UNSAT2018). Hong Kong University of Science and Technology, Hong Kong. Vol. 1: 557-562. ISBN: 978-988-14032-2-3.

Gens, A., Pomaro, B., Sánchez, M., Villar, M.V. 2018. On the hydration of unsaturated barriers for high-level nuclear waste disposal. In: Ng, C.W.W., Leung, A.K., Chiu, A.C.F., Zhou, C. (Eds): Unsaturated soils. The 7th International Conference on Unsaturated Soils 2018 (UNSAT2018). Hong Kong University of Science and Technology, Hong Kong. Vol. 1: 55-60. ISBN: 978-988-14032-2-3.

Villar, M.V.; Iglesias, R.J.; Gutiérrez, C. & Campos, G. 2017. Use of psychrometers, capacitive sensors and vapour transfer technique to determine the water retention curve of compacted bentonite. In: Ferrari, A. & Laloui, L. (Eds.) Advances in Laboratory Testing and Modelling of Soils and Shales (ATMSS). Springer Series in Geomechanics and Geoengineering, pp 123-130. Springer, Cham, Switzerland. ISBN 978-3-319-52772-7. DOI: https://doi.org/10.1007/978-3-319-52773-4_13.

Villar, M.V., Gutiérrez-Rodrigo, V., Iglesias, R.J., Campos, R., Gutiérrez-Nebot. L. 2016. Changes on the microstructure of compacted bentonite caused by heating and hydration. 3RD European Conference On Unsaturated Soils - E-UNSAT 2016. E3S Web of Conferences 9, 18001 (2016). DOI: https://doi.org/10.1051/e3sconf/20160918001.

Villar, M.V., Martín, P.L., Romero, F.J., Gutiérrez-Rodrigo, V., Barcala, J.M. 2015. Gas and water permeability of concrete. In: Shaw, R. P. (ed.) Gas Generation and Migration in Deep Geological Radioactive Waste Repositories. Geological Society, London, Special Publications, 415, 59-73. First published online November 14, 2014. http://dx.doi.org/10.1144/SP415.4.

Gutiérrez-Rodrigo, V., Villar, M.V., Martín, P.L., Romero, F.J., Barcala, J.M. 2015. Gas-breakthrough pressure of FEBEX bentonite. In: Shaw, R. P. (ed.) Gas Generation and Migration in Deep Geological Radioactive Waste Repositories. Geological Society, London, Special Publications, 415, 47-57. First published online November 14, 2014. http://dx.doi.org/10.1144/SP415.4. 

Gutiérrez-Rodrigo, V., Villar, M.V., Martín, P.L. & Romero, F.J. 2014: Gas transport properties of compacted bentonite. In: Khalili, N., Russell, A., Khoshghalb, A. (Eds.): Unsaturated Soils: Research and Applications, vol. 2: 1735-1740. Taylor & Francis Group, London. ISBN: 978-1-138-00150-3. 

Villar, M.V., Gómez-Espina, R., Campos, R., Gutiérrez-Nebot, L. & Barrios, I. 2014. Retention curves of bentonite under a microstructural perspective. In: Khalili, N., Russell, A., Khoshghalb, A. (Eds.): Unsaturated Soils: Research and Applications, vol. 2: 989-994. Taylor & Francis Group, London. ISBN: 978-1-138-00150-3.

Martín, P.L., Barcala, J.M. & Villar, M.V. 2014. Behaviour of a bentonite barrier under thermal and hydraulic gradients: FEBEX mock-up test, 16 years of operation. In: Khalili, N., Russell, A., Khoshghalb, A. (Eds.): Unsaturated Soils: Research and Applications, vol. 1: 857-862. Taylor & Francis Group, London. ISBN: 978-1-138-00150-3.

Villar, M.V.; Gómez-Espina, R.; Martín, P.L. & Barcala, J.M. 2012. Tests in thermo-hydraulic cells to simulate the behaviour of engineered barriers. In: Laloui, L. & Ferrari, A. (Eds.): Multiphysical Testing of Rocks and Shales. Springer Series in Geomechanics and Geoengineering, pp. 137-142. Springer, Berlin. ISBN: 978-3-642-32491-8.

Villar, M.V.; Gómez-Espina, R.; Campos, R.; Barrios, I. & Gutiérrez-Nebot, L. 2012. Porosity Changes Due To Hydration Of Compacted Bentonite. In: Mancuso, C.; Jommi, C. & D'Onza, F. (Eds.): Unsaturated Soils: Research and Applications, Volume 1, pp. 137-144. Springer, Berlin. ISBN: 978-3-642-31115-4.

Villar, M.V.; Martín, P.L.; Romero, F.J., Barcala, J.M. & Gutiérrez-Rodrigo, V. 2012. Gas transport through bentonite: influence of dry density, water content and boundary conditions. In: Skoczylas, F.; Davy, C.A.; Agostini, F. & Burlion, N. (eds.): Propiétés de Transfert des Géomatériaux. Transfert 2012, Actes du Colloque: 379-389.

Jacinto, A.; Villar, M.V.; Gómez-Espina, R. & Ledesma, A. 2011. Influence of temperature on the water retention capacity of soils. Analysis using solution thermodynamics. In: Alonso, E.E. & Gens, A. (eds.): Unsaturated Soils. CRC Press/Balkema Proceedings and Monographs in Engineering, Water and Earth Sciences. Taylor & Francis Group, London. pp 555-560.

