Extensometric and Thermo-Elasticimetric Measurements to Characterize the Damage Evolution in Adhesively Bonded Joints: Application for the Adhesively Bonded Double Scarf Joint

In this article, two nondestructive experimental methods are compared in order to evaluate the influence of a singularity, created by geometry, on the damage evolution in the adhesively bonded joints. The first experimental method uses the "back face technique" to measure the disturbances of the strain fields induced by the cracks. The second experimental method uses an infrared focal plane array camera to measure the thermo-elastic field in the geometrical singularity. First of all, both methods are carried out independently: the analysis of the stress/strain and the thermo-graphic analysis. Then, these two methods enabled us to generate a database, the use of which improves the diagnosis of the damage state of the adhesively bonded joints.