Research at EPF


Established in 2007, Axis MECHANICS (ERMESS) aims to develop methods and tools for mechanical engineering for the design of safe mechanical structures.

Axis mechanics is interested in:

  • Experimental analysis and modeling of fatigue and fracture of materials and structures under stress since the first signs of damage, until failure;
  • The multi-scale modeling;
  • Additive manufacturing and 3D scanning.

Go to:


1/ Materials and Composites

  • Operating performance and degradation of materials and mechanical components;

3 Points bending test

  • Multi-scale modeling - from the local to the macroscopic scale

Modélisation multi-echelle

  • Reliability-analysis for the Inspection / Maintenance / Repair mechanical components


2/  Additive manufacturing and 3D scanning

  • Interoperability of additive manufacturing in complex systems;
  • Rapid tooling for the factory of the future;
  • Optimization of "smart" materials incorporating the analysis of sustained mechanical stress.

Fabrication additive et numérisation 3D


Permanent members 

Mahdi Chemki Enseignant Chercheur MécaniqueMahdi CHEMKHI: Master's Degree in Mechanical Engineering and Materials at the Higher School of Technical Sciences of Tunis (2008), Master in Mechanical Systems and Materials at the University of Technology of Troyes (2009), Doctorate in Mechanical System and Materials UTT (in the Laboratory of Mechanical Systems and Simultaneous Engineering - LASMIS) in 2014, ATER Section-60 at the UTT (2013 - 2014). Qualified in CNU sections 28, 33 and 60.
Mahdi CHEMKHI carries out his research at the Charles Delaunay Institute (Laboratory LASMIS) at the University of Technology of Troyes.

Research topics: Optimization of mechanical structures and improvement of the mechanical performances of parts resulting from Metallic Additive Manufacturing by SLM (Powder Metallurgy) by the development of mechanical and / or thermochemical surface treatments. Analysis and understanding of the relationships between microstructure and mechanical properties.

Keywords: Surface treatment, Additive metal fabrication, Materials selection and characterization, Fatigue, Tribology (wear and friction tests).

GardanJulien GARDAN : Degree in Materials Engineering at the University of Reims (2004), Master “Engineering Production Assisted by Computer (CAPI)” at the University of Reims (2005), PhD in Mechanical Systems and Materials  at UTT (LASMIS Laboratory) in 2011.
Julien GARDAN carries out his research at the Charles Delaunay Institute (LASMIS Laboratory) at the University of Technology of Troyes.

Research topics: Study of rapid manufacturing and 3D scanning through new applications. Integration of the wood as a new material. Anthropocentric conception.

Keywords: Digital engineering, rapid manufacturing, additive manufacturing, rapid prototyping, 3D scanning, user-centered design.

Ali MakkeAli MAKKE : Graduate in Mechanical Engineering at the Lebanese University Beirut (2006), Master of Science in Materials Science and Engineering at INSA Lyon (2007), PhD in materials engineering at INSA Lyon (Laboratory MATEIS) and University Claude Bernard Lyon 1 UCBL - LPMCN Laboratory (2011), Lecturer at Claude Bernard University (2011) and the University of South Brittany, Lorient (2012).
Ali MAKKE carries out his research at the Charles Delaunay Institute (LASMIS Laboratory) at the University of Technology of Troyes.

Research topics: Simulation of the mechanical behavior of materials at the molecular level. Study of the mechanical behavior of agro materials.

Keywords: simulation, finite element, molecular dynamics, polymers, copolymers blocks, initiation of damage (cracking, nucleation of cavities ...), parallel supercomputing.

Yazid MadiYazid MADI : Ph.D. in Mechanical Engineering, Civil Engineer, “Agrégation” in Civil Engineering, Master Structure-Materials Reliability. Course: PhD student at CEA / Saclay, France (1998-2001), Researcher at Centre des Matériaux, Mines ParisTech (2001-2002), High School Teacher (2003-2008), Assistant Professor at EPF (since 2008).
Yazid MADI carries out his research since 2008 in partnership with the Centre for Materials Pierre-Marie Fourt (Mines ParisTech)

Research topics: Behavior, damage and fracture of metallic alloys. All activities, based on experimental and numerical approach, have to respond to industrial concerns in the areas of energy and transport. The main topics covered are:

  • Fatigue: Influence of residual stress on crack propagation in alloys, low cycle fatigue of welded assemblies at high temperature taking into account its bi-material behavior, multiaxial fatigue of a steel pipeline.
  • Ductile tear: study of a bi-material welded assembly (predicting the path of cracking) on the tensile strength, study of the anisotropic behavior, study of plastic deformation due to pre-process shaping of plates, mixed mode analysis by DIC (Digital Image Correlation) imaging techniques, plastic confinement effect of a steel pipeline, propagation of a crack in the thickness of a thin-walled aluminum alloy.

