Ioannis Stefanou, Principal Investigator
Ioannis Stefanou is currently Professor at Ecole Centrale de Nantes (ECN), France. He studied at the School of Civil Engineering of the National Technical University of Athens and did his thesis at the Laboratory of Geomaterials of the School of Applied Mathematics and Physics Sciences of the same institution. He is the author of several articles in major multi-disciplinary scientific journals and leading peer-reviewed international journals in the fields of mechanics and geomechanics. He develops novel theoretical, numerical and experimental tools focusing on redefining and going beyond “failure” in design. His main research topics are the mechanics of (geo-)materials, geomechanics, fault reactivation and earthquake control.
For more details: CV
Associated scientists
Stéphanie Chaillat
Stéphanie Chaillat is CNRS Research Scientist since 2011 and works in the laboratory POEMS at ENSTA Paris. She received her PhD from Ecole Nationale des Ponts et Chaussées in 2008. Her research, always driven by realistic physical problems, concerns the proposition and study of fast algorithms and numerical methods to simulate wave propagation problems in large scale domains. Her expertise concerns numerical methods for PDEs, fast algorithms and efficient (including parallel) programming. She develops and improves the boundary element method for mechanical problems: simulation of seismic waves in the soil, underwater explosions in the ocean, contact problems, radiated noise in different configurations all this work is integrated in the fast solver COFFEE.
François Cornet†
François cornet is Professor Emeritus at the School and Observatory of Earth Sciences of the University of Strasbourg (EOST). His research activities focus on induced seismicity combining in-situ measurements and modeling. As an example, it is worth mentioning two PhD theses that he recently co-supervised. The first one (F. Masson, Thesis Director) is on geomechanical modeling of the ground motions detected by interferometry from satellite (imagery SARR), which were obtained on the area of the old mines of potash of Alsace (France). The second one (J. Schmittbuhl, Thesis Director) is on the modelling of changes in P-wave velocity propagation, which were determined using seismic tomography during hydraulic stimulation of the Soultz deep Enhanced Geothermal System (EGS) in Alsace (France). The measurements were carried out between 4.5 and 5 km depth. At the same time he continues cooperation with the University of Lulea in Sweden on stress measurements in deep drilling as well as cooperation with Leo Eisner (Czech Repub
lic) on the fields of pressure mapping in areas of active micro-seismicity induced by fluid injections. His research is leading to important conclusions regarding the notion of representative elementary volume.
Nicolas Moës
Nicolas MOËS is full Professor at the Ecole Centrale de Nantes (ECN, France) since 2001 and currently a senior member of the Institut Universitaire de France (IUF). He received his engineering degree from the University of Liège (ULg) and his PhD from the Ecole Normale Supérieure de Cachan under the guidance of Pierre Ladevèze. He is one of the co-inventor of the eXtended Finite Element Method (X-FEM). This work was initiated during his post-doctoral stay at Northwestern University in the team of Ted Belytschko (following another post-doc with professor Tinsley Oden at UT Austin). More recently, he has been developing with colleagues at Nantes a new model lying between fracture and damage mechanics coined the thick level set approach (TLS) as well as a new approach to solve contact formulations (and other variational inequalities as the Bingham fluid formulation). This work was funded by an advanced ERC grant (2012-2017). He received the young investigator award from the IACM (International Association for Computational Mechanics) in 2006 and was declared IACM fellow in 2008. In 2014, he received the silver medal from CNRS. Very recently, he also received a prize from the French academy of science: the ONERA prize.
Jean-François Semblat
Jean-François Semblat is Professor at ENSTA-Paris and researcher at the Institute of Mechanical Sciences and Industrial Applications (IMSIA). He is also president of the Department of Mechanics and Energetics at the Institut Polytechnique de Paris. His field of research spans from seismic wave propagation in complex geological structures, to dynamic soil-structure interaction, soil dynamics (including liquefaction) as well as structural dynamics. He mainly focuses on numerical approaches such as the Finite Element Method and the Boundary Element Method. He coordinates the national research project on liquefaction (ANR ISOLATE) and is involved in the national research project on the effects of surface waves on long period structures (ANR MODULATE). He is also member of the scientific committee of the French Association for Earthquake Eng. (AFPS) and of the French Society for Soil Mechanics (CFMS), member of the Technical Committee “Earthquake Geotechnical Engineering” (TC203) of the International Society of Soil Mechanics and Geotechnical Engineering and member of the editorial board of the Int. Jal of Geomechanics Soil Dynamics and Earthquake Eng. He published a book on Waves and vibrations in soils in 2009 (IUSS Press, with A. Pecker) and co-authored two MOOCs (Coursera) entitled Fundamentals of Waves and Vibrations (2019) and From Seismology to Earthquake Engineering (2021).
Jean Sulem
Jean Sulem is Professor and Research Director at ENPC. He is head of the Geotechnical Group, CERMES, of NAVIER laboratory and Chairman of the French Committee of Rock Mechanics (CFMR). He has significant contributions in rock mechanics (experimental and constitutive modelling), strain localization and bifurcation phenomena in geomechanics, discontinuous rock mass, fault mechanics and thermo-hydro-mechanical couplings in geomaterials.
Post-Doc collaborators
Philipp Braun
Philipp Braun has completed his PhD in the field of geomechanics at Navier Laboratory (ENPC, IFSTTAR, CNRS) at the Ecole des Ponts ParisTech (ENPC). He graduated with a M.Sc. degree in civil engineering from the Technical University Munich (TUM). During his Master’s studies he focused on geotechnical and earthquake engineering with stays at the University of Tokyo (UTokyo) and the Ecole des Ponts ParisTech. His current research interests lie in the experimental characterization of coupled thermo-hydro-mechanical processes in geomaterials and the development of new experimental methods and devices.