M.V. Villar, P.L. Martín, R. Gómez-Espina & A. Lloret. 2011. Effect of suction and plasticity on the shear strength of sand/silt mixtures. In: Alonso, E.E. & Gens, A. (eds.): Unsaturated Soils. CRC Press/Balkema Proceedings and Monographs in Engineering, Water and Earth Sciences. Taylor & Francis Group, London. pp 391-396.

Sánchez, M; Villar, M.V.; Lloret, A. & Gens, A. 2011. Evolution of swelling pressure in compacted bentonite: experiments and modelling. In: Alonso, E.E. & Gens, A. (eds.): Unsaturated Soils. CRC Press/Balkema Proceedings and Monographs in Engineering, Water and Earth Sciences. Taylor & Francis Group, London. pp 359-364.

Sánchez, M.; Gens, A.; Villar, M.V. & Lloret, A. 2010. Simulation of expansive clay behavior under simultaneous heating-hydration for nuclear waste storage applications. In: Fratta, D.O., Puppala, A.J., Muhunthan, B. (eds.): GeoFlorida 2010: Advances in Analysis, Modeling & Design. Geotechnical Special Publication 199: 470-479.

Gómez-Espina, R. & Villar, M.V. 2009. State of compacted MX-80 bentonite after simulation of thermo-hydraulic conditions in deep geological storage. In: Neil C. Hyatt, David A. Pickett, Raul B. Rebak (eds.): Scientific Basis for Nuclear Waste Management XXXII. Mater. Res. Soc. Symp. Proc. 1124, 1124-Q07-08, pp 289-294. Materials Research Society, Warrendale, PA.

Geet, M.; Bastiens, W.; Volckaert, G.; Weetjens, E.; Sillen, X.; Gens, A.; Villar, M.V.; Imbert, Ch.; Filippi, M. & Plas, F. 2008. Installation and evaluation of a large-scale in situ shaft seal experiment in Boom Clay. Clay in Natural and Engineered Barriers for Radioactive Waste Confinement. Selected papers from the 3rd International Meeting Lille September 2007. Science and Technology Series 334: 95-109. Andra. ISBN: 978-2-916162-02-7.

Sánchez, M.; Villar, M.V.; Gómez-Espina, R., Lloret, A. & Gens, A. 2008. Swelling pressure in compacted bentonite: laboratory tests and modelling. In: Toll, D.G.; Augarde, C.E.; Gallipoli, D. & Wheeler, S.J. (eds.): Unsaturated soils: Advances in Geo-engineering. Proceedings of the first European Conference on unsaturated soils, E-UNSAT 2008. Durham, UK, July 2-4 2008. CRC Press/Balkema. Taylor & Francis Group, London. 667-673.

Villar, M.V. & Gómez-Espina, R. 2008. Effect of temperature on the water retention capacity of FEBEX and MX-80 bentonites. In: Toll, D.G.; Augarde, C.E.; Gallipoli, D. & Wheeler, S.J. (eds.): Unsaturated soils: Advances in Geo-engineering. Proceedings of the first European Conference on unsaturated soils, E-UNSAT 2008. Durham, UK, July 2-4 2008. CRC Press/Balkema. Taylor & Francis Group, London. 257-262. 

Fernandez, A. M., Melon, A.M., Sanchez, D.M., Galan, M.P., Morante, R., Gutierrez-Nebot, L., Turrero, M.J., Escribano, A. 2008. Changes on the mineralogical and physical properties of FEBEX bentonite due to its contact with hyperalkaline pore fluids in infiltration tests. Mat. Res. Soc. Symp. Proc. ISBN: 978-1-60511-079-0, Vol.1107, 483-491

Villar, M.V., A.M. Fernández, R. Gómez, J.F. Barrenechea, F.J. Luque, P.L. Martín & J.M. Barcala. 2007. State Of A Bentonite Barrier After 8 Years Of Heating And Hydration In The Laboratory. In: D.S. Dunn, C. Poinssot, B. Begg (eds.): Scientific Basis for Nuclear Waste Management XXX. Mater. Res. Soc. Symp. Proc. 985, 0985-NN11-19. Materials Research Society, Warrendale, PA.

Sánchez, M.; Villar, M.V.; Lloret, A. & Gens, A. 2007. Analysis of the expansive clay hydration under low hydraulic gradient. In: Experimental Unsaturated Soil Mechanics. Springer Proceedings in Physics, vol. 112. Springer, Berlin. 309-318.

Villar, M.V. & Gómez-Espina, R. 2007. Retention curves of two bentonites at high temperature. In: Experimental Unsaturated Soil Mechanics. Springer Proceedings in Physics, vol. 112. Springer, Berlin. 267-274.

Villar, M.V. & Lloret, A. 2006. Experimental Investigation on the Mechanical Behaviour of Unsaturated Bentonite at High Temperature. In: Miller, Zapata, Houston & Fredlund (eds.). Unsaturated Soils 2006. Geotechnical Special Publication 147. Vol 2: 1719-1730. ASCE.

Martín, P.L., Barcala, J.M., García-Gutiérrez, M. 2006. Thermo-hydro-mechanical instrumentation in a long-term large-scale buffer material test: Mock-up experiment at CIEMAT. 5th ICEG Environmental Geotechnics: Opportunities, Challenges and Responsibilities for Environmental Geotechnics - Proceedings of the ISSMGE 5th Int. Congress. Vol. 1: 577-584

Villar, M.V.; Sánchez, M.; Lloret, A.; Gens, A. & Romero, E. 2005. Experimental and numerical study of the THM behaviour of compacted FEBEX bentonite in small-scale tests. In: ALONSO, E.E. & LEDESMA, A. (eds.): Advances in understanding engineered clay barriers. A.A. Balkema Publishers, Leiden. 323-335. ISBN 04-1536-544-9.

