Dynamic strain & stresses for enhanced reliability: from full field optical measurements to simulations

The development of full field measurement technologies can lead nowadays, thanks to the accuracy and consistency of the data fields, to a reliable estimation of dynamic surface strains. Beside the relevant role of advanced benchmarks for the optimisation of numerical models, advanced finite element formulation and fatigue analysis, the experimentally obtained strain maps can be used directly for straightforward analyses and simulations of component behaviour in challenging dynamic events. The impedance experimental model for refined dynamic strains can evaluate, by means of constitutive relations and no assumptions on critical boundary conditions nor on damping, the response stress distribution and, with the knowledge of excitation dynamic signature, the complete behaviour of component surface in real-life dynamic events. There results an accurate map of dynamic fatigue that can be exploited in the design process as well as in the manufacturing and diagnostic activities for critical components, to provide an overall enhanced reliability. By approaching the task with the aid of superior quality dynamic displacement, this work shows the evaluated dynamic strain & stress model from Hi-Speed DIC time domain full field measurement technology. A thin plate is measured as light-weight structure with broad band dynamics and high modal density in a unique comparative set-up. The impedance experimental model of the dynamic strain & stresses is then used with different excitations to validate the whole approach, which is then discussed in detail.