Thermo-Mechanical Analysis of Laminated and Sandwich Plates—Bending and Buckling Behavior

Abstract

This paper presents a comprehensive thermo-mechanical analysis of laminated composite sandwich plates, focusing on bending deformations and buckling stability under combined thermal and mechanical loading. A First-Order Shear Deformation Theory (FSDT)-based formulation is employed, and a finite element model is developed in ABAQUS to simulate plate response. A symmetric sandwich plate with carbon/epoxy face sheets and a lightweight core is analyzed under a uniform transverse pressure and a through-thickness temperature gradient. Results show that thermal effects substantially increase the bending deflection (over 100% rise for a 100°C gradient) and alter stress distributions, with face sheets carrying most of the load while the core bears minimal stress. Parametric studies indicate that a higher temperature gradient notably reduces the plate’s effective bending stiffness (by ~18%) and consequently lowers the critical buckling load and natural frequencies. The numerical predictions are validated against an analytical FSDT solution, showing close agreement (<5% difference in deflection). These findings highlight the importance of including thermal loads in the design of composite sandwich structures and demonstrate the accuracy of the FSDT-based finite element approach for predicting their structural behavior.