Villar, M.V.; Romero, E. & Lloret, A. 2005. Thermo-mechanical and geochemical effects on the permeability of high-density clays. In: ALONSO, E.E. & LEDESMA, A. (eds.): Advances in understanding engineered clay barriers. A.A. Balkema Publishers, Leiden. 177-191. ISBN 04-1536-544-9.

Villar, M.V.; Martín, P.L. & Lloret, A. 2005. Determination of water retention curves of two bentonites at high temperature. In: TARANTINO, A.; ROMERO, E. & CUI, Y.J. (eds.): Advanced experimental unsaturated soil mechanics. Experus 2005. A.A. Balkema Publishers, London. 77-82. ISBN 04-1538-337-4.

Villar, M.V.; Romero, E.; Buenfil, C.; Lloret, A.; Martín, P.L. & Lambert, F. 2005. The application of the axis translation technique to the triaxial testing of unsaturated soils. In: BILSEL, H. & NALBANTOGLU, Z. (eds.): Problematic soils. Proceedings of the Internacional Conference on Problematic Soils Geoprob 2005. Vol. 1. Eastern Mediterranean University Press, Famagusta. 87-94. ISBN 975-8401-22-X.

Martín, P.L., Barcala, J.M. 2005. Effects of over-heating on the performance of the engineering clayed barriers of the mock-up test. In: ALONSO, E.E. & LEDESMA, A. (eds.): Advances in understanding engineered clay barriers. A.A. Balkema Publishers, Leiden. 391-412. ISBN 04-1536-544-9.

Villar, M.V. & Lloret, A. 2004. Temperature influence on the mechanical behaviour of a compacted bentonite. In: STEPHANSSON, O.; HUDSON, J.A. & JING, L. (eds.): Coupled thermo-hydro-mechanical-chemical processes in geo-systems. Fundamentals, modelling, experiments and applications. Geo-Engineering Book Series, vol.2. Elsevier, Amsterdam. 305-310. ISBN: 0-08-044525-X.

Martín, P.L.; Villar, M.V.; García, M. & Yllera, A. 2001. Ensayos en maqueta y de apoyo al ensayo “in situ”: maqueta FEBEX y maqueta geoquímica. Procesos relevantes y dificultades de caracterización. In: IV Jornadas de investigación y desarrollo tecnológico en gestión de residuos radiactivos. Volumen IV. Publicación Técnica ENRESA 10/2001. ENRESA, Madrid. 9-28. ISSN 1134-380X.

Martín, P.L.; Villar, M.V. & Yllera, A. 2001. Diseño, construcción, instrumentación, monitorización y gestión de datos de ensayos a escala real del comportamiento térmico, hidraúlico, y mecánico de las barreras arcillosas de ingeniería (FEBEX, PRO- TOTYPE, HE). Ensayo en maqueta. In: IV Jornadas IDT en gestión de residuos radiactivos TERRA INNOVA 2000. Resúmenes y abstracts. Publicación Técnica ENRESA 2/2001. ENRESA, Madrid. 59-60.

Dereeper, B.; Volckaert, G.; Imbert, Ch. & Villar, M.V. 2001. Pellets/powder mixture of bentonite for backfill and sealing of HLW. In: ADACHI, K. & FUKUE, M.(eds.): Clay Science for Engineering. Balkema, Rotterdam. 487-490. ISBN 90 5809 175 9. 

Villar, M.V. & Lloret, A. 2001. Variation of the intrinsic permeability of expansive clay upon saturation. In: ADACHI, K. & FUKUE, M.(eds.): Clay Science for Engineering. Balkema, Rotterdam. 259-266. ISBN 90 5809 175 9.

Villar, M.V. & Martín, P.L. 1996. Suction controlled oedometer tests in montmorillonite clay. Preliminary results. In: Bentley, S.P.(ed): Enginering geology of waste disposal. Geological Society Engineering Geology Special Publication, vol. 11. The Geological Society, London. 309-311. ISBN 1-897799-46-2.

Villar, M.V. 1995. First results of suction controlled oedometer tests in highly expansive montmorillonite. In: ALONSO, E.E. & DELAGE, P. (eds): Unsaturated soils. Proceedings of the First International Conference on Unsaturated Soils (Paris). Balkema, Rotterdam. 207-213. ISBN 90 5410 583 6.

Villar, M.V., Gutiérrez-Álvarez, C., Campos, G. 2022. Bentonite swelling into a void under suction or water flow. Acta Geotechnica. https://doi.org/10.1007/s11440-022-01702-6

Villar, M.V., Iglesias, R.J., Gutiérrez-Álvarez, C., Carbonell, B. 2021a. Pellets/block bentonite barriers: laboratory study of their evolution upon hydration. Engineering Geology. 106272. https://doi.org/10.1016/j.enggeo.2021.106272

Villar, M.V., Carbonell, B., Martín, P.L., Gutiérrez-Álvarez, C. 2021. The role of interfaces in the bentonite barrier of a nuclear waste repository on gas transport. Engineering Geology 286: 106087. https://doi.org/10.1016/j.enggeo.2021.106087

Gutiérrez-Rodrigo, V., Martín, P.L., Villar, M.V.. 2020. Effect of interfaces on gas breaktrough pressure in compactedbentonite used as engineered barrier for radioactive waste disposal. Process Safety and Environmental Protection 149: 244-257. https://doi.org/10.1016/j.psep.2020.10.053.