Keywords: metal alloys, damage, failure.

Joseph Marae DjoudaJoseph MARAE DJOUDA: Graduate student of University of Orléans in Advanced Materials and Technologies in 2012, Joseph continued in thesis at University of Technology of Troyes at the same year. He is Ph. D in Materials Mechanics Optics and Nanotechnologies in 2016. He conducted is thesis at the interface between Optics (Laboratory of Nanotechnology, Instrumentation and Optics, LNIO) and Mechanics (Laboratory of Mechanical Systems and Concurrent Engineering, LASMIS). The aim was to design a sensor for strain measurements at the nanoscale based in optical coupling of gold nanoparticles.  

Research topics:
Mechanics of materials (in association with the Materials Center Pierre-Marie Fourt of Mines PARISTECH School). This mainly involves the delivery of studies in solid materials mechanics for industrial companies such as ENGIE, TOTAL and SAIPEM. The behavior and mechanical damage of the pipeline steels are investigated both experimentally and numerically. Methods for assessment of strains in pipeline defects are also proposed.
Keywords: mechanical behavior of steel, damage, ductile failure, plasticity, finite element analysis, materials characterization.

Study of the plasmon response of regular arrays of plasmon sub-entities
Joseph also develops research on plasmonic engineering based on coupling of 2D regular arrays of gold nanoparticles for sensor device design. Combining these plasmonic couplings with flexible substrates, the possibility to build sensors for mechanical applications like nanometric strain sensor is studied. This research is develop in an international environment in collaborations with colleagues of the Department of Physics of University of Calabria and South University of Science and Technology (SUSTech), University of Lille and University of Technology of Troyes.
Keywords: plasmon, optical coupling, regular arrays of plasmon sub-entities, sensors, nanofabrication, flexible substrates.

Naman RechoNaman RECHO : Naman Recho is responsible for the MECHANICS axis. Doctor Engineer (1980), PhD in  Physical Sciences (1987) from the University Pierre et Marie Curie Paris 6. Full Professor (1988). Since 1993, Professor UBP (Université Blaise Pascal) at University of Clermont-II and at Pascal Institute. Founder (1986) of Mechanics of Materials and Structures option - MMS EPF- at EPF Sceaux. Research Advisor at EPF since 2007.

Research topics: Linear and non-linear mechanics of fracture, fatigue of welded joints and probabilistic analysis, breakage problems from geometric and physical singularities, criteria bifurcation of cracks in structural components subjected to fatigue

Former members

Laurent Chin FooLaurent CHIN FOO : EPF-HEI PhD student (HEI-EPF PhD scholarship).

Subject: "mechanical and failure singularities - experimental analysis, numerical modeling and model validation.".

Supervision : Naman RECHO (EPF), Jean-Marie NIANGA (HEI).


Duy Cuong NguyenDuy Cuong NGUYEN : EPF-UTT PhD student (Regional CG 10 PhD scholarship).

Subject: "Characterization of fiber/matrix interface. Application to polypropylene/hemp composite".

Supervision : Ali MAKKE (EPF), Guillaume Montay (UTT).


Clement SoretClement SORET : Mines ParisTech - EPF PhD student (TOTAL CIFRE PhD scholarship).

Subject: "Strain based design of pipelines".

Supervision : Yazid MADI (EPF), Jacques Besson (Mines-ParisTech)



With its level of excellence, the MECHANICS axis is spreading expertise and conducts research partnerships with several private partners such as TOTAL, BUREAU VERITAS, GDF SUEZ, Nippon Steel, Cryospace.

At the international level, the MECHANICS axis also collaborates with the Department of Physics of the University of Calabria and the South University of Science and Technology (SUSTech), and the University of Lille (plasmonic engineering), and With the British Columbia Institute of Technology (BCIT, additive manufacturing).

The ERMESS axis is involved in the cluster MATERALIA, and also collaborates with universities to calls for projects (ANR, region ...).


In order to develop innovative tools mechanical engineering, the MECHANICS axis relies on the following tools:

  • An EPF R&D laboratory dedicated to additive manufacturing: professional printer in high definition and color, stratoconception , stratoconception, 3D scanner, thermal cameras, thermoforming unit.
  • CAD Modeling (CATIA);
  • Modeling and simulation of structures and processes (ABAQUS, ZEBULON, CAST3M).

