Laurent Maheo
Chercheur sous contrat (Post-Doc), Arts et Metiers Bordeaux - I2M-DuMAS
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- Updated : 02/04/2011 -
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Welcome to my Viadeo home page.
A few words to introduce myself.
I graduated from the University of South-Brittany in France and my PhD thesis in Mechanical Engineering deals with the damping efficiency of the explicit time algorithms used in the FEM simulations of dynamics.
Throughout the 2002-2006 period, I studied these damping methods theoretically and I developed a new algorithm which enhances the damping efficiency of the explicit and dissipative TW algorithm. Throughout the 2006-2009 period, I kept working on these damping methods. I therefore studied the propagation of 1-D and 3-D elastic waves in order to compare the damping methods to each other. Today, I am writing a new article on the use of the TW algorithm to the case of reversible (hyperelastic) and non reversible (plastic and hyperelastic-hysteresis) behaviors in finite transformations.
My master thesis deals with the influence of tensile pre-stress in shipbuilding steel sheets subjected to transverse low velocity impact, as frigates collisions. FEM simulations and experiments show losses of contact between the projectile and the steel sheet during the impact. I also studied the wave propagation in the steel sheet and the influence of the boundary conditions. This research work has been realized thanks to the original impact device
developed by the limatb research laboratory in Lorient, France. During, the first year of my PhD thesis, I co-developed with the research team a new instrumented projectile for load measurements during impact. This projectile which is based on the Tanimura study gives the contact force between the sheet and the projectile during the impact.
A description of my research works can be downloaded from the website:
http://web.univ-ubs.fr/lg2m/~lmaheo/
I have worked seven years (2002-2009) as a lecturer in the French Military academy of Saint-Cyr Coëtquidan. I tought more than 1200 hours to the French Cadets about the solid mechanics, the finite element method and projects about military use.
Today, I am researcher at the Lamefip, Arts et Métiers in Bordeaux. I work in the LISTRAC ANR project which deals with the multi-scale modelization of the foam materials (polypropylène, polystyrène ...). This research area is quite exciting and it's very fun for me.
If you want to know me better, you may send me an e-mail to laurentmaheo[at]hotmail.com and maybe we may have a lunch to talk about everything in an informal situation.
See you.
31 contacts*******************************
Researcher (18 months)
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Numerical simulations with the Finite Element Method (LS-Dyna) and the Discrete Element Method (universitary software).
To be continued with results ...
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International article:
- Viot, P., Mahéo, L., Mercier, A.,"Behaviour of polymeric multiscale foam under dynamic loading - Study of the influence of the density and the walls of beads". Int J Research Rev Appl Sc (accepted).
2002 - 2009*******************************
Researcher (7 years)
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PhD thesis: Dissipative explicit time integration schemes in FEM dynamics.
This phd-thesis deals with several time integration algorithms which are used in dynamics computation. The study focuses on their vibration damping properties in order to dissipate spurious oscillations generated by the use of space and time discretizations. The main items are:
- Numerical simulation of wave propagation.
- Theoretical and numerical studies.
- Improvement of the explicite TW scheme: automatic design of the damping parameter.
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PhD Thesis:
http://web.univ-ubs.fr/lg2m/~lmaheo/These_Maheo... (in French)
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3 international articles:
- Mahéo, L., Grolleau ,V., Rio, G. Damping efficiency of the Tchamwa-Wielgosz explicit dissipative scheme under instantaneous loading conditions. C.R. Mécanique, 337(11-12), 2009, 722–732.
http://dx.doi.org/10.1016/j.crme.2009.10.005
- Mahéo, L., Rio, G., Grolleau, V. On the use of some numerical damping methods of spurious oscillations in the case of elastic wave propagation. Mech Research Com, 38, 2011, 81–88.
http://dx.doi.org/10.1016/j.mechrescom.2011.01....
- Mahéo, L., Grolleau, V., Rio, G. Numerical damping of spurious oscillations: a comparison between the Bulk-Viscosity method and the Tchamwa-Wielgosz dissipative explicit scheme. Comput Mech, 19 pages (re-submitted february, 4th 2011).
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Lecturer (7 years)
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More than 1200 hours of teaching to the French Cadets about the Solid Mechanics, the Continuum Mechanics, the Finite Element Method and projects about military use.
2002 - 2002*******************************
Researcher (5 months)
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Master thesis: Naval steel sheets subjected to low velocity impacts.
During frigates' construction, sheets' adjustment is not done precisely. On sheets of several square meters, adjustment variations can reach several centimetres. To assemble these sheets, technicians must join them (creation of stress in the sheets) to be able to weld them. That's why it appears pre stress in the majority of ship's sheets. The main items are:
- Design of the tensile pre-stress device with Catia V5 software.
- Experiments with the LimatB impact device.
- FEM simulation of the impact test with LS DYNA.
- Study of the influence of the tensile pre-stress in E355-FP steel sheets.
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Master Thesis:
http://web.univ-ubs.fr/lg2m/~lmaheo/Master_Mahe... (in French)
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International article:
- Galpin, B., Grolleau, V., Rio, G., Umiastowski, S., Mahéo., L. Design and application of an instrumented projectile for load measurements during impact". Int J Crashworthiness 13(2), 2008, 139–148.
http://www.informaworld.com/10.1080/13588260701...
Engineer Trainee, ArcelorMittal R&D - Department of Steel Solution for Automotive - Montataire ? France
2001 - 2001*******************************
Engineer (6 months)
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Work placement: Manufacturing of a tripode node by hydroforming process.
- Design and manufacturing of a space frame compnent of a bus: a tripod node.
- FEM simulation of the process with Pam-Stamp.
- Design of the hydroforming process parameters.
- Conception of the hydroforming mold.
- Experiments with the Arcelor hydroforming device.
- Prototype manufacturing, and geometrical optimisation.
Technician Trainee, ArcelorMittal - Department of Metallurgy and Quality - St Chély d'Apcher - France
2000 - 2000*******************************
Technician (3 months)
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Work placement: Study of magnetic anistropy observed in steel sheets used for electric motors.
- Induction and magnetic dissipation measurements.
- Maintenance of the annealing furnaces: thermocouples replacement.
- Modification of a software about the measurement of sheet thickness.