SIMULTANEOUS ASSESSMENTOF COHESIVE PARAMETERS AND BOUNDARY CONDITIONS,ON THE BASIS OF KINEMATIC MEASUREMENTSAT THE MICROSCALE

This paper represents a contribution to the study of identification procedures resting on kinematic measurements provided by Digital Image Correlation (DIC). Reference is made to non-conventional laboratory tests on adhesively bonded assemblies for aerospace applications, in which the mechanical properties of the adhesive joint are regarded as unknowns to be estimated. Full-field measurements allow one to monitor and model exclusively a small sub-domain (Region-Of-Interest, ROI), by prescribing kinematic conditions along its boundary. As a drawback of this local approach, worsened by the slender geometry and the nonlinear material behavior, noise on data from the outer boundary propagate throughout the sub-domain, influencing the final estimates and generating hardly legible strain and stress fields. As a novelty, here smoothing of boundary data and identification of mechanical parameters, so far performed in a sequence, are tackled simultaneously in a coupled framework. An augmented parameter space is considered for identification, including both the (cohesive) mechanical parameter of the interface and the “actual“ boundary conditions.