Laboratoire EPF Troyes

In partnership with the Charles Delaunay Institute and the Center for Materials Characterization platforms:

  • Fatigue, tension-compression and dimensional inspection equipments;
  • Equipments for characterization of residual stresses (method of incremental hole, optical methods, X-ray diffraction);
  • Microstructural characterization of materials (SEM, TEM, EBSD, etc.);


1. Books

N.RECHO, J.BARES, B.RICHARD, "Méthode de calcul par éléments finis : Principe, matrices élémentaires, assemblage. Cours et exercices corrigés" Editions : Ellipses, Collection Technosup (192 pages). ISBN :978-2-340-00400-9. Date de publication: 17/03/2015
N.RECHO, "Fracture Mechanics and Crack growth", Editions: John WILEY (512 pages). ISBN: 978-1-84821-306-7, Mars 2012.
N.RECHO, "Hamiltonian Formalisms Applied to Continuum Mechanics: Potential Use for Fracture Mechanics", Chapitre du livre: Materials with Complex Behaviour II, Editions Springer –Verlag :Advanced Structured Materials, 2012, Volume 16, Part 1, pp 19-35, DOI: 10.1007/ISBN 978-3-642-22700-4_2, 2012.
N.RECHO,  "Mécanique de propagation et bifurcation des fissures", Editions HERMES-Sciences (288 pages) © LAVOISIER, ISBN 978-2-7462-3805-3, 2012.
N.RECHO,  "Mécanique de la Rupture par fissuration", aspects théorique, conceptuel et numérique, Editions HERMES-Sciences. (290 pages)© LAVOISIER, ISBN 978-2-7462-3118-4,2012.

2. International peer reviewed journals 

A. MAKKE, N. RECHO, " Comparison between Local and Global Crack Criteria of Crack Initiation Under Mixed Mode". Revue: Procedia Materials Science, Volume 3, 2014, Pages 90-96
2. N. RECHO, L. CHIN FOO, M. FARALDI, T. LASSEN, "Fatigue Design of Cruciform Joints including V-notch Effect at the Weld Toe". Revue: Procedia Materials Science, Volume 3, 2014, Pages 97-103
3. J.M. NIANGA, N. RECHO, "Hamiltonian Approach to Piezoelectric Fracture". Revue: Procedia Materials Science, Volume 3, 2014, Pages 318 324.
4. C.Z.CHENG, Z.HAN, S.YAO, Z.R. NIU, N. RECHO. “Analysis of heat flux singularity at 2D notch tip by singularity analysis method combined with boundary element technique”. Revue: Engineering Analysis with Boundary Elements. Volume 46, 2014, Pages 1-9
5. C.Z.CHENG, D.P. WANG, Z.R. NIU, N. RECHO,  “Singularity analysis near the vertex of the V-notch in Reissner’s plate by coupling the asymptotic expansion technique with the interpolate matrix method” Revue: Fatigue and Fracture of Engineering Materials and Structures (FFEMS). Wiley Publishing Ltd. Article first published online : 14 JUL 2014, DOI: 10.1111/ffe.12230

6. N. RECHO, "Fracture Mechanics". Journal: "Kirk-Othmer Encyclopedia". © 2013 by  John Wiley  and Sons, Inc. DOI: 10.1002/0471238961.0618010303181521.a01.pub2.  Article Online: January 18, 2013
7. C.Z.CHENG, Z.R. NIU, N. RECHO, “Analysis of the stress singularity for a bi-material V-notch by the boundary element method”. Revue: "Journal of Applied Mathematical Modelling". Volume 37, Issue 22, 15 November 2013, Pages 9398-9408
8. C.Z.CHENG, Z.R. NIU, N. RECHO, H. ZHOU,  "Analyze the role of the non-singular stress in brittle fracture by BEM", Fatigue and Fracture of Engineering Materials and Structures. (FFEMS) Wiley Publishing Ltd. Volume 36, Issue 5, May 2013, Pages: 416–426.
9.  C.Z.CHENG, N. RECHO, Z.R. NIU, "Influence of the non-singular stress on the crack extension and fatigue life", Nuclear Engineering and Design 248 (2012) pages 293–300
10. C.Z.CHENG, Z.R. NIU, N. RECHO, "Effect of non-singular stress on the brittle fracture of V-notched structure", International Journal of Fracture. Volume: 174   Issue: 2   Pages: 127-138   DOI: 10.1007/s10704-012-9680-8   Published: April 2012
11. Y. SHINOHARA, J. BESSON, Y. MADI, “Anisotropic Damage Behavior in High-Strength Line Pipe Steels”, International Journal of Offshore and Polar Engineering (ISSN 1053-5381), Vol. 22, No. 1, March 2012, pp. 83–89.
12. Chen, J., Madi, Y., Morgeneyer, T., Besson J. «Plastic flow and ductile rupture of a 2198 Al–Cu–Li aluminum alloy» Computational Materials Science, Volume 50, Issue 4, February 2011, Pages 1365-1371.
13. Shinohara, Y., Besson J., Madi, Y. «A combined phenomenological model for representation of anisotropic hardening behavior in high strength steel line pipes.» European Journal of Mechanics-A/Solids, Volume 29, Issue 6, November-December 2010, Pages 917-927.

