Finite element modeling of the bending and vibration behavior of three-layer composite plates with a crack in the core layer

For multi-layered composite plates made up of different types of material components, each layer commonly has a different reinforcement angle (angle-ply). In the working process, cracking defects may appear, which also due to there being numerous layers, cracks can appear only in a certain inner layer without the surface layers being cracked. This necessitates considerable research. Therefore, this study uses the third-order shear deformation theory in conjunction with the phase-field theory to model the free vibration response and static bending of laminated composite plates with just a core layer fracture. Additionally, this is the first investigation to integrate the finite element method with phase-field theory in order to model the appearance of a fracture in a portion of the plate thickness. The phase-field variable is utilized to convert the crack to a continuous domain, which simplifies calculation; this is also a property that other computational theories lack. The results of the calculations show some surprising things that have never been seen before. For example, the length of the crack changes, but the natural frequency and maximum deflection of the plate don't change much, which makes it hard to find this kind of fault. © 2022 Elsevier Ltd