Abstract: To investigate the flatwise tensile strength of the plain weave panels honeycomb sandwich structure, ABAQUS was used to create a detailed model of the sandwich structure based on the progressive damage failure analysis methodology. The cohesion model was selected to simulate the adhesive layer between the faceplate and the honeycomb core. FORTRAN language was applied to write USDFLD subroutines describing failure and degradation criteria, which predict the flatwise tensile properties of the sandwich structure. The results show that the predicted flatwise tensile strength and failure mode are consistent with the test results, checking whether the model is correct. There is no damage between the layers of the faceplate and the adhesive layer between the faceplate-core. The honeycomb damage is mainly caused by longitudinal damage to the honeycomb wall. Damage occurs first in the middle of the core wall, then the damage spreads to both sides. Finally, the middle part of the whole honeycomb core cracks and the structure fails. The peel strengths of the layers of the faceplate and the adhesive layer between the faceplate-core are higher than the tensile strength in the longitudinal direction of the core. The deformation of the entire sandwich structure is dominated by the deformation in the longitudinal direction of the core.

Key words: honeycomb sandwich structure, plain weave, progressive damage analysis, flatwise tensile properties, failure mode