Villar, M.V., Iglesias, R.J., García-Siñeriz, J.L. 2020. State of the in situ Febex test (GTS, Switzerland) after 18 years: A heterogeneous bentonite barrier after 18 years operation. Environmental Geotechnics 7(2): 147-159. https://doi.org/10.1680/jenge.17.00093

Zheng, L., Xua, H., Rutqvist, J., Reagan, M., Birkholzer, J. Villar, M.V., Fernández, A.M. 2020. The hydration of bentonite buffer material revealed by modeling analysis of a long-term in situ test. Applied Clay Science 185. https://doi.org/10.1016/j.clay.2019.105360.

Villar, M.V., Iglesias, R.J., García-Siñeriz, J.L., Lloret, A., Huertas, F. 2020. Physical evolution of a bentonite buffer during 18 years of heating and hydration. Engineering Geology 264: 105408. https://doi.org/10.1016/j.enggeo.2019.105408.

Villar, M.V., Campos, G., Gutiérrez-Nebot, L., Arroyo, X. 2019. Effect of prolonged drying at high temperature on the water retention capacity of bentonite (FEBEX-DP samples). Applied Clay Science 182: 105290. https://doi.org/10.1016/j.clay.2019.105290

Carbonell, B., Villar, M.V., Martín, P.L., Gutiérrez-Álvarez, C. 2019. Gas transport in compacted bentonite after 18 years under barrier conditions. Geomechanics for Energy and the Environment 17: 66-74. https://doi.org/10.1016/j.gete.2018.03.001.

Fernandez, A.M., S. Kaufhold, D.M. Sanchez-Ledesma, J.J. Rey, A. Melon, L.M. Robredo, S. Fernandez, M.A. Labajo, M.A. Clavero. 2018. Evolution of the THC conditions in the FEBEX in situ test after 18 years of experiment: Smectite crystallochemical modifications after interactions of the bentonite with a C-steel heater at 100 °C. Applied Geochemistry 98: 152–171. https://doi.org/10.1016/j.apgeochem.2018.09.008

Villar, M.V., Iglesias, R.J., Gutiérrez-Álvarez, C., Carbonell, B. 2018. Hydraulic and mechanical properties of compacted bentonite after 18 years in barrier conditions. Applied Clay Science 160: 49-57. DOI information: https://doi.org/10.1016/j.clay.2017.12.045 

García-Olivares, A., Agüero, A., Haupt, B.J., Marcos, M.J., Villar, M.V., de Pablos, J.L. 2017. A system of containment to prevent oil spills from sunken tankers. Science of the Total Environment 593-594: 242-252. DOI: https://doi.org/10.1016/j.scitotenv.2017.03.152

Villar, M.V., Martín, P.L., Romero, F.J., Iglesias, R.J., Gutiérrez-Rodrigo, V. 2016. Saturation of barrier materials under thermal gradient. Geomechanics for Energy and the Environment 8: 38-51. https://doi.org/10.1016/j.gete.2016.05.004.

Sánchez, M.; Gens, A.; Villar, M.V.; Olivella, S. 2016. Fully Coupled Thermo-Hydro-Mechanical Double-Porosity Formulation for Unsaturated Soils. International Journal of Geomechanics 16(6): D4016015. DOI: https://doi.org/10.1061/(ASCE)GM.1943-5622.0000728.

Gómez-Espina, R. & Villar, M.V. 2016. Time evolution of MX-80 bentonite geochemistry under thermo-hydraulic gradients. Clay Minerals 51(2): 145-160. DOI: https://doi.org/10.1180/claymin.2016.051.2.03.

Chaparro, M.C., Saaltink, M.W. & Villar, M.V. 2015. Characterization of concrete by calibrating thermo-hydraulic multiphase flow models. Transport in Porous Media 109(1): 147-167. DOI: https://doi.org/10.1007/s11242-015-0506-9.

García-Siñeriz, J.L., Villar, M.V., Rey, M. & Palacios, B. 2015. Engineered barrier of bentonite pellets and compacted blocks: state after reaching saturation. Engineering Geology 192: 33-45. DOI: https://doi.org/10.1016/j.enggeo.2015.04.002.

Gómez-Espina, R. & Villar, M.V. 2015. Effects of heat and humidity gradients on MX-80 bentonite geochemistry and mineralogy. Applied Clay Science 109-110: 39-48. DOI: https://doi.org/10.1016/j.clay.2015.03.012.

Campos, R., Barrios I., Lillo, J. 2015. Experimental CO2 injection: Study of physical changes in sandstone porous media using Hg porosimetry and 3D pore network models. Energy Reports 1: 71–79. https://www.sciencedirect.com/science/article/pii/S2352484715000141

Fernández, A.M., D.M. Sánchez-Ledesma, C. Tournassat, A. Melón, E.C. Gaucher, J. Astudillo, A. Vinsot. 2014. Applying the squeezing technique to highly consolidated clayrocks for pore water characterisation: Lessons learned from experiments at the Mont Terri Rock Laboratory. Applied Geochemistry 49, 2-21. https://doi.org/10.1016/j.apgeochem.2014.07.003

Villar, M.V., Martín, P.L., Bárcena, I., García-Siñeriz, J.L., Gómez-Espina R. & Lloret A. 2012. Long-term experimental evidences of saturation of compacted bentonite under repository conditions. Engineering Geology 149-150: 57-69. DOI: https://doi.org/10.1016/j.enggeo.2012.08.004.

