Numerical analysis of lattice core sandwich plates by two-step finite element method

In present study, a numerical analysis of a sandwich structure with a lattice core consisting of two outer layers of sheets and an internal lattice core was undertaken. A two-step finite element method was applied to explore their mechanical behavior. The investigation primarily focused on evaluating the natural frequencies, critical buckling load, and maximum deformations of these plates. In first step, the finite element method was used to meticulously calculate the extensional stiffness, bending-extensional coupling stiffness, and bending stiffness matrices for a unit cell of lattice core. A cell was modeled in SAP2000 initially and then the entire structure was expanded. After that, in second step, the response of lattice structures was conveniently calculated by employing the stiffness matrices that were calculated in the first step. The obtained results were thoroughly compared with existing literature, ensuring the precision and reliability of the findings. These findings offer valuable insights for the design and optimization of sandwich structures with lattice core configurations across various engineering applications.