Prof. Philippe Viot

My research concerns the response of materials and structures under dynamic loadings (crash, impact, shocks). The applications of this research are the safety of goods and people, safety in transport, improving the performance of sports equipment…The behavior of materials such as architectured materials, composites, cellular wood, or foams, under high strain rates or the response of structures to dynamic stresses are considered.

The scientific approach is based on three pillars.

First, the macroscopic measurement and the analysis of the behaviour of these heterogeneous materials are carried out in considering the influence of the strain rate. Experimental apparatuses are then developed to estimate the stress-strain behaviour of these materials over a wide range of strain rates.

Secondly, the morphology of the materials is studied, and the damage localization is evaluated. The influence of the structure of the cellular material and the flow of gases in the structure are determined. The effects of local deformation are highlighted post-mortem. These experiments are complemented by analyses of deformation fields (DIC) on the surface of the sample or by microtomographic analyses.

Finally, these mechanical approach at the different scales of the material structure make it possible to model and simulate the response of the material by taking into account its specific multi-scale structure. Finite Element Model can be used with industrial FE Software but original way of modelling by Discrete Elements Method (DEM) are also developed with colleagues to reproduce local damage and failure.