Villar, M.V.; Gómez-Espina, R. & Gutiérrez-Nebot, L. 2012. Basal spacings of compacted bentonite. Applied Clay Science 65-66: 95-105. DOI: https://doi.org/10.1016/j.clay.2012.05.010

Jacinto, A.; Villar, M.V. & Ledesma, A. 2012. Influence of water density on the water-retention curve of expansive clays. Géotechnique 62(8): 657-667. DOI: https://doi.org/10.1680/geot.7.00127.

Gens, A.; Valleján, B.; Sánchez, M.; Imbert, C.; Villar, M.V. & Van Geet, M. 2011. Hydromechanical behaviour of a heterogeneous compacted soil: experimental observations and modelling. Géotechnique 61(5): 367-386. DOI: https://doi.org/10.1680/geot.SIP11.P.015

Fernández, A.M. & Villar, M.V. 2010. Geochemical behaviour of a bentonite barrier in the laboratory after up to 8 years of heating and hydration. Applied Geochemistry 25: 809-824. DOI: https://doi.org/10.1016/j.apgeochem.2010.03.001.

Gómez-Espina, R. & Villar, M.V. 2010. Geochemical and mineralogical changes in compacted MX-80 bentonite submitted to heat and water gradients. Applied Clay Science 47: 400-408. DOI: https://doi.org/10.1016/j.clay.2009.12.004.

Jacinto, A.C.; Villar, M.V.; Gómez-Espina, R. & Ledesma, A. 2009. Adaptation of the van Genuchten expression to the effects of temperature and density for compacted bentonites. Applied Clay Science 42: 575-582. DOI: https://doi.org/10.1016/j.clay.2008.04.001.

Castellanos, E.; Villar, M.V.; Romero, E.; Lloret, A. & Gens, A. 2008. Chemical impact on the hydro-mechanical behaviour of high-density FEBEX bentonite. Physics and Chemistry of the Earth 33: S516-S526. DOI: https://doi.org/10.1016/j.pce.2008.10.056.

Villar, M.V.; Sánchez, M. & Gens, A. 2008. Behaviour of a bentonite barrier in the laboratory: experimental results up to 8 years and numerical simulation. Physics and Chemistry of the Earth 33: S476-S485. DOI: https://doi.org/10.1016/j.pce.2008.10.055.

Villar, M.V. & Lloret, A. 2008. Influence of dry density and water content on the swelling of a compacted bentonite. Applied Clay Science 39: 38-49. DOI: https://doi.org/10.1016/j.clay.2007.04.007.

Villar, M.V. 2007. Water retention of two natural compacted bentonites. Clays and Clay Minerals 55(3): 311-322. DOI: https://doi.org/10.1346/CCMN.2007.0550307.

Lloret, A. & Villar, M.V. 2007. Advances on the knowledge of the thermo-hydro-mechanical behaviour of heavily compacted FEBEX bentonite. Physics and Chemistry of the Earth, Parts A/B/C 32 (8-14): 701-715. DOI: https://doi.org/10.1016/j.pce.2006.03.002.

Villar, M.V.& Lloret, A. 2007. Dismantling of the first section of the FEBEX in situ test: THM laboratory tests on the bentonite blocks retrieved. Physics and Chemistry of the Earth, Parts A/B/C 32 (8-14): 716-729. DOI: https://doi.org/10.1016/j.pce.2006.03.009.

Imbert, Ch. & Villar, M.V. 2006. Hydro-mechanical response of a bentonite pellets/powder mixture upon infiltration. Applied Clay Science 32: 197-209. DOI: https://doi.org/10.1016/j.clay.2006.01.005.

Villar, M.V. 2006. Infiltration tests on a granite/bentonite mixture: Influence of water salinity. Applied Clay Science 31(1-2): 96-109. DOI: https://doi.org/10.1016/j.clay.2005.07.007.

Orozco, J., Baldi, A., Martín, P.L., Bratov, A., Jiménez, C. 2006. Monitoring of bentonite pore water with a probe based on solid-state microsensors. Analytica Chimica Acta 579(1): 95-101. DOI: https://doi.org/10.1016/j.aca.2006.07.030

Villar, M.V.; Martín, P.L. & Barcala, J.M. 2005. Modification of physical, mechanical and hydraulic properties of bentonite by thermo-hydraulic gradients. Engineering Geology 81(3): 284-297. DOI: https://doi.org/10.1016/j.enggeo.2005.06.012. 

Romero, E.; Villar M.V. & Lloret, A. 2005. Thermo-hydro-mechanical behaviour of two heavily overconsolidated clays. Engineering Geology 81(3): 255-268. DOI: https://doi.org/10.1016/j.enggeo.2005.06.011.

Villar, M.V.; García-Siñeriz, J.L.; Bárcena I. & Lloret, A. 2005. State of the bentonite barrier after five years operation of an in situ test simulating a high level radioactive waste repository. Engineering Geology 80(3-4): 175-198. DOI: https://doi.org/10.1016/j.enggeo.2005.05.001.

Martín, P.L., Barcala, J.M. 2005. Large scale buffer material test: Mock-up experiment at CIEMAT. Engineering Geology 81(3): 298-316. https://doi.org/10.1016/j.enggeo.2005.06.013

Villar, M.V. & Lloret, A. 2004. Influence of temperature on the hydro-mechanical behaviour of a compacted bentonite. Applied Clay Science 26(1-4): 337-350. DOI: https://doi.org/10.1016/j.clay.2003.12.026.