For more details: CV
Diego Gutiérrez-Oribio
Diego Gutiérrez-Oribio was born in México and received his M.S. degree and Bachelor degree in Mechatronic Engineering from the National Autonomous University of Mexico (UNAM), Mexico City, Mexico in 2016 and 2013, respectively. In 2021, he received his PhD in Electrical Engineering – Automatic Control (with honours) at UNAM. He is currently a post-doctoral member of the CoQuake group. His current research interests include the control and observation of earthquakes phenomena using robust and nonlinear algorithms, to compensate disturbances and/or uncertainties present in such problems.
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Benoit Lé
Benoît Lé graduated with a M. Sc. in computational Mechanics and a PhD from Ecole Centrale de Nantes (ECN), France. His PhD works was about modelling reinforced concrete, using the eXtended Finite Element method (X-FEM) for the steel reinforcements, and the Thick Level Set approach to fracture (TLS) for the concrete. He is now a research engineer at the Ecole Centrale de Nantes. His works focus on damage and fracture mechanics. In particular, he is involved in the implementation of the TLS in the finite element code eXlibris, developped at the Research Institute of Civil Engineering and Mechanics (GeM).
Filippo Masi
Filippo Masi has completed his PhD in the field of fast-dynamics and machine learning at GeM Laboratory at the Ecole Centrale de Nantes (ECN) and, previously at Navier Laboratory (ENPC, IFSTTAR, CNRS) at the Ecole des Ponts ParisTech (ENPC). He graduated from the University of Florence with honors in 2017 holding a Diploma in Mechanical Engineering and a Master’s Degree in Turbomachinery. During his Master’s studies he focused on structural engineering and shock wave dynamics. His current research interests lie in the numerical modeling of the response of ancient and modern masonry structures subjected to explosions and the development of machine learning-based constitutive models.
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Efthymios Papachristos
Efthymios Papachristos is a researcher in computational geomechanics. He holds a PhD in geomechanics from Université Grenoble Alpes (UGA), France. He has obtained his MSc in geomechanics, civil engineering and risks from Université Joseph Fourier and Grenoble-INP (currently UGA), in France, and his Ing-Diploma in mineral resources engineering from the Technical University of Crete (TUC), in Greece. During his engineering diploma he focused on 3D numerical modelling in tunneling at the Rock Mechanics Lab of TUC. In his MSc. he focused on asymptotic homogenization of fractured porous media at Lab 3SR (UGA,CNRS). During his PhD, at Lab 3SR (UGA,CNRS), he developed a 3D hydro-mechanical model for hydraulic fracturing in fractured rock-masses based on the discrete element method (DEM). After his studies he stayed in NAVIER Lab at Ecole Nationale des Ponts et Chaussées (ENPC), in France for post-doctoral research, where he got involved into fault mechanics. His current interests fall into the domain of coupled Thermo-Hydro-micro-Mechanical systems using DEM with applications on the mechanics of faults and earthquakes and A.I. based Earthquake Control.
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PhD students
Abdallah Aoude
Abdallah AOUDE does his PhD thesis on experimental design of earthquake control strategies. He graduated in 2019 from Beirut Arab University (BAU) holding a diploma in Civil Engineering. In 2021 he graduated first in his class from École Centrale de Nantes (ECN) holding a Master’s degree in Civil Engineering, Materials and structures in their environment. His PhD thesis builds upon existing experience and theories developed in the CoQuake group. His current research interests fall into developing and designing a large-scale analogue of fault for studying and testing earthquake nucleation and control.
For more details: CV
Laura Bagur
Laura Bagur is completing her PhD in numerical modeling of fault mechanics and earthquake control at ENSTA Paris, France, supervised by Dr. S. Chaillat, Pr. J.-F. Semblat, and Dr. I. Stefanou. She graduated from the Ecole Normale Supérieure Paris-Saclay (ENSPS), France, with honors in 2020 holding a Diploma in Mechanical Engineering and a Master’s Degree in Mechanical Modeling and Simulation of Coupled Structures and Systems. She holds a Teaching Degree in Industrial Sciences and Mechanical Engineering. During her Master’s studies, she focused on the Improvement of hierarchical matrices for 3D Elastodynamic problems with a complex wavenumber. Her current research interests in Three-Dimensional modeling of seismic and aseismic slip using Fast Boundary Element Methods. During the CoQuake action, her thesis aims at pushing the capabilities of Fast BEMs to efficiently solve multi-physic problems incorporating thermo-hydro-mechanical couplings, at stake in earthquake control.
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Alexandros Stathas
Alexandros Stathas does his PhD Thesis on multiscale numerical modeling of earthquake faults. He graduated from the National Technical University of Athens (NTUA) with honors in 2018 holding a Diploma in Civil Engineering and a Master’s Degree in Structural Engineering. He then obtained a master’s degree in Analysis and Design of Structures from NTUA. His research interests include soil structure interaction, shakedown analysis, plasticity in geotechnics and finite elements. During the CoQuake action he focuses on continuum mechanics, micromechanics and upscaling techniques developing the CoQuake’s “Numerical Geolab” platform.
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Georgios Tzortzopoulos
Georgios Tzortzopoulos does his PhD thesis on earthquake control using pertinent fault stimulating experimental techniques in the laboratory. He graduated in 2016 from the National Technical University of Athens (NTUA) holding a Diploma in Civil Engineering and a Master’s Degree in Structural Engineering. He did his Master Thesis at the Laboratory of Structural Analysis and Antiseismic Research of NTUA. In the meantime, he fulfilled his military obligations in Greece. His current research interests are oriented towards fault mechanics and earthquake control using advanced experimental techniques.
For more details: CV