Numerical modelling of partially potted inserts in honeycomb sandwich panels under pull-out loading

Sandwich panel inserts are prone to pull-out loading, while predicting the pull-out strength is challenging due to the multitude of damage mechanisms involved. The present paper describes the implementation of two state-of-the art non-linear finite element models for predicting the pull-out strength. The two models include a 3D-continuum model where the core was modelled using 8-node brick elements with a homogenized material model and a detailed meso scale model with accurate honeycomb cell representation using 4-node shell elements. The simulation results are benchmarked against experimental data of the reference configuration. Both models enable to predict the strength accurately, while the 3D-continuum model can be considered favourable for most applications due to the reduced computational effort.