A methodology to predict the static strength of bolted joints in Fibre Metal Laminates

Joining structural components in aircraft is generally performed through mechanical fastening. The interaction of bearing and bypass stresses in composite bolted joints causes a reduction in the static strength of the joint. The bearing-bypass diagram determines the bearing and net-section failure modes. This thesis work aims to provide a design methodology to develop the so-called bearing bypass diagram to predict the static strength of bolted joints in Fibre Metal Laminates. The methodology proposed is based on first principles and can be applied to generic FMLs and different joint configurations. A close match is observed with the analytical solution and existing experimental test data for GLARE-2A and GLARE-3. Apart from bearing and net-section failure modes, GLARE laminates were subjected to fastener pull-through failure. Considering the effect of secondary bending, a preliminary methodology was developed to determine the FPT failure in GLARE. Comparison of the analytical solution with the existing experimental data on GLARE revealed a close match in the trend.
Aerospace Engineering