Lloret, A.; Villar, M.V.; Sánchez, M.; Gens, A.; Pintado, X. & Alonso, E.E. 2003. Mechanical behaviour of heavily compacted bentonite under high suction changes. Géotechnique 53(1): 27-40. DOI: https://doi.org/10.1680/geot.53.1.27.37258.

Jimenez, C., Moreno, L., De Haro, C., Muñoz, F.X., Florido, A., Rivas, P., Fernández, A.M., Martín, P.L., Bratov, A., Dominguez, C. 2003. Development of a multiparametric system based on solid-state microsensors for monitoring a nuclear waste repository. Sensors and Actuators, B: Chemical 91(1-3): 103-108. https://doi.org/10.1016/S0925-4005(03)00073-X

Cuevas, J.; Villar, M.V.; Martín, M.; Cobeña, J.C. & Leguey, S. 2002. Thermo-hydraulic gradients on bentonite: time-dependent distribution of soluble salts, microstructural effects and modification of the hydraulic and mechanical behaviour. Applied Clay Science 22(1-2): 25-38. DOI: https://doi.org/10.1016/S0169-1317(02)00109-6.

Villar, M.V. 1999. Investigation of the behaviour of bentonite by means of suction-controlled oedometer tests. Engineering Geology 54 (1-2): 67-73. DOI: https://doi.org/10.1016/S0013-7952(99)00062-9.

Cuevas, J.; Villar, M.V.; Fernández, A.M; Gómez, P. & Martín, P.L. 1997. Pore waters extracted from compacted bentonite subjected to simultaneous heating and hydration. Applied Geochemistry 12: 473-481. DOI: https://doi.org/10.1016/S0883-2927(97)00024-3.

Villar, M.V.; Cuevas, J. & Martin, P.L. 1996. Effects of heat/water flow interaction on compacted bentonite. Preliminary results. Engineering Geology 41: 257-267. DOI: https://doi.org/10.1016/0013-7952(95)00037-2.

Villar, M.V. & Rivas, P. 1994. Hydraulic properties of montmorillonite-quartz and saponite-quartz mixtures. Applied Clay Science 9: 1-9. https://doi.org/10.1016/0169-1317(94)90011-6.

Villar, M.V. 2018. Desmantelamiento del ensayo FEBEX-DP: una simulación en condiciones naturales del concepto español de almacenamiento de residuos de alta actividad en funcionamiento durante 18 años. Estratos 120: 44-51. ENRESA.

Villar, M.V. & Fernández, A.M. 2015. Laboratorios de caracterización de arcillas en el CIEMAT. Estratos 109: 10-14. ENRESA.

Rivas, P.; Martín, P.L.; Fernández, A.M.; Villar, M.V.; García, M. & Yllera, A. 2001. El ensayo en maqueta: un experimento realista de la barrera de arcilla. Estratos 60: 10-15.

Cuevas, J.; Fernández, R.; Ruiz, A.I.; de Soto, I.; Vigil, R.; Escribano, A.; Torres, E.; Villar, M.V. & Turrero, M.J. 2012. Mineral reaction front developed in a 4.5 years test for the study of concrete-bentonite interface. Macla 16: 128-129.

Gutiérrez-Rodrigo, V.; Villar, M.V.; Martín, P.L. & Romero, F.J. 2012. Determinación de las propiedades de transporte de gas en bentonita. Macla 16: 126-127. 

Gómez-Espina, R.; Villar, M.V. & Gutiérrez, V. 2012. Efectos de la superficie específica BET en bentonitas sometidas a ensayos termohidráulicos. Macla 16: 106-107.

Villar, M.V., Gómez-Espina, R. & Lloret, A. 2010. Experimental investigation into temperature effect on hydro-mechanical behaviours of bentonite. Journal of Rock Mechanics and Geotechnical Engineering 2(1): 71-78.

R. Gómez Espina, M.V. Villar Galicia, J. Fernández Barrenechea, J. Luque Del Villar, J. Cuevas Rodríguez. 2008. Cambios Mineralógicos en una Bentonita tras 7,6 años de Tratamiento Termo-Hidráulico. Macla 9: 123-124.

Gómez Espina, R. & Villar Galicia, M.V. 2006. Estudio de la bentonita FEBEX sometida a las condiciones de un almacenamiento geológico profundo. Macla 6: 221-224.

Villar, M.V.; Pérez del Villar, L.; Martín, P.L.; Pelayo, M.; Fernández, A.M.; Garralón, A.; Cuevas, J.; Leguey, S.; Caballero, E.; Huertas, F.J.; Jiménez de Cisneros, C.; Linares, J.; Reyes, E.; Delgado, A.; Fernández-Soler, J.M. & Astudillo J. 2006. The study of Spanish clays for their use as sealing materials in nuclear waste repositories: 20 years of progress. Journal of Iberian Geology 32(1): 17-36.

Villar, M.V.; Astudillo, J. & Huertas, F. 2006. Selection and characterisation of a reference sealing material: the Spanish case. Chinese Journal of Rock Mechanics and Engineering 25(4): 768-780.

