Identification of adhesive properties in GLARE assemblies using digital image correlation

An experimental-numerical methodology is introduced to identify the parameters of a cohesive law of an adhesive layer within a joined assembly on the basis of kinematic data provided by digital image correlation. Non-conventional experiments on joined samples were designed to generate within the assembly and the adhesive film complex strain and stress states close to those expected in-service and up to complete debonding. The modeling is developed with reference to the observed sub-domain in which the experimental boundary conditions are prescribed. The nonlinear behavior of the adhesive layer is described as a finite-thickness interface endowed with a mixed-mode cohesive law whose parameters are identified so as to match at best the measured displacement field.