Full 3D Measurement of Strain Field by Scattered Light for Analysis of Structures

The studies of structures with complex geometry or non-plane loading impose generally taking into account the mechanical volume effects. Mechanical data at the core of materials can be obtained by using special devices, generally from X-ray tomography. In this paper, we present an original volume investigation technique for transparent materials. This technique, easier to implement, does not require any complex device. It is based on scattered light by randomly distributed marks and provides three-dimensional images allowing the use of correlation technique, extended to three dimensions. The accuracy of measurement is evaluated for an imposed rigid body translation and a mechanical homogeneous loading in small and large strains. In conclusion, an example of application is presented concerning a local mechanical loading of compression in which we make a comparison with a finite element simulation.