Determining elastic constants of materials with interferometric techniques

Abstract

The article describes a method that combines finite element analysis and genetic algorithms in order to determine the elastic properties of materials from the full-field measurement of the surface displacements of plates under flexural loads. An optimizing process updates the elastic constants in a numerical model until the calculated displacements fit the experimental data. The unknown parameters are identified simultaneously by a single test and without damaging the structure. An original method is also proposed for optimizing the loading and constraining conditions of the specimen with a view to obtaining faster and more stable solutions. The procedures were applied to a steel specimen whose displacement field was detected by speckle interferometry.