3. International peer reviewed conferences 

1. T. Lassen, N. Recho, « Risk based inspection planning OF Fatigue cracks in offshore steel structures ». 34nd International Conference on Ocean Offshore and Arctic Engineering. OMAE 2015. May 31 - June 06, 2015, Saint John, Canada 
2. N. Recho , L. Chin Foo,  M. Faraldi, " Fatigue life prediction of welded joints as function of their singularity degree using energy release rate". 2nd International Symposium on Fatigue Design and Material Defects (FDMD II) 11, 13 juin 2014 Paris France.
3. A.GROUS, T.LASSEN, N.RECHO, " Estimation of the uncertainties on the fatigue reliability of a welded assembly
based on Power-law accelerated Birnbaum-Saunders life models ". Icossar - 2013 -11th International Conference on Structural Safety & Reliability June 16-20, 2013. Columbia University New York, NY
4. G.COUSSAN, N. RECHO, J.M.NIANGA, " Reliable Fatigue Design of Welded Joints following the Eurocode-3 -Conceptual Analysis and Possible Improvements.", , 8th ESIS TC2 Conference.  Mansfield College, Oxford 2nd and 3rd April 2012.
5. Burlot P., Chen, J., Madi, Y., Morgeneyer, T. « Anisotropic Plastic Behaviour of two 2198 Aluminum-Lithium Alloys» European Conference on Aluminium Alloys - ECAA. Bremen, October2011.
6. Madi, Y., Besson J., Tankoua, F., Chen, J., Recho, N. « Mixed-mode ductile fracture of an anisotropic 2024 Al-Cu Alloy.» ECF 18. Dresden, August 2010.
7. Besson J., Shinohara, Y., Morgeneyer, T., Madi, Y. « Ductile rupture of prestained X100 pipeline steel sheets.» ECF 18. Dresden, August 2010.
8. Shinohara, Y., Besson J., Madi, Y., « Anisotropic Damage Behavior in High Strength Steel Line Pipes». Bejing, June 2010.
9. Madi, Y., Chen, J., Morgeneyer, T., Besson J. «Modeling of plastic flow and ductile rupture of a 2198 Al-Li alloy for aeronautic applications.» IWCMM’19. Constana, 2009.

4. Conferences - Seminars - Courses

1. « Besoins et enjeux de la participation publique dans les démarches d’écologie industrielle et territoriale(DEIT) » Colloque COLEIT – Octobre 2014 – UTT - Julien Gardan (Pôle ERMESS, EPF), Emmanuelle Lorenzi (UMR 8185 ENEC Paris IV Sorbonne, URCA),Abdelatif Merabtine (ICD-CREIDD, UMR CNRS 6281, UTT, EPF)"
2. Yazid Madi Conférence de Joseph Marae ANM2014 à Aveiro - Portugal - 2-4 July 2014, 2 présentations orales : Organization of nanoparticles via copolymers templatesNanogauges gratings for strain characterization
3. Yazid Madi Conference ECF20 Trondheim Norvège, 1 présentation orale : Effect on constraint on anisotropic ductile fracture in a grade X63 line pipe steel
4.  Yazid Madi Poster Conference ECRS-9 Troyes : Effect of Residual Stresses on brittle fracture

5. N. RECHO, Cours d’excellence (CORSO DI ECCELLENZA) intitulé: “Advances in fracture mechanics for mechanical design activity”, 23 au 25 Octobre 2012. Cours destiné aux étudiants en Doctorat dans le cadre de l’école doctorale à Polytechnique de Turin en Italie.