Through-Thickness Load Transfer in Adhesively Bonded Composite Joints

Novel full-field measurement techniques are used to evaluate the complex stress and strain distributions in adhesively bonded composite joints using Thermoelastic stress analysis (TSA) and Digital image correlation (DIC). Magnifying optics are used to provide high resolution data with high measurement precision. Small, but critical, localised stress and strain concentrations are observed at this magnification, which contribute significantly to the initiation of damage and joint failure. The experimental stress and strain data is manipulated to give the same output for the purpose of comparison. A reasonable agreement between the two independent measurement techniques is achieved. The approach provides the basis for an accurate experimental validation methodology for the development of efficient numerical modelling methods.