 

Villar, M.V., Iglesias, R.J., Gutiérrez-Álvarez, C., Carbonell, B., Real, E., Brea, N. 2022. Laboratory tests on bentonite homogenisation performed by CIEMAT: Saturation of block/pellets systems (Project BEACON). Informes Técnicos CIEMAT 1509. Madrid, 110 pp. https://www.ciemat.es/portal.do?TR=A&IDR=1&identificador=998

Villar, M.V., Gutiérrez-Álvarez, C., Campos, G. 2022. Laboratory tests on bentonite homogenisation performed by CIEMAT: Gap filling (Project BEACON). Informes Técnicos CIEMAT 1510. Madrid, 72 pp. https://www.ciemat.es/portal.do?TR=A&IDR=1&identificador=997

Villar, M.V., Iglesias, R.J., Gutiérrez-Álvarez, C. 2022. THM column cell with MX-80 pellets simulating the HE-E in situ experiment for 10 years: online results and final physical state. Informes Técnicos CIEMAT 1507. Madrid, 65 pp. https://www.ciemat.es/portal.do?TR=A&IDR=1&identificador=953

Villar, M.V., Cuevas, J., Melón, A.M., Gutiérrez-Álvarez, C., Ruiz, A.I., Ortega, A., Iglesias, R.J., González, A.E., Brea, N., Fernández, R., Real, E. 2021. Project Minalben. Report on postmortem analyses of samples from cells running for 2.5 years (C3, C4 and C5). Technical Report CIEMAT/DMA/2G219/1/21. Madrid, 86 pp

Villar, M.V., Armand, G., Conil, N., de Lesquen, Ch., Herold, Ph., Simo, E., Mayor, J.C., Dizier, A., Li, X., Chen, G., Leupin, O., Niskanen, M.,  Bailey, M.,  Thompson, S., Svensson, D., Sellin, P., Hausmannova, L. 2021. D7.1 HITEC. Initial State-of-the-Art on THM behaviour of i) Buffer clay materials and of ii) Host clay materials. Deliverable D7.1 HITEC. EURAD Project, Horizon 2020 No 847593. 214 pp. https://www.ejp-eurad.eu/publications/eurad-deliverable-71-initial-sota-thm-behaviour-i-buffer-clay-materials-and-ii-host

Campos, G., Villar, M.V. 2018. ATC: Curvas de retención de muestras del sondeo SG-125. Informe Técnico CIEMAT/DMA/2G218/6/18. Madrid, 41 pp. http://documenta.ciemat.es/handle/123456789/756

Campos, G., Villar, M.V. 2018. Water retention curves of bentonite samples of the FEBEX Dismantling Project (FEBEX-DP). Informe Técnico CIEMAT 1432. Madrid, 44 pp. http://documenta.ciemat.es/handle/123456789/757

Villar, M.V., Carbonell, B., Martín, P.L., Gutiérrez-Álvarez, C., Barcala, J.M. 2018. Gas permeability of bentonite samples of the FEBEX Dismantling Project (FEBEX-DP). Informe Técnico CIEMAT 1431. Madrid, 89 pp. http://documenta.ciemat.es/handle/123456789/761

Villar, M.V., Iglesias, R.J., Gutiérrez-Álvarez, C., Carbonell, B., Campos, R., Campos, G., Martín, P.L., Castro, B. 2018. FEBEX-DP: Thermo-hydro-mechanical postmortem analysis of bentonite performed at CIEMAT. Technical report CIEMAT/DMA/2G216/2/16. NAB16-024. Madrid, 134 pp. http://documenta.ciemat.es/handle/123456789/760

Mazurek, M., T. Al, M. Celejewski, I.D. Clark, A.M. Fernandez, L. Kennell-Morrison, J.M. Matray, S. Murseli, T. Oyama, S. Qiu, D. Rufer, G. St-Jean, H.N. Waber & C. Yu. 2017. Mont Terri DB-A Experiment: Comparison of Pore-water Investigations Conducted by Several Research Groups on Core Materials from the BDB-1 Borehole. Mont Terri Technical Report TR2017-01. https://www.mont-terri.ch/en/documentation/technical-reports.detail.document.html/mont-terri-internet/en/documents/technical-reports/TR2017-01.pdf.html

Fernández, A.M., Sánchez-Ledesma, D.M., Melón, A.M., Robredo, L.M., Labajo, M.A., Sánchez, M., Clavero, M.A., González, A.E., Rey, J.J., Gutiérrez-Nebot, L. 2016. Síntesis geoquímica, mineralógica y petrográfica del sustrato geológico del ATC: Características de las unidades litoestratigráficas LBS, YB, LBI y UI en el entorno de Villar de Cañas (Cuenca). Informe final. Informe Técnico CIEMAT/DMA/2G214/1/2016. Madrid, 150 pp.

M.V. Villar, F.J. Romero, P.L. Martín, V.Gutiérrez-Rodrigo, J.M. Barcala. 2015. Gas transport in Opalinus clay. Informes Técnicos CIEMAT 1378. Madrid, 40 pp. DOI: https://doi.org/10.13140/RG.2.2.28594.91846 http://documenta.ciemat.es/handle/123456789/762

Villar, M.V. Campos, R., Gutiérrez-Nebot, L. 2014. EB experiment. Laboratory post-mortem analyses report. EC Contract 249681 PEBS. PEBS Deliverable 2.1-7. Technical Report CIEMAT/DMA/2G210/01/2014. Madrid, 34 pp. http://documenta.ciemat.es/handle/123456789/134

Villar, M.V., Gutiérrez-Rodrigo, V., Martín, P.L., Romero, F.J., Barcala, J.M. 2013. Gas transport in bentonite. Informes Técnicos CIEMAT 1301. Madrid, 63 pp. DOI: https://doi.org/10.13140/RG.2.2.14334.28489 http://documenta.ciemat.es/handle/123456789/763 http://documenta.ciemat.es/handle/123456789/90

Gómez-Espina, R. & Villar, M.V. 2013. Modificaciones en la bentonita MX-80 compactada sometida a tratamiento termo-hidráulico. Informes Técnicos CIEMAT 1290. Madrid, 85 pp. http://documenta.ciemat.es/handle/123456789/100

Fernández, A.M., Sánchez-Ledesma, D.M., Tournassat, C., Melón, A., González, A.E., Gaucher, E., Astudillo, J., Vinsot, A. 2013. Applying squeezing technique to clayrocks: lessons learned from experiments at Mont Terri Rock Laboratory. Informes Técnicos Ciemat1300. Madrid, 88 pp. http://documenta.ciemat.es/handle/123456789/110

Villar, M.V. & Romero, F.J. 2012. Water retention curves of Opalinus clay. Informes Técnicos CIEMAT 1262. Octubre 2012. CIEMAT, Madrid, 33 pp. DOI: https://doi.org/10.13140/RG.2.2.17689.72808 http://documenta.ciemat.es/handle/123456789/765

Villar, M.V., Martín, P.L., Romero, F.J., Gutiérrez-Rodrigo, V. & Barcala. J.M. 2012. Gas and water permeability of concrete. Informes Técnicos CIEMAT 1261. Octubre 2012. CIEMAT, Madrid, 45 pp. http://documenta.ciemat.es/handle/123456789/766

Fernández, A.M., Melón, A., Sánchez, D.M., Gutierrez-Nebot, L., Rodríguez, N., Palomo, C., Sánchez, M., Galán, P., Gonzalez, A.E.. 2012. Mineralogía, geoquímica y propiedades fisicoquímicas de los materiales de cobertera de El Cabril. Informe Técnico CIEMAT/DMA/2G208/7/11. Madrid, 55 pp.

Fernández, A.M., Sánchez, D.M., Melón, A., Alonso, U., Missana, T., Morante, R., Gonzalez, A.E. 2012. Study of the pore water in the BDI-B1 borehole from the Opalinus Clay formation at the Mont Terri Rock Laboratory after 7.6 years of experiment. Mont Terri Technical Note 2011-25, 50 pp.

Fernández, A.M., Melón, A., Sánchez-Ledesma, D.M., Morante, R., Gutierrez-Nebot, L., Alba, M.D., Aorta, M.M. 2011. Gas and water adsorption behaviour of in Opalinus Clay samples from borehole BHT-1. Mont Terri Technical Note 2009-46c, 61 pp.

Gómez, R. & Villar, M.V. 2010. Geochemical and mineralogical changes in compacted MX-80 bentonite submitted to heat and water gradients. Informes Técnicos CIEMAT 1199. Marzo 2010. Madrid, 33 pp. http://documenta.ciemat.es/handle/123456789/767

Villar, M.V. & Gómez-Espina, R. 2009. Report on thermo-hydro-mechanical laboratory tests performed by CIEMAT on FEBEX bentonite 2004-2008. Informes Técnicos CIEMAT 1178. Madrid, 67 pp. Agosto 2009. DOI: https://doi.org/10.13140/RG.2.2.10087.55208 http://documenta.ciemat.es/handle/123456789/768

Fernández, A.M., Melón, A., Sánchez, D.M., Galán, P., García, C., Gonzalez, A.E., Morante, R., Calderón, A., Gutierrez-Nebot, L. 2009. Physical, Geochemical and Mineralogical Characterization of the Opalinus Clay at Mont Terri from Core Samples of the Borehole BHT-1 located in the Gallery 08. Technical Note 2009-46a, 38 pp.

M.V. Villar, A. Udías, I. Cañamón & J. Robles. 2006. Estudio experimental de la deformabilidad de un material geológico: caracterización inicial e identificación de parámetros. Informes Técnicos CIEMAT 1080. CIEMAT, Madrid, 45 pp. Junio 2006. DOI: https://doi.org/10.13140/RG.2.2.23509.32480 http://documenta.ciemat.es/handle/123456789/776

M.V. Villar, R. Gómez-Espina & P.L. Martín. 2006. Behaviour of MX-80 bentonite at unsaturated conditions and under thermo-hydraulic gradient. Work performed by CIEMAT in the context of the TBT project. Informes Técnicos CIEMAT 1081. CIEMAT, Madrid, 45 pp. July 2006. DOI: https://doi.org/10.13140/RG.2.2.30062.92482 http://documenta.ciemat.es/handle/123456789/777

Villar, M.V. 2005. MX-80 bentonite. Thermo-hydro-mechanical characterisation performed at CIEMAT in the context of the Prototype Project. Informes Técnicos CIEMAT 1053. CIEMAT, Madrid, 39 pp. Febrero 2005. http://documenta.ciemat.es/handle/123456789/778

Villar, M.V. 2004. Thermo-hydro-mechanical characterisation of the bentonite of a simulated HLW repository after five years operation (in situ test of the FEBEX Project). Informes Técnicos CIEMAT 1049. CIEMAT, Madrid, 61 pp. DOI: https://doi.org/10.13140/RG.2.2.30220.21123 http://documenta.ciemat.es/handle/123456789/779

Villar, M.V. 2004. Thermo-hydro-mechanical characteristics and processes in the clay barrier of a high level radioactive waste repository. State of the art report. Informes Técnicos CIEMAT 1044. CIEMAT, Madrid, 75 pp. http://documenta.ciemat.es/handle/123456789/796

Melón, A.M., Fernández, A.M., Turrero, M.J. 2003. Pore water chemistry (PC): Measurements of redox potential and pH on Opalinus Clay core samples. Mont Terri Technical Note TN 2003-29